FN Thomson Reuters Web of Science™ VR 1.0 PT J AU GIPSON, RD HUBERT, WA AF GIPSON, RD HUBERT, WA TI FACTORS INFLUENCING THE BODY CONDITION OF RAINBOW-TROUT IN SMALL WYOMING RESERVOIRS SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article ID MORPHOEDAPHIC INDEX AB Possible relations between the body condition of rainbow trout (Oncorhynchus mykiss) and the density of salmonid fishes, the abundance of non-salmonid fishes, and two measures of biological productivity-total dissolved solids and elevation above mean sea level-were assessed for 13 small (< 170 surface hectares) reservoirs in Wyoming. The mean condition of rainbow trout was positively related to total dissolved solids and negatively related to the abundance of non-salmonid fishes. RP GIPSON, RD (reprint author), UNIV WYOMING,US FISH & WILDLIFE SERV,WYOMING COOPERAT FISH & WILDLIFE RES UNIT,LARAMIE,WY 82071, USA. NR 22 TC 7 Z9 8 U1 0 U2 1 PU OIKOS PUBL INC PI LA CROSSE PA PO BOX 2558, LA CROSSE, WI 54601 SN 0270-5060 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD SEP PY 1991 VL 6 IS 3 BP 327 EP 334 DI 10.1080/02705060.1991.9665310 PG 8 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA GN009 UT WOS:A1991GN00900012 ER PT J AU JONES, DS MACFADDEN, BJ WEBB, SD MUELLER, PA HODELL, DA CRONIN, TM AF JONES, DS MACFADDEN, BJ WEBB, SD MUELLER, PA HODELL, DA CRONIN, TM TI INTEGRATED GEOCHRONOLOGY OF A CLASSIC PLIOCENE FOSSIL SITE IN FLORIDA - LINKING MARINE AND TERRESTRIAL BIOCHRONOLOGIES SO JOURNAL OF GEOLOGY LA English DT Article ID ATLANTIC COASTAL-PLAIN; STRATIGRAPHY; RATES; FAUNA AB One of the most spectacular fossil molluscan faunas known to paleontologists is exposed in a large shell pit near Sarasota, Florida, where on the order of 1,000 well-preserved, shallow marine species are found. Sandwiched between extensive shell beds is a unit containing a rich vertebrate fauna (ca. 100 species) with a distinctive mammalian component indicative of the late Blancan Land Mammal Age (2.5-2.0 Ma). In contrast, the surrounding shell beds have traditionally been assigned an older (early to mid-Pliocene) age based upon biocorrelation of the benthic invertebrate (molluscan) fauna. Precise dating is difficult, however, as preservation of planktonic micro- and nannofossils was not favored in the nearshore paleoenvironmental setting. In a multi-faceted approach, we integrated invertebrate biochronology (ostracodes), vertebrate biochronology (Land Mammal Age), paleomagnetism (a unique application in such coarse shell beds), and strontium isotope chronostratigraphy with existing age data from the literature in an attempt to resolve this chronologic dichotomy and link the marine and terrestrial records. All sites yielded reversed magnetic polarities. Based upon the vertebrate biochronology, as well as ostracode correlations and the Sr-87/Sr-86 ratios from each unit, we place the principal bone-bearing unit (Unit 4) and overlying beds within the lower portion of the Matuyama Chron (ca. 2.5-2.0 Ma). The underlying units (Units 5-10) are probably older, with a depositional age between 2.5 and 3.5 Ma. The lowermost unit (Unit 11) may be as old as early Pliocene. C1 UNIV FLORIDA,DEPT GEOL,GAINESVILLE,FL 32611. US GEOL SURVEY,RESTON,VA 22092. RP JONES, DS (reprint author), UNIV FLORIDA,FLORIDA MUSEUM NAT HIST,GAINESVILLE,FL 32611, USA. RI Mueller, Paul/B-3974-2013; OI Mueller, Paul/0000-0003-2608-193X NR 50 TC 34 Z9 35 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0022-1376 J9 J GEOL JI J. Geol. PD SEP PY 1991 VL 99 IS 5 BP 637 EP 648 PG 12 WC Geology SC Geology GA GF117 UT WOS:A1991GF11700001 ER PT J AU DONATO, MM AF DONATO, MM TI GEOCHEMICAL RECOGNITION OF A CAPTURED BACK-ARC BASIN METABASALTIC COMPLEX, SOUTHWESTERN OREGON SO JOURNAL OF GEOLOGY LA English DT Article ID KLAMATH MOUNTAINS; ISLAND-ARC; VOLCANIC-ROCKS; METAMORPHIC ROCKS; SPREADING CENTER; SCOTIA SEA; MAGMA TYPE; CALIFORNIA; PETROLOGY; DISCRIMINATION AB An extensive fault-bounded amphibolite terrane of Late Jurassic (145 +/- 2 Ma) metamorphic age occurring in the northeastern Klamath Mountains of southern Oregon has been recognized as the remnants of an ancient back-arc basin. In spite of thorough metamorphic recrystallization under amphibolite-facies conditions, the amphibolite locally displays relict igneous textures which suggest that the protoliths included basaltic dikes or sills, shallow diabase intrusions, and gabbros. The major- and minor-element chemistry of the amphibolite indicates that some alteration of original compositions has occurred. Nevertheless, certain elements (e.g. Zr, Ti, Y, Hf, P, Th, Ta, and the REE) were probably immobile and retain their original igneous abundances. Chondrite-normalized REE patterns are similar to those of mid-ocean ridge basalt (MORB): concave-downward and flat or slightly LREE-depleted, with abundances about six to 30 times chondritic values. Patterns are slightly LREE-enriched and HREE-depleted relative to average MORB. Most samples plot in or near MORB fields in tectonomagmatic discrimination diagrams, but relative enrichment in Th and the LREE suggest the involvement of subduction-related fluids in magma genesis. In this regard, the amphibolite is very similar to some back-arc basin basalts. The geochemical data, together with the present-day geologic context, indicate that the tectonic setting of eruption/intrusion was probably within a back-arc basin that existed inboard (east) of a pre-Nevadan volcanic arc. The basalt (now amphibolite) and the overlying sediments (now the May Creek Schist) were metamorphosed and deformed during accretion to North America during the Late Jurassic Nevadan orogeny. RP DONATO, MM (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 68 TC 8 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0022-1376 J9 J GEOL JI J. Geol. PD SEP PY 1991 VL 99 IS 5 BP 711 EP 728 PG 18 WC Geology SC Geology GA GF117 UT WOS:A1991GF11700006 ER PT J AU WANG, TC DUXBURY, TC SYNNOTT, SP EDWARDS, K AF WANG, TC DUXBURY, TC SYNNOTT, SP EDWARDS, K TI APPROACH FOR TARGETING LANDERS AND PENETRATORS USING ORBITAL OPTICAL NAVIGATION SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID CONTROL NETWORKS; PLANETS; SATELLITES; PHOBOS AB A new approach for targeting landers, rovers, and penetrators to specific points on the surfaces of planetary bodies using onboard, orbital optical navigation data is presented. Earth-based radiometric tracking of the orbiting spacecraft provides a very precise determination of the spacecraft orbit about the primary planetary body. Onboard optical navigation images are then used to relate the spacecraft orbit to the surface of the target body. This paper concentrates on the problem associated with using the onboard optical navigation data, which will have to estimate, in a near-real time orbit determination process, a large set of parameters including the spacecraft orbit and primary body gravity field, the rotational properties of the planetary body, the coordinates of surface features, and the camera pointing and orientation of each picture. A batch-sequential formulation of the standard least squares problem is used with the addition of backward smoothing. A square-root information filter is also used for numerical precision and stability and to minimize computer memory. To illustrate this approach, over 100 images of Phobos were processed to estimate about 2000 parameters including the camera pointing angles, the rotational properties of Phobos, and the locations of surface features. C1 US GEOL SURVEY,ASTROGEOL BRANCH,FLAGSTAFF,AZ 86001. CALTECH,JET PROP LAB,DIV EARTH & SPACE SCI,PASADENA,CA 91109. CALTECH,JET PROP LAB,NAVIGAT SYST SECT,OPT SYST ANAL GRP,PASADENA,CA 91109. RP WANG, TC (reprint author), CALTECH,JET PROP LAB,NAVIGAT SYST SECT,TECH STAFF,MAIL STOP 301-220G,4800 OAK GROVE DR,PASADENA,CA 91109, USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD SEP-OCT PY 1991 VL 14 IS 5 BP 973 EP 980 DI 10.2514/3.20738 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA GF532 UT WOS:A1991GF53200014 ER PT J AU DODD, CK AF DODD, CK TI DRIFT FENCE-ASSOCIATED SAMPLING BIAS OF AMPHIBIANS AT A FLORIDA SANDHILLS TEMPORARY POND SO JOURNAL OF HERPETOLOGY LA English DT Article ID NOTOPHTHALMUS-VIRIDESCENS RAFINESQUE; HUSTING DILEMMA; SALAMANDERS; PATTERNS; ECOLOGY; DENSITY AB Five years of field observations suggest that amphibians inhabiting a sandhills community are able to circumvent a drift fence-pitfall trap enclosure as they move toward and away from an ephemeral pond. Trespass rates varied depending on species and showed no tendency to increase or decrease as the study progressed. Laboratory trials confirmed that frogs easily crossed the fence by walking up the side or hopping over it. Frogs crossed the fence readily regardless of sex or whether the frog was an adult or juvenile. Although striped newts did not climb over the fence in the laboratory, they may use tunnels to go under fences under field conditions. Other species may burrow directly under the fence. A priori assumptions about a species' ability to climb a fence, or that trespass rates do not vary temporally or among sites, are unwarranted and may lead to misinterpretations of the results from studies using drift fences and pitfall traps. RP DODD, CK (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,412 NE 16TH AVE,ROOM 250,GAINESVILLE,FL 32601, USA. NR 22 TC 40 Z9 42 U1 0 U2 2 PU SOC STUD AMPHIBIANS REPTILES PI OXFORD PA DEPT OF ZOOLOGY MIAMI UNIV, OXFORD, OH 45056 SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD SEP PY 1991 VL 25 IS 3 BP 296 EP 301 DI 10.2307/1564587 PG 6 WC Zoology SC Zoology GA GD953 UT WOS:A1991GD95300006 ER PT J AU KJELSTROM, LC AF KJELSTROM, LC TI METHODS OF MEASURING PUMPAGE THROUGH CLOSED-CONDUIT IRRIGATION SYSTEMS SO JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING-ASCE LA English DT Article AB Methods of measuring volumes of water withdrawn from the Snake River and its tributaries and pumped through closed-conduit irrigation systems were needed for equitable management of and resolution of conflicts over water use. On the basis of evaluations and field tests by researchers from the University of Idaho, Water Resources Research Institute, Moscow, Idaho, an impeller meter was selected to monitor pumpage through closed-conduit systems. In 1988, impeller meters were installed at 20 pumping stations along the Snake River between the Upper Salmon Falls and C.J. Strike Dams. Impeller-derived pumpage data were adjusted if they differed substantially from ultrasonic flow-meter- or current-meter-derived values. Comparisons of pumpage data obtained by ultrasonic flow-meter and current-meter measurements indicated that the ultrasonic flow meter was a reliable means to check operation of impeller meters. The equipment generally performed satisfactorily, and reliable pumpage data could be obtained using impeller meters in closed-conduit irrigation systems. Many pumping stations that divert water from the Snake River for irrigation remain unmeasured; however, regression analyses indicate that total pumpage can be reasonably estimated on the basis of electrical power consumption data, an approximation of total head at a pumping station, and a derived coefficient. RP KJELSTROM, LC (reprint author), US GEOL SURVEY,DIV WATER RESOUR,230 COLLINS RD,BOISE,ID 83702, USA. NR 0 TC 2 Z9 2 U1 1 U2 1 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9437 J9 J IRRIG DRAIN E-ASCE JI J. Irrig. Drainage Eng-ASCE PD SEP-OCT PY 1991 VL 117 IS 5 BP 748 EP 757 DI 10.1061/(ASCE)0733-9437(1991)117:5(748) PG 10 WC Agricultural Engineering; Engineering, Civil; Water Resources SC Agriculture; Engineering; Water Resources GA GF906 UT WOS:A1991GF90600010 ER PT J AU CRONIN, TM AF CRONIN, TM TI LATE NEOGENE MARINE OSTRACODA FROM TJORNES, ICELAND SO JOURNAL OF PALEONTOLOGY LA English DT Article ID PLIOCENE; PLEISTOCENE; OCEAN AB On the western side of the Tjornes Peninsula in northern Iceland exposures of fossiliferous marine sediments, basalts, and glacial tills record the climatic history of this region of the North Atlantic Ocean. Seventy-five marine ostracode species were recovered from the Pliocene Tjornes sediments and Quaternary sediments known as the Breidavik beds. The ostracode assemblages contain many warm-water genera that do not inhabit Iceland today and indicate early to middle Pliocene (4.5-3.0 Ma) winter and summer bottom-water temperatures that averaged 5-6-degrees-C and 14-16-degrees-C, respectively (maximum 20-degrees-C in summer, rarely below 3-degrees-C in winter except during a brief cooling 3.5-3.2 Ma). An intensified North Atlantic Drift and a diminished or absent East Greenland Current account for warm-water oceanographic conditions at 66-degrees-N. Late Pliocene marine climates were cooler with winter and summer averages of about 9-degrees-C and 8-degrees-C. Early Pleistocene ostracode assemblages dated at 1.7-1.3 Ma contain extant arctic-subarctic species that indicate winter and summer temperatures of about -1.5-degrees-C and 4-5-degrees-C. New species Bensonocythere eirikssoni, Robertsonites williamsi, Hemicythere rekaensis, Thaerocythere mayburyae, Thaerocythere whatleyi, Leptocytheretjornesensis, Tetracytherura bardarsoni, and Cytheromorpha einarssoni are described. RP CRONIN, TM (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 68 TC 48 Z9 49 U1 0 U2 2 PU PALEONTOLOGICAL SOC INC PI ITHACA PA 1259 TRUMANSBURG ROAD, ITHACA, NY 14850 SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD SEP PY 1991 VL 65 IS 5 BP 767 EP 794 PG 28 WC Paleontology SC Paleontology GA GG380 UT WOS:A1991GG38000007 ER PT J AU TAYLOR, JF KENNEDY, DJ MILLER, JF REPETSKI, JE AF TAYLOR, JF KENNEDY, DJ MILLER, JF REPETSKI, JE TI UPPERMOST CAMBRIAN SLOPE DEPOSITS AT HIGHGATE-GORGE, VERMONT - A MINOR MISCORRELATION WITH MAJOR CONSEQUENCES FOR CONODONT-BASED AND TRILOBITE-BASED CHRONOCORRELATION SO JOURNAL OF PALEONTOLOGY LA English DT Article ID DUAL BIOSTRATIGRAPHY; PALEOSCENE =3; BIOFACIES; ZONES AB Uppermost Cambrian and lowest Ordovician slope deposits in Highgate Gorge, northwestern Vermont, yield a succession of conodont faunas (and a few associated trilobite species) similar to that observed in coeval North American carbonate-platform sequences. Decimeter-scale sampling of a 15-m-interval in two sections comprising thin-bedded limestone-shale rhythmites alternating with thick-bedded debris flow conglomerates yielded 60 trilobite specimens and more than 5,000 conodont elements from 48 productive horizons. The new biostratigraphic control does not support earlier claims that the lowest occurrence of Cordylodus proavus in the Gorge Formation and presumably in other slope sequences is significantly older than the base of the C. proavus Zone in platform deposits; rather, it demonstrates the isochronous persistence of this boundary across the North American (Laurentian) shelf margin into Iapetan slope deposits. The common occurrence of the deep, cool-water conodont Eoconodontus alisonae and the agnostoid trilobite Lotagnostus hedini in the Eoconodontus Zone at Highgate Gorge makes it possible to extend the correlation even farther from the Laurentian platform into uppermost Cambrian strata in Kazakhstan and China. This new information greatly strengthens arguments in favor of using this zonal boundary of defining the international boundary between the Cambrain and Ordovician Systems. In earlier studies of Highgate Gorge strata, composite treatment of biostratigraphic data from similar but non-correlative intervals (Zones 2 and 3) in two sections created an illusion of significant stratigraphic overlap of C. proavus with older faunas and direct association of some trilobite species for which overlap has never been established. Composite treatment of data from Zones 2 and 3 under designations such as "main zone" or "upper zone" should be discontinued and species that have been reported as occurring together in the "main zone" should not be assumed (on the basis of that association alone) to have come from the same stratigraphic level. C1 SW MISSOURI STATE UNIV,DEPT GEOSCI,SPRINGFIELD,MO 65804. US GEOL SURVEY,NATL CTR,RESTON,VA 22092. RP TAYLOR, JF (reprint author), INDIANA UNIV,DEPT GEOSCI,INDIANA,PA 15705, USA. NR 33 TC 7 Z9 7 U1 1 U2 1 PU PALEONTOLOGICAL SOC INC PI ITHACA PA 1259 TRUMANSBURG ROAD, ITHACA, NY 14850 SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD SEP PY 1991 VL 65 IS 5 BP 855 EP 863 PG 9 WC Paleontology SC Paleontology GA GG380 UT WOS:A1991GG38000012 ER PT J AU TRINCARDI, F FIELD, ME AF TRINCARDI, F FIELD, ME TI GEOMETRY, LATERAL VARIATION, AND PRESERVATION OF DOWNLAPPING REGRESSIVE SHELF DEPOSITS - EASTERN TYRRHENIAN SEA MARGIN, ITALY SO JOURNAL OF SEDIMENTARY PETROLOGY LA English DT Article ID DELTA; STRATIGRAPHY; SEQUENCES; EVOLUTION; BASIN AB The shelf of the eastern Tyrrhenian Sea margin changes substantially in width, shelf-break depth, and sea-floor steepness over relatively short distances, largely owing to pronounced lateral changes in subsurface geologic structure. Remnants of late Pleistocene prograded coastal deposits are locally preserved on the middle and outer parts of the shelf. We recognize two major controls on the distribution, lateral extent, thickness, and preservation potential of these prograded deposits. First, prograded (downlapping) deposits formed only where the physiographic shelf break was deeper than the lowstand shoreline, thus providing accommodation space for the lowstand deposits. Second, the proximity and relative size of sediment sources and the local coastal dispersal system apparently influenced the geometry of the deposit. Midshelf and shelf-margin bodies composed of seaward-steepening downlapping reflectors were deposited as thin to thick continuous prograding sheets over an irregular eroded shelf surface and onto the shelf edge during the latest fall and lowstand of sea level. Decreased sedimentation at the end of this lowstand resulted in net erosion. During sea-level rise, shoreface erosion created a major marine erosional (ravinement) surface landward of the 120-m isobath, and much of the downlapping deposits were removed. Preservation of these downlapping deposits is largely a function of their thickness. Thick continuous deposits are common on the shelf edge, whereas on the midshelf only thin remnants are preserved locally where depressions or morphologic steps were present in the shelf surface. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP TRINCARDI, F (reprint author), IST GEOL MARINA,VIA ZAMBONI 65,I-40127 BOLOGNA,ITALY. OI Trincardi, Fabio/0000-0002-8476-8804 NR 50 TC 64 Z9 64 U1 0 U2 0 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 SN 0022-4472 J9 J SEDIMENT PETROL PD SEP PY 1991 VL 61 IS 5 BP 775 EP 790 PG 16 WC Geology SC Geology GA GH561 UT WOS:A1991GH56100008 ER PT J AU KNEBEL, HJ RENDIGS, RR BOTHNER, MH AF KNEBEL, HJ RENDIGS, RR BOTHNER, MH TI MODERN SEDIMENTARY ENVIRONMENTS IN BOSTON HARBOR, MASSACHUSETTS SO JOURNAL OF SEDIMENTARY PETROLOGY LA English DT Article ID RHODE-ISLAND; INNER SHELF; BAY; ESTUARY AB Analyses of sidescan-sonar records supplemented by available bathymetric, sedimentary, subbottom, and bottom-current data reveal the distributions of the following three categories of sedimentary environments within the glaciated, topographically complex Boston Harbor estuary in Massachusetts. 1) Environments of erosion appear on the sonographs either as patterns with isolated strong reflections or as uniform patterns of strong reflectivity. These patterns define outcrops of bedrock or till and coarse lag deposits that are being scoured and winnowed by tidal- and wave-induced currents. Erosional areas are located primarily along mainland and insular shores, within large channels that have strong tidal currents, atop submerged ridges and knolls, and across much of the harbor entrance. 2) Environments of deposition are depicted on the sidescan-sonar records as smooth, featureless surfaces that have low to moderate reflectivity. Depositional environments are found predominantly over shallow subtidal flats and in broad bathymetric lows where tidal currents are weak. Sediments within depositional areas are organic-rich sandy and clayey silts that are accumulating at rates ranging from 0.01 to 0.11 g/cm2/yr or 4000 to 46,100 metric tons/yr. The cumulative mass of modern mud in harbor depocenters is 24.3 million metric tons. 3) Environments of sediment reworking constitute areas affected by a combination of erosional and depositional processes. They are characterized on the sonographs by mosaics of light and dark patches produced by relatively subtle and gradational changes in reflectivity. Reworked sediments have diverse grain sizes that overlap and are transitional between those of the other two sedimentary environments, and they are indicative of highly variable bottom currents. RP KNEBEL, HJ (reprint author), US GEOL SURVEY,WOODS HOLE,MA 02543, USA. NR 35 TC 22 Z9 22 U1 0 U2 2 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 SN 0022-4472 J9 J SEDIMENT PETROL PD SEP PY 1991 VL 61 IS 5 BP 791 EP 804 PG 14 WC Geology SC Geology GA GH561 UT WOS:A1991GH56100009 ER PT J AU SHINN, EA LIDZ, BH HOLMES, CW AF SHINN, EA LIDZ, BH HOLMES, CW TI HIGH-ENERGY CARBONATE-SAND ACCUMULATION, THE QUICKSANDS, SOUTHWEST FLORIDA KEYS - REPLY SO JOURNAL OF SEDIMENTARY PETROLOGY LA English DT Discussion C1 US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. RP SHINN, EA (reprint author), US GEOL SURVEY,600 4TH ST S,ST PETERSBURG,FL 33701, USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 SN 0022-4472 J9 J SEDIMENT PETROL PD SEP PY 1991 VL 61 IS 5 BP 861 EP 862 PG 2 WC Geology SC Geology GA GH561 UT WOS:A1991GH56100014 ER PT J AU HOWARD, PE DEIN, FJ LANGENBERG, JA FRISCHMEYER, KJ BRUNSON, DB AF HOWARD, PE DEIN, FJ LANGENBERG, JA FRISCHMEYER, KJ BRUNSON, DB TI SURGICAL REMOVAL OF A TRACHEAL FOREIGN-BODY FROM A WHOOPING-CRANE (GRUS-AMERICANA) SO JOURNAL OF ZOO AND WILDLIFE MEDICINE LA English DT Article DE WHOOPING CRANE; GRUS-AMERICANA; TRACHEAL FOREIGN BODY; TRACHEOTOMY; TILETAMINE ZOLAZEPAM AB The left wing of a whooping crane (Grus americana) was amputated for treatment of severe nonunion and malunion fractures of the radius and ulna. During the postoperative convalescent period, the bird aspirated a com kernel and subsequently suffered episodic bouts of dyspnea. The bird was anesthetized with tiletamine-zolazepam. Attempts to deliver the kernel through the glottis with endoscopic instruments were unsuccessful. The com kernel was retrieved via a tracheotomy incision. Endoscopy of the trachea 2 mo postoperatively showed complete healing of the tracheal incision. Mucosal integrity had been reestablished, and tracheal lumen diameter was not compromised. The bird continues in good health 2.5 yr after surgery, shows no signs of respiratory disease, and currently is in a captive breeding program. C1 US FISH & WILDLIFE SERV,NATL WILDLIFE HLTH RES CTR,MADISON,WI 53711. INT CRANE FDN,BARABOO,WI 53913. RP HOWARD, PE (reprint author), UNIV WISCONSIN,SCH VET MED,DEPT SURG SCI,MADISON,WI 53706, USA. NR 14 TC 8 Z9 8 U1 0 U2 0 PU AMER ASSOC Z00 VETERINARIANS PI MEDIA PA 6 NORTH PENNELL ROAD, MEDIA, PA 19063 SN 1042-7260 J9 J ZOO WILDLIFE MED JI J. Zoo Wildl. Med. PD SEP PY 1991 VL 22 IS 3 BP 359 EP 363 PG 5 WC Veterinary Sciences SC Veterinary Sciences GA GL344 UT WOS:A1991GL34400013 ER PT J AU BARTON, PB AF BARTON, PB TI ORE TEXTURES - PROBLEMS AND OPPORTUNITIES SO MINERALOGICAL MAGAZINE LA English DT Article; Proceedings Paper CT MEETING ON MINERAL TEXTURES CY SEP 03-04, 1990 CL UNIV MANCHESTER, MANCHESTER, ENGLAND SP MINERAL SOC, GEOL SOC HO UNIV MANCHESTER DE ORE DEPOSITS; TEXTURES; PHASE ASSEMBLAGES; SILICA; SPHALERITE ID ZN-S SYSTEM; CREEDE MINING DISTRICT; SAN-JUAN MOUNTAINS; CHALCOPYRITE DISEASE; SPHALERITE; ENVIRONMENT; DEPOSITION; COLORADO; ZINC AB Over the past several decades, thinking about chemical processes in rocks had been dominated by experimental and theoretical treatments of mineral equilibrium, which is the state from which the time variable has been excluded. But, to an extent exceeding that of any of our sister sciences, we in geology are concerned with the behaviour of things as a function of time; thus equilibrium is but one of several interesting boundary conditions. Textures, (defined as the spatial relations within and among minerals and fluids, regardless of scale or origin) provide a means to sort out and identify successive states. In fact, it is the pattern of evolution of those states that enables us to deduce the processes. We may well draw the analogy with thermodynamics and kinetics, respectively: equilibrium textures and phase assemblages, via thermodynamic analysis --> definition of conditions of equilibration, whereas kinetics, as displayed in disequilibrium textures --> sequence of events and processes of mineralization. The interpretation of textures is one of the most difficult yet important aspects of the study of rocks and ores, and there are few areas of scientific endeavour that are more subject to misinterpretation. Although the difficulties are many, the opportunites for new understanding are also abundant. Textural interpretations have many facets: some are well established and accepted; some that are accepted may be wrong; others are recognised to be speculative and controversial; and we trust that still other textural features remain to be described and interpreted. This paper will deal principally with low-temperature, epigenetic ore deposits, and will emphasise silica and sphalerite; but extension to other materials is not unreasonable. Ore and gangue minerals react internally, or with their environment, at widely ranging rates, ranging from the almost inert pyrite, arsenopyrite, well-crystallised quartz, and tourmaline to the notoriously fickle copper/iron and copper/silver sulfides. Arrested or incomplete reactions may be identified by textural criteria and, when appropriately quantified, can provide guides to the duration of geological processes. In recent years so much emphasis has been placed on isotopes, fluids, chemistry, and deposit and process models that the textural features have been ignored. In part this oversight occurs because we have grown accustomed to using superposition, cross-cutting, pseudomorphism, mutual intergrowths, exsolution and so on as off-the-shelf tools, to be grasped and applied without evaluation or even description. Surely science must build on previous work without constant and exhaustive reassessment, but for mineral textures a little reassessment may yield substantial benefit. RP BARTON, PB (reprint author), US GEOL SURVEY 959,RESTON,VA 22092, USA. NR 34 TC 16 Z9 16 U1 0 U2 0 PU MINERALOGICAL SOCIETY PI LONDON PA 41 QUEENS GATE, LONDON, ENGLAND SW7 5HR SN 0026-461X J9 MINERAL MAG JI Mineral. Mag. PD SEP PY 1991 VL 55 IS 380 BP 303 EP & DI 10.1180/minmag.1991.055.380.02 PG 0 WC Mineralogy SC Mineralogy GA GK663 UT WOS:A1991GK66300002 ER PT J AU MCKEAN, J BUECHEL, S GAYDOS, L AF MCKEAN, J BUECHEL, S GAYDOS, L TI REMOTE-SENSING AND LANDSLIDE HAZARD ASSESSMENT SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article; Proceedings Paper CT 8TH THEMATIC CONF ON GEOLOGIC REMOTE SENSING CY APR 29-MAY 02, 1991 CL DENVER, CO SP ENVIRONM RES INST MICHIGAN ID MAPPER SIMULATOR DATA AB Remotely acquired multispectral data are used to improve landslide hazard assessments at all scales of investigation. A vegetation map produced from automated interpretation of TM data is used in a GIS context to explore the effect of vegetation type on debris flow occurrence in preparation for inclusion in debris flow hazard modeling. Spectral vegetation indices map spatial patterns of grass senescence which are found to be correlated with soil thickness variations on hillslopes. Grassland senescence is delayed over deeper, wetter soils that are likely debris flow source areas. Prediction of actual soil depths using vegetation indices may be possible up to some limiting depth greater than the grass rooting zone. On forested earthflows, the slow slide movement disrupts the overhead timber canopy, exposes understory vegetation and soils, and alters site spectral characteristics. Both spectral and textural measures from broad band multispectral data are successful at detecting an earthflow within an undisturbed old-growth forest. C1 TGS INC,NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NASA,AMES RES CTR,US GEOL SURVEY,MOFFETT FIELD,CA 94035. RP MCKEAN, J (reprint author), US FOREST SERV,PLEASANT HILL,CA 94523, USA. RI McKean, Jim/C-3581-2011 NR 20 TC 35 Z9 37 U1 0 U2 6 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD SEP PY 1991 VL 57 IS 9 BP 1185 EP 1193 PG 9 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA GD546 UT WOS:A1991GD54600007 ER PT J AU DORN, RI PHILLIPS, FM ZREDA, MG WOLFE, EW JULL, AJT DONAHUE, DJ KUBIK, PW SHARMA, P AF DORN, RI PHILLIPS, FM ZREDA, MG WOLFE, EW JULL, AJT DONAHUE, DJ KUBIK, PW SHARMA, P TI GLACIAL CHRONOLOGY SO RESEARCH & EXPLORATION LA English DT Article ID ROCK VARNISH; COSMOGENIC CHLORINE-36; AGES; ORIGIN; INSITU; C-14 AB Since S. C. Porter completed his classic stratigraphic study (1979) of the glaciation of Mauna Kea, Hawaii, new surface-exposure dating techniques have been developed to estimate ages of Quaternary glacial events. Our rock varnish, cosmogenic Cl-36 buildup, C-14 dating of organics in silica skins, and in situ C-14 results affirm Porter's glacial sequence. The Makanaka glaciation lasted from approximately 40 ka to approximately 13 ka, but glacial retreat begun by approximately 18 ka was almost complete by approximately 15 ka. We place the Waihu glaciation during the early Wisconsin (oxygen-isotope stage 4) based on exposure ages of approximately 60 to 70 ka, and the Pohakuloa glaciation in oxygen-isotope stage 6 based on exposure ages of >132 to 163 ka. C1 ARIZONA STATE UNIV,DEPT GEOG,TEMPE,AZ 85287. NEW MEXICO INST MIN & TECHNOL,DEPT GEOSCI,SOCORRO,NM 87801. US GEOL SURVEY,DAVID A JOHNSTON CASCADE VOLCANO OBSERV,VANCOUVER,WA 98661. UNIV ARIZONA,DEPT PHYS,TUCSON,AZ 85721. UNIV ROCHESTER,NUCL STRUCT RES LAB,ROCHESTER,NY 14627. NR 33 TC 0 Z9 1 U1 0 U2 0 PU NATL GEOGRAPHIC SOC PI WASHINGTON PA 17TH AND M STS NW, WASHINGTON, DC 20036 SN 8755-724X J9 RES EXPLOR JI Res. Explor. PD FAL PY 1991 VL 7 IS 4 BP 456 EP 471 PG 16 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LE780 UT WOS:A1991LE78000010 ER PT J AU FIO, JL FUJII, R DEVEREL, SJ AF FIO, JL FUJII, R DEVEREL, SJ TI SELENIUM MOBILITY AND DISTRIBUTION IN IRRIGATED AND NONIRRIGATED ALLUVIAL SOILS SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID SAN-JOAQUIN VALLEY; SHALLOW GROUNDWATER; ADSORPTION; CALIFORNIA; SELENATE AB Dissolution and leaching of soil salts by irrigation water is a primary source of Se to shallow groundwater in the western San Joaquin Valley, California. In this study, the mobility and distribution of selenite and selenate in soils with different irrigation and drainage histories was evaluated using sorption experiments and an advection-dispersion model. The sorption studies showed that selenate (15-12 400-mu-g Se L-1) is not adsorbed to soil, whereas selenite (10-5000-mu-g Se L-1) is rapidly adsorbed. The time lag between adsorption and desorption of selenite is considerable, indicating a dependence of reaction rate on reaction direction (hysteresis). Selenite adsorption and desorption isotherms were different, and both were described with the Freundlich equation. Model results and chemical analyses of extracts from the soil samples showed that selenite is resistant to leaching and therefore can represent a potential long-term source of Se to groundwater. In contrast, selenate behaves as a conservative constituent under alkaline and oxidized conditions and is easily leached from soil. RP FIO, JL (reprint author), US GEOL SURVEY,RM W-2234,FED BLDG,2800 COTTAGE WAY,SACRAMENTO,CA 95825, USA. NR 32 TC 29 Z9 33 U1 2 U2 10 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD SEP-OCT PY 1991 VL 55 IS 5 BP 1313 EP 1320 PG 8 WC Soil Science SC Agriculture GA GL876 UT WOS:A1991GL87600020 ER PT J AU BJORNN, TC KIRKING, SC MEEHAN, WR AF BJORNN, TC KIRKING, SC MEEHAN, WR TI RELATION OF COVER ALTERATIONS TO THE SUMMER STANDING CROP OF YOUNG SALMONIDS IN SMALL SOUTHEAST ALASKA STREAMS SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID JUVENILE COHO SALMON; HABITAT AB Summer abundance of young coho salmon Oncorhynchus kisutch, steelhead O. mykiss, and Dolly Varden Salvelinus malma was assessed in small streams on Prince of Wales Island, Alaska, in an attempt to measure the response of these fish to various types of cover alterations. The standing crop of subyearlings decreased during summer, but none of the decrease could be attributed to the changes in cover we made. Subyearling coho salmon (about 75% of the fish present) did not respond either to the removal of natural riparian vegetation or to the addition of simulated riparian canopy, large boulders, woody debris, or simulated undercut banks. Localized movements within the streams were sufficient to provide relatively rapid recolonization of the experimental habitat units. The forms of cover we evaluated were relatively unimportant in regulating abundance of young coho salmon in small streams. C1 PACIFIC NW RES STN,FORESTRY SCI LAB,JUNEAU,AK 99801. RP BJORNN, TC (reprint author), UNIV IDAHO,US FISH & WILDLIFE SERV,IDAHO COOPERAT FISH & WILDLIFE RES UNIT,MOSCOW,ID 83843, USA. NR 23 TC 9 Z9 10 U1 0 U2 3 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD SEP PY 1991 VL 120 IS 5 BP 562 EP 570 DI 10.1577/1548-8659(1991)120<0562:ROCATT>2.3.CO;2 PG 9 WC Fisheries SC Fisheries GA GZ023 UT WOS:A1991GZ02300003 ER PT J AU GROST, RT HUBERT, WA WESCHE, TA AF GROST, RT HUBERT, WA WESCHE, TA TI DESCRIPTION OF BROWN TROUT REDDS IN A MOUNTAIN STREAM SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID BROOK TROUT; SALMON; RIVER AB We sampled redds of brown trout Salmo trutta in a mountain stream to describe egg location and substrate composition after spawning and during egg incubation. A single-probe freeze-coring device was used to sample egg depth and substrate composition. We found eggs throughout redds but most often in the front half of the tailspill (the substrate mound that accumulates as the redd is excavated progressively upstream). Eggs were buried between 2 and 23 cm below the substrate surface but were most frequently 9-12 cm deep. Spawning fish cleaned substrate particles less than 6.3 mm in diameter from egg pockets, yet the percentage of particles smaller than 1.7 mm in egg pockets was correlated with that outside redds. Egg pockets contained particles larger than 50 mm more often than did any other location, indicating that particles of this size were used as egg pocket centrums. The percentage of 1.7-mm and smaller particles in egg pockets was higher in winter than in fall. We conclude that (1) spawning brown trout 20-40 cm in total length substantially alter the substrate in egg pockets; (2) the amount of fine sediment in egg pockets is positively correlated with that in the adjacent streambed; and (3) fines accumulate in egg pockets during the incubation period. C1 UNIV WYOMING,DEPT ZOOL & PHYSIOL,US FISH & WILDLIFE SERV,LARAMIE,WY 82071. UNIV WYOMING,DEPT RANGE MANAGEMENT,LARAMIE,WY 82071. NR 22 TC 36 Z9 37 U1 1 U2 2 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD SEP PY 1991 VL 120 IS 5 BP 582 EP 588 DI 10.1577/1548-8659(1991)120<0582:DOBTRI>2.3.CO;2 PG 7 WC Fisheries SC Fisheries GA GZ023 UT WOS:A1991GZ02300005 ER PT J AU GUSTAVESON, AW WYDOSKI, RS WEDEMEYER, GA AF GUSTAVESON, AW WYDOSKI, RS WEDEMEYER, GA TI PHYSIOLOGICAL-RESPONSE OF LARGEMOUTH BASS TO ANGLING STRESS SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID MICROPTERUS-SALMOIDES AB The physiological effects of catch-and-release fishing on largemouth bass Micropterus salmoides from Lake Powell and Mantua Reservoir, Utah, were evaluated, and an estimate of the time needed for recovery from hooking stress was obtained. Fatigue in Lake Powell fish, as indicated by elevated blood lactate, was directly proportional to hooking time (1-5 min) and water temperature, but recovery from the hyperlacticemia was relatively rapid (about 24 h). Hyperglycemia, an indicator of stress hormone production, did not occur in largemouth bass hooked and played for 1-5 min in the coldest water (11-13-degrees-C), was moderate in fish hooked and played at 16-20-degrees-C, and was severe in fish played for 5 min at 28-30-degrees-C. Fish held for recovery in live cages suffered further hyperglycemia, presumably because of the stress of confinement. Ionoregulation, as indicated by relatively stable plasma chloride values, was not immediately affected in largemouth bass caught at water temperatures of 11-13-degrees-C or 28-30-degrees-C, but an unusual hyperchloremia developed in fish hooked and played at 16-20-degrees-C. During recovery, the expected progressive hypochloremia developed. Plasma osmolality was somewhat affected by hooking at all water temperatures tested, but recovery was almost complete within about 8 h. Mantua Reservoir fish were hooked and played only at water temperatures of 23-26-degrees-C. The hyperlacticemia and hyperglycemia that occurred were generally more severe than in the Lake Powell fish hooked and played at either 16-20-degrees-C or 28-30-degrees-C. However, effects on plasma chloride and osmolality were similar to those occurring in Lake Powell fish. C1 UTAH STATE UNIV,US FISH & WILDLIFE SERV,UTAH COOPERAT FISH & WILDLIFE RES UNIT,LOGAN,UT 84322. US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,SEATTLE,WA 98115. NR 31 TC 82 Z9 84 U1 4 U2 15 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD SEP PY 1991 VL 120 IS 5 BP 629 EP 636 DI 10.1577/1548-8659(1991)120<0629:PROLBT>2.3.CO;2 PG 8 WC Fisheries SC Fisheries GA GZ023 UT WOS:A1991GZ02300010 ER PT J AU SWINK, WD AF SWINK, WD TI HOST-SIZE SELECTION BY PARASITIC SEA LAMPREYS SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID PETROMYZON-MARINUS PREDATION; TROUT SALVELINUS-NAMAYCUSH; LAKE TROUT; ONTARIO AB When 171 sea lampreys Petromyzon marinus were each offered a onetime choice of one large and two small lake trout Salvelinus namaycush, the ratio of their attacks (49.1%:27.5%: 23.4%) was similar to the ratio of host surface areas (51.4%:26.3%:22.3%) in laboratory tests conducted over 9 months in 1988-1989. When the smallest offered host was 560 mm total length (TL) or shorter, sea lampreys attacked the smallest host less often and the largest host more often than expected (N = 39) under assumptions that attacks would be either equal among the hosts (numbers-dependent hypothesis) or proportional to the hosts' surface areas (area-dependent hypothesis). When the smallest host was 615 mm TL or longer, observed attacks (N = 132) did not differ significantly from the number of attacks expected by either the numbers-dependent or the area-dependent hypothesis; however, the largest lake trout was almost always attacked more often than either of the smaller fish. These results are similar to field observations that sea lampreys kill few lake trout smaller than about 600 mm TL when larger fish are available as hosts, and that they attack larger fish (673-775+ mm TL) at a progressively greater rate as host size increases. Sea lamprey host-size selection was less pronounced in this study than in previous laboratory studies, which used smaller host fish than those now available in the Great Lakes. RP SWINK, WD (reprint author), US FISH & WILDLIFE SERV,NATL FISHERY RES CTR,HAMMOND BAY BIOL STN,11188 RAY RD,MILLERSBURG,MI 49759, USA. NR 20 TC 32 Z9 34 U1 8 U2 14 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD SEP PY 1991 VL 120 IS 5 BP 637 EP 643 DI 10.1577/1548-8659(1991)120<0637:HSBPSL>2.3.CO;2 PG 7 WC Fisheries SC Fisheries GA GZ023 UT WOS:A1991GZ02300011 ER PT J AU DENNING, AS BARON, J MAST, MA ARTHUR, M AF DENNING, AS BARON, J MAST, MA ARTHUR, M TI HYDROLOGIC PATHWAYS AND CHEMICAL-COMPOSITION OF RUNOFF DURING SNOWMELT IN LOCH VALE WATERSHED, ROCKY-MOUNTAIN-NATIONAL-PARK, COLORADO, USA SO WATER AIR AND SOIL POLLUTION LA English DT Article ID CHEMISTRY; LAKES; ALUMINUM; DEPOSITION; MELTWATER; SNOWPACK; STREAMS; MODEL; BROOK AB Intensive sampling of a stream draining an alpine-subalpine basin revealed that depressions in pH and acid neutralizing capacity (ANC) of surface water at the beginning of the spring snowmelt in 1987 and 1988 were not accompanied by increases in strong acid anions, and that surface waters did not become acidic (ANC < 0). Samples of meltwater collected at the base of the snowpeak in 1987 were acidic and exhibited distinct 'pulses' of nitrate and sulfate. Solutions collected with lysimeters in forest soils adjacent to the stream revealed high levels of dissolved organic carbon (DOC) and total Al. Peaks in concentration of DOC, Al, and nutrient species in the stream samples indicate a flush of soil solution into the surface water at the beginning of the melt. Infiltration of meltwater into soils and spatial heterogeneity in the timing of melting across the basin prevented stream and lake waters from becoming acidic. C1 COLORADO STATE UNIV,NAT RESOURCE ECOL LAB,FT COLLINS,CO 80523. NATL PK SERV,DIV WATER RESOURCES,FT COLLINS,CO 80526. US GEOL SURVEY,RESTON,VA 22092. CORNELL UNIV,ITHACA,NY 14853. RI Baron, Jill/C-5270-2016 OI Baron, Jill/0000-0002-5902-6251 NR 39 TC 45 Z9 45 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0049-6979 J9 WATER AIR SOIL POLL JI Water Air Soil Pollut. PD SEP PY 1991 VL 59 IS 1-2 BP 107 EP 123 PG 17 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Water Resources SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Water Resources GA GP465 UT WOS:A1991GP46500008 ER PT J AU CRAWFORD, CG WANGSNESS, DJ AF CRAWFORD, CG WANGSNESS, DJ TI EFFECTS OF ADVANCED WASTE-WATER TREATMENT ON THE QUALITY OF WHITE RIVER, INDIANA SO WATER RESOURCES BULLETIN LA English DT Article DE ADVANCED WASTE-WATER TREATMENT; AMMONIA; BIOCHEMICAL OXYGEN DEMAND; DISSOLVED OXYGEN; NITRATE; STATISTICAL ANALYSIS; RIVER WATER QUALITY; WATER SEWAGE TREATMENT AB In 1983, the City of Indianapolis, Indiana, completed construction of advanced wastewater treatment (AWT) systems to enlarge and upgrade its existing Belmont Road and Southport Road secondary treatment plants. A nonparametric statistical procedure, a modified form of the Wilcoxon-Mann-Whitney rank-sum test, was used to test for trends in water quality at two upstream and two downstream sites on White River and at the two treatment plants. Results comparing the pre- (1978-1980) and post- (1983-1986) AWT periods show statistically significant improvements in the quality of the treated effluent and of the White River downstream from the plants. Water quality at sites upstream from the city was relatively constant during the period of study. Total ammonia (as N) decreased 14.6 mg/L and BOD5 (five-day biochemical oxygen demand) decreased 10 to 19 mg/L in the two effluents. Total ammonia in the river downstream from the plants decreased 0.8 to 1.9 mg/L and BOD5 decreased 2.3 to 2.5 mg/L. Nitrate (as N) increased 14.5 mg(L in the plant effluents and 2.0 to 2.4 mg/L in the river because of in-plant nitrification. Dissolved oxygen concentration in the river increased about 3 mg/L because of reduced oxygen demand for nitrification and biochemical oxidation processes. C1 US GEOL SURVEY,DORAVILLE,GA 30360. RP CRAWFORD, CG (reprint author), US GEOL SURVEY,5957 LAKESIDE BLVD,INDIANAPOLIS,IN 46278, USA. OI Crawford, Charles/0000-0003-1653-7841 NR 13 TC 9 Z9 9 U1 1 U2 1 PU AMER WATER RESOURCES ASSOC PI HERNDON PA 950 HERNDON PARKWAY SUITE 300, HERNDON, VA 20170-5531 SN 0043-1370 J9 WATER RESOUR BULL JI Water Resour. Bull. PD SEP-OCT PY 1991 VL 27 IS 5 BP 769 EP 779 PG 11 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA HG397 UT WOS:A1991HG39700005 ER PT J AU DEVEREL, SJ FIO, JL AF DEVEREL, SJ FIO, JL TI GROUNDWATER-FLOW AND SOLUTE MOVEMENT TO DRAIN LATERALS, WESTERN SAN JOAQUIN VALLEY, CALIFORNIA .1. GEOCHEMICAL ASSESSMENT SO WATER RESOURCES RESEARCH LA English DT Article ID SHALLOW GROUNDWATER; SELENIUM AB A study was undertaken to quantitatively evaluate the hydrologic processes affecting the chemical and isotopic composition of drain lateral water in a drained agricultural field in the western San Joaquin Valley, California. The results elucidate the process of mixing of deep and shallow groundwater (below and within 6 m from land surface) entering the drain laterals. The deep groundwater was subject to evapoconcentration prior to drainage system installation and has been displaced downward (to depths greater than 6 m) in the groundwater system. The proportions of deep and shallow groundwater entering the drain laterals was calculated from the end-member oxygen 18 compositions determined in groundwater samples. The percentage of total drain lateral flow which is deep groundwater flow is about 30% for the shallow drain lateral (1.8 m below land surface) (drain lateral 1)) and 60% for the deep drain lateral (2.7 m below land surface (drain lateral 2)). During irrigation, the percentages of deep groundwater flow decrease to 0 and 30% for the shallow and deep drain laterals, respectively. Selenium concentrations in drain lateral waters decrease during irrigation but selenium loads increase. Total estimated annual loads were 1.1 and 5.4 kg of selenium for drain laterals 1 and 2, respectively. Substantial percentages of the annual load occurred during 8 days of irrigation, 23 and 9% for drain laterals 1 and 2, respectively. RP DEVEREL, SJ (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,2800 COTTAGE WAY,SACRAMENTO,CA 95825, USA. NR 28 TC 14 Z9 14 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD SEP PY 1991 VL 27 IS 9 BP 2233 EP 2246 DI 10.1029/91WR01367 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA GD927 UT WOS:A1991GD92700006 ER PT J AU FIO, JL DEVEREL, SJ AF FIO, JL DEVEREL, SJ TI GROUNDWATER-FLOW AND SOLUTE MOVEMENT TO DRAIN LATERALS, WESTERN SAN JOAQUIN VALLEY, CALIFORNIA .2. QUANTITATIVE HYDROLOGIC ASSESSMENT SO WATER RESOURCES RESEARCH LA English DT Article ID SHALLOW GROUNDWATER; SELENIUM; FIELDS AB Groundwater flow modeling was used to quantitatively assess the hydrologic processes affecting groundwater and solute movement to drain laterals. Modeling results were used to calculate the depth distribution of groundwater flowing into drain laterals at 1.8 m (drain lateral 1) and 2.7 m (drain lateral 2) below land surface. The simulations indicated that under nonirrigated conditions about 89% of the flow in drain lateral 2 was from groundwater originating from depths greater than 6 m below land surface. The deep groundwater has higher selenium concentrations than shallow groundwater. Simulation of irrigated conditions indicates that as recharge (deep percolation) increases, the proportional contribution of deep groundwater to drain lateral flow decreases. Groundwater flow paths and travel times estimated from the simulation results indicate that groundwater containing high concentrations of selenium (greater than 780-mu-g L-1) probably will continue to enter drain lateral 2 for decades. RP FIO, JL (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,2800 COTTAGE WAY,SACRAMENTO,CA 95825, USA. NR 21 TC 10 Z9 10 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD SEP PY 1991 VL 27 IS 9 BP 2247 EP 2257 DI 10.1029/91WR01368 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA GD927 UT WOS:A1991GD92700007 ER PT J AU POLLMAN, CD LEE, TM ANDREWS, WJ SACKS, LA GHERINI, SA MUNSON, RK AF POLLMAN, CD LEE, TM ANDREWS, WJ SACKS, LA GHERINI, SA MUNSON, RK TI PRELIMINARY-ANALYSIS OF THE HYDROLOGIC AND GEOCHEMICAL CONTROLS ON ACID-NEUTRALIZING CAPACITY IN 2 ACIDIC SEEPAGE LAKES IN FLORIDA SO WATER RESOURCES RESEARCH LA English DT Article ID WATER; ACIDIFICATION; UNCERTAINTIES; COLORADO AB In late 1988, parallel studies of Lake Five-O (pH 5.14) in the Florida panhandle and Lake Barco (pH 4.50) in north central Florida were initiated to develop hydrologic and major ion budgets of these lakes as part of an overall effort to improve understanding of the hydrologic, depositional, and biogeochemical factors that control acid-neutralizing capacity (ANC) in seepage lakes. Preliminary findings from these studies indicate that earlier perceptions of lake hydrology and mechanisms of ANC regulation in Florida seepage lakes may have to be revised. The traditional perspective of seepage lakes in the Florida panhandle views these systems as dominated by precipitation inputs and that ANC regulation is due largely to in-lake processes. Our results for Lake Five-O show modest to steep hydraulic gradients almost entirely around the lake. In addition, the horizontal hydraulic conductivity of the surficial aquifer is high (8-74 m day-1), indicating that large quantities of groundwater flow into Lake Five-O. Calculations of net groundwater flow from hydrologic budgets also indicate that groundwater may comprise at least 38 to 46% of the total inflow. For Lake Barco, net flow estimates of the minimum groundwater inflow range from 5 to 14% of total inflow. Enrichment factor and ion flux calculations for Lake Five-O and Lake Barco indicate that terrestrial as well as in-lake processes contribute significantly to ANC regulation. The extent that terrestrial processes contribute to ANC generation is directly related to the magnitude of groundwater inflow as well as the degree of ion enrichment or depletion that occurs in the surficial aquifer. Net ANC generation in both study lakes was dominated by anion retention (NO3- and SO4(2-)). Where previous studies concluded that in-lake reduction was the primary sink for SO4(2-), our preliminary calculations show that adsorption of SO4(2-) within the watershed is perhaps twice as important as in-lake reduction as a source of ANC. Net base cation enrichment in both lakes was negligible. C1 US GEOL SURVEY,TALLAHASSEE,FL 32301. TETRA TECH INC,LAFAYETTE,CA 94549. US GEOL SURVEY,TAMPA,FL 33634. RP POLLMAN, CD (reprint author), KBN ENGN & APPL SCI INC,1034 NW 57TH ST,GAINESVILLE,FL 32605, USA. NR 46 TC 22 Z9 22 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD SEP PY 1991 VL 27 IS 9 BP 2321 EP 2335 DI 10.1029/91WR01435 PG 15 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA GD927 UT WOS:A1991GD92700012 ER PT J AU MOYER, LM GEISSLER, PH AF MOYER, LM GEISSLER, PH TI ACCOMMODATING OUTLIERS IN WILDLIFE SURVEYS SO WILDLIFE SOCIETY BULLETIN LA English DT Article RP MOYER, LM (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD FAL PY 1991 VL 19 IS 3 BP 267 EP 270 PG 4 WC Biodiversity Conservation SC Biodiversity & Conservation GA GJ338 UT WOS:A1991GJ33800004 ER PT J AU LEFEBVRE, LW KOCHMAN, HI AF LEFEBVRE, LW KOCHMAN, HI TI AN EVALUATION OF AERIAL SURVEY REPLICATE COUNT METHODOLOGY TO DETERMINE TRENDS IN MANATEE ABUNDANCE SO WILDLIFE SOCIETY BULLETIN LA English DT Article ID VISIBILITY BIAS; TRICHECHUS-MANATUS; CAPTURE-RECAPTURE; FLORIDA; FAUNA RP US FISH & WILDLIFE SERV, 412 NE 16TH AVE, ROOM 250, GAINESVILLE, FL 32601 USA. NR 31 TC 8 Z9 8 U1 0 U2 3 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1938-5463 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD FAL PY 1991 VL 19 IS 3 BP 298 EP 309 PG 12 WC Biodiversity Conservation SC Biodiversity & Conservation GA GJ338 UT WOS:A1991GJ33800009 ER PT J AU JOHNSON, BK LINDZEY, FG GUENZEL, RJ AF JOHNSON, BK LINDZEY, FG GUENZEL, RJ TI USE OF AERIAL LINE TRANSECT SURVEYS TO ESTIMATE PRONGHORN POPULATIONS IN WYOMING SO WILDLIFE SOCIETY BULLETIN LA English DT Article C1 WYOMING GAME & FISH DEPT,BUFFALO,WY 82834. UNIV WYOMING,US FISH & WILDLIFE SERV,WYOMING COOPERAT FISH & WILDLIFE RES UNIT,LARAMIE,WY 82071. WYOMING GAME & FISH DEPT,CASPER,WY 82604. NR 11 TC 23 Z9 26 U1 0 U2 2 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD FAL PY 1991 VL 19 IS 3 BP 315 EP 321 PG 7 WC Biodiversity Conservation SC Biodiversity & Conservation GA GJ338 UT WOS:A1991GJ33800011 ER PT J AU PERRY, MC AF PERRY, MC TI UHLER,FRANCIS,MOREY 1902-1990 SO WILDLIFE SOCIETY BULLETIN LA English DT Item About an Individual RP PERRY, MC (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD FAL PY 1991 VL 19 IS 3 BP 375 EP 377 PG 3 WC Biodiversity Conservation SC Biodiversity & Conservation GA GJ338 UT WOS:A1991GJ33800021 ER PT J AU NUCCIO, VF AF NUCCIO, VF TI COMBINING METHODS YIELDS BEST SOURCE ROCK MATURITY SO WORLD OIL LA English DT Article RP NUCCIO, VF (reprint author), US GEOL SURVEY,DENVER,CO 80225, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU GULF PUBL CO PI HOUSTON PA BOX 2608, HOUSTON, TX 77252-2608 SN 0043-8790 J9 WORLD OIL JI World Oil PD SEP PY 1991 VL 212 IS 9 BP 63 EP & PG 0 WC Energy & Fuels SC Energy & Fuels GA GF238 UT WOS:A1991GF23800008 ER PT J AU BOUCHARD, M PAVICH, MJ AF BOUCHARD, M PAVICH, MJ TI CHARACTERISTICS AND SIGNIFICANCE OF PRE-WISCONSINAN SAPROLITES IN THE NORTHERN APPALACHIANS - DISCUSSION - REPLY SO ZEITSCHRIFT FUR GEOMORPHOLOGIE LA English DT Article C1 US GEOL SURVEY,RESTON,VA 22092. RP BOUCHARD, M (reprint author), UNIV QUEBEC,DEPT GEOG,CP 8888,SUCC A,MONTREAL H3C 3P8,QUEBEC,CANADA. NR 11 TC 2 Z9 2 U1 0 U2 4 PU GEBRUDER BORNTRAEGER PI STUTTGART PA JOHANNESSTR 3A, D-70176 STUTTGART, GERMANY SN 0372-8854 J9 Z GEOMORPHOL JI Z. Geomorphol. PD SEP PY 1991 VL 35 IS 3 BP 373 EP 377 PG 5 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA GF859 UT WOS:A1991GF85900009 ER PT J AU COLLOT, JY GREENE, HG STOKKING, L AKIMOTO, K ASK, MVS BAKER, PE BRIQUEU, L CHABERNAUD, T COLTORTI, M FISHER, MA GOUD, M HASENAKA, T HOBART, M KRAMMER, A LEONARD, J MARTIN, JB MARTINEZRODRIGEZ, JJ MENGER, S MESCHEDE, M PELLETIER, B PEREMBO, RCB QUINN, TM ROPERCH, P REID, P RIEDEL, WR STAERKER, TS TAYLOR, FW ZHAO, X AF COLLOT, JY GREENE, HG STOKKING, L AKIMOTO, K ASK, MVS BAKER, PE BRIQUEU, L CHABERNAUD, T COLTORTI, M FISHER, MA GOUD, M HASENAKA, T HOBART, M KRAMMER, A LEONARD, J MARTIN, JB MARTINEZRODRIGEZ, JJ MENGER, S MESCHEDE, M PELLETIER, B PEREMBO, RCB QUINN, TM ROPERCH, P REID, P RIEDEL, WR STAERKER, TS TAYLOR, FW ZHAO, X TI PRELIMINARY-RESULTS OF ODP LEG 134 IN THE COLLISION ZONE BETWEEN THE NEW-HEBRIDES ISLAND-ARC AND THE DENTRECASTEAUX ZONE SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE II LA French DT Article ID SUBDUCTION; VANUATU; PACIFIC; CRUISE AB Results of ODP Leg 134 indicate that the eastern d'Entrecasteaux zone (DEZ) is an immature intra-oceanic island arc along which subduction ceased prior to the Late Oligocene and that the DEZ emerged several times before the Late Pliocene or Early Pleistocene. The sedimentary cover of the North d'Entrecasteaux Ridge (NDR), which is part of the DEZ, is tectonically accreted at the toe of the inner wall of the New Hebrides trench and undergoes severe dewatering. Within the accreted rocks fluids appear to concentrate along thrust zones. Directly east of the collision, the intra-arc North Aoba basin underwent a major tectonic event during the Late Pliocene or Early Pleistocene. During the Pleistocene, the axis of the basin migrated westward towards its present location. These events can be attributed to the DEZ-arc collision. C1 US GEOL SURVEY,MENLO PK,CA 94025. ODP,COLLEGE STN,TX 77845. RP COLLOT, JY (reprint author), ORSTOM,BP 48,F-06230 VILLEFRANCHE MER,FRANCE. RI Taylor, Frederick/A-2195-2009; Pelletier, Bernard/J-8106-2016 OI Pelletier, Bernard/0000-0002-9993-1395 NR 20 TC 0 Z9 0 U1 0 U2 0 PU GAUTHIER-VILLARS PI PARIS PA S P E S-JOURNAL DEPT, 120 BD ST GERMAIN, F-75006 PARIS, FRANCE SN 1251-8069 J9 CR ACAD SCI II PD AUG 29 PY 1991 VL 313 IS 5 BP 539 EP 546 PG 8 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA GD399 UT WOS:A1991GD39900010 ER PT J AU LOVLEY, DR PHILLIPS, EJP GORBY, YA LANDA, ER AF LOVLEY, DR PHILLIPS, EJP GORBY, YA LANDA, ER TI MICROBIAL REDUCTION OF URANIUM SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,DIV WATER RESOURCES,RESTON,VA 22092. NR 0 TC 2 Z9 2 U1 2 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 25 PY 1991 VL 202 BP 8 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA HG080 UT WOS:A1991HG08001932 ER PT J AU SANDERS, PF THORNTON, LL LOUIS, JB IVAHNENKO, T EVANS, BM AF SANDERS, PF THORNTON, LL LOUIS, JB IVAHNENKO, T EVANS, BM TI USING A GEOGRAPHICAL INFORMATION-SYSTEM TO ASSESS THE SUSCEPTIBILITY OF SURFACE DRINKING-WATER SUPPLIES TO PESTICIDE CONTAMINATION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NEW JERSEY DEPT ENVIRONM PROTECT,TRENTON,NJ 08625. US GEOL SURVEY,W TRENTON,NJ 08628. GEO DECIS INC,LEMONT,PA 16851. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 25 PY 1991 VL 202 BP 53 EP AGRO PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA HG080 UT WOS:A1991HG08000267 ER PT J AU TANAKA, KL GOLOMBEK, MP BANERDT, WB AF TANAKA, KL GOLOMBEK, MP BANERDT, WB TI RECONCILIATION OF STRESS AND STRUCTURAL HISTORIES OF THE THARSIS REGION OF MARS SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID LITHOSPHERIC STRESS; VALLES MARINERIS; MAGMATIC SYSTEMS; TECTONIC HISTORY; RIDGED PLAINS; GROUND ICE; GEOMETRY; GRAVITY; THICKNESS; PROVINCE AB We present a new compilation of the structural and stratigraphic evolution of the Tharsis region of Mars that incorporates recent advances in understanding its stratigraphy, and we introduce a lithospheric deformation model that can account for the observations. The first period in the formation of Tharsis occurred in Late Noachian/Early Hesperian time with the deposition of volcanic plains materials throughout the surrounding highlands (e.g., Lunae Planum) and on the Tharsis rise (which includes the giant volcanoes and surrounding, elevated lava fields). Extensive radial normal faulting occurred on the rise, locally extending outward at Valles Marineris and Tempe Terra, and concentric wrinkle ridges formed along the edge of the rise. This regional deformation appears to have been modulated by a global compressional stress field due to rapid planetary cooling and contraction. The second period occurred during the Late Hesperian/Amazonian with Tharsis volcanism centered on the rise and radial extensional deformation that extended from the center of the rise for thousands of kilometers. We propose a model in which the lithosphere beneath Tharsis consists of a thin elastic crustal cap on the rise that is mechanically detached from the strong upper mantle by a volcanically thickened, hot, weak lower crust. These layers merge into a single cooler, strong lithospheric layer around the edges of the rise. This model is capable of generating large extensional hoop stresses throughout much of the western hemisphere, in agreement with observations. The tectonic interpretation of the stresses predicted by this model requires the reconciliation of extensional strain within narrow grabens and compressional strain within wrinkle ridges with (1) processes in the deeper lithosphere, (2) the sparsity of strike-slip faults, and (3) other global or locally important stress fields. Stresses predicted by global models affect the entire thickness of the lithosphere, and they can be reconciled with narrow, closely spaced grabens that accommodate large amounts of extensional strain in the upper few kilometers of the lithosphere if the grabens are underlain and kinematically linked with dikes or other tension cracks, such as hydrofractures. Deeper levels of the lithosphere can accommodate this strain by elastic expansion if grabens are spaced far apart (many tens to hundreds of kilometers). Mechanical considerations suggest that deformation on faults beneath wrinkle ridges could extend through a significant thickness of the brittle crust. A number of factors, including stresses generated by the addition of overburden, intrusion of dikes, weakness of geologic materials under extension, and the laterally constrained nature of a single lithospheric plate, may have inhibited the formation of strike-slip faults on Mars. Stresses generated from the removal of overburden could have augmented planetwide wrinkle ridge formation during the Late Noachian/Early Hesperian and in Kasei Valles and western Chryse Planitia during the Early Amazonian. The nonuniform distribution of tectonic features around Tharsis can be understood in terms of the concentration of regional stresses and strain near weaker volcanotectonic centers. C1 CALTECH,JET PROP LAB,PASADENA,CA 91109. RP TANAKA, KL (reprint author), US GEOL SURVEY,2255 GEMINI DR,FLAGSTAFF,AZ 86001, USA. NR 82 TC 110 Z9 110 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD AUG 25 PY 1991 VL 96 IS E1 BP 15617 EP 15633 DI 10.1029/91JE01194 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GH507 UT WOS:A1991GH50700006 ER PT J AU BREIT, GN WANTY, RB AF BREIT, GN WANTY, RB TI VANADIUM ACCUMULATION IN CARBONACEOUS ROCKS - A REVIEW OF GEOCHEMICAL CONTROLS DURING DEPOSITION AND DIAGENESIS SO CHEMICAL GEOLOGY LA English DT Review ID MID-ATLANTIC RIDGE; TRACE-METALS; OIL SHALES; DISSOLVED VANADIUM; MEDITERRANEAN-SEA; SEDIMENTARY-ROCKS; NORTH PACIFIC; PORE WATER; CHEMISTRY; PARTICLES AB Published data relevant to the geochemistry of vanadium were used to evaluate processes and conditions that control vanadium accumulation in carbonaceous rocks. Reduction, adsorption, and complexation of dissolved vanadium favor addition of vanadium to sediments rich in organic carbon. Dissolved vanadate (V(V)) species predominate in oxic seawater and are reduced to vanadyl ion (V(IV)) by organic compounds or H2S. Vanadyl ion readily adsorbs to particle surfaces and is added to the sediment as the particles settle. The large vanadium concentrations of rocks deposited in marine as compared to lacustrine environments are the result of the relatively large amount of vanadium provided by circulating ocean water compared to terrestrial runoff. Vanadium-rich carbonaceous rocks typically have high contents of organically bound sulfur and are stratigraphically associated with phosphate-rich units. A correspondence between vanadium content and organically bound sulfur is consistent with high activities of H2S during sediment deposition. Excess H2S exited the sediment into bottom waters and favored reduction of dissolved V(V) to V(IV) or possibly V(III). The stratigraphic association of vanadiferous and phosphatic rocks reflects temporal and spatial shifts in bottom water chemistry from suboxic (phosphate concentrated) to more reducing (euxinic?) conditions that favor vanadium accumulation. During diagenesis some vanadium-organic complexes migrate with petroleum out of carbonaceous rocks, but significant amounts of vanadium are retained in refractory organic matter or clay minerals. As carbon in the rock evolves toward graphite during metamorphism, vanadium is incorporated into silicate minerals. RP BREIT, GN (reprint author), US GEOL SURVEY,BOX 25046,MS916,DENVER,CO 80225, USA. NR 102 TC 177 Z9 195 U1 1 U2 38 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD AUG 20 PY 1991 VL 91 IS 2 BP 83 EP 97 DI 10.1016/0009-2541(91)90083-4 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GG630 UT WOS:A1991GG63000002 ER PT J AU GRIFFITH, MB PERRY, SA AF GRIFFITH, MB PERRY, SA TI LEAF PACK PROCESSING IN 2 APPALACHIAN MOUNTAIN STREAMS DRAINING CATCHMENTS WITH DIFFERENT MANAGEMENT HISTORIES SO HYDROBIOLOGIA LA English DT Article DE LEAF PROCESSING; DECOMPOSITION; CATCHMENT DISTURBANCE; STREAM ECOLOGY; SHREDDERS ID WOODLAND STREAM; BREAKDOWN; DISTURBANCE; SHREDDER; LITTER; MODEL AB Rates of leaf litter processing and densities of macroinvertebrates in leaf packs were compared at two sites that differed in catchment logging history. The processing rate of leaves of sugar maple (Acer saccharum Marsh.) was significantly faster in a stream draining a catchment that had been logged about 20 years ago than in one that had been undisturbed for 80 years. The faster processing rate was accompanied by significantly higher leaf pack densities of total macroinvertebrates, shredders, and collector-gatherers. The higher densities of leaf pack macroinvertebrates were apparently a result of differences in tree species between the two catchments. These differences resulted in greater inputs of fast-decomposing leaf litter to the stream draining the disturbed catchment and in smaller amounts of leaf litter remaining in the stream draining the disturbed catchment by spring when this study was conducted. C1 W VIRGINIA UNIV,DIV FORESTRY,MORGANTOWN,WV 26506. RP GRIFFITH, MB (reprint author), US FISH & WILDLIFE SERV,W VIRGINIA COOPERAT FISH & WILDLIFE RES UNIT,MORGANTOWN,WV 26506, USA. NR 32 TC 29 Z9 29 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD AUG 15 PY 1991 VL 220 IS 3 BP 247 EP 254 DI 10.1007/BF00006580 PG 8 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK310 UT WOS:A1991GK31000007 ER PT J AU CRONE, AJ AF CRONE, AJ TI EARTHQUAKES IN ASEISMIC ZONES SO NATURE LA English DT Editorial Material RP CRONE, AJ (reprint author), US GEOL SURVEY,DENVER,CO 80225, USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD AUG 15 PY 1991 VL 352 IS 6336 BP 570 EP 570 DI 10.1038/352570a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA GB211 UT WOS:A1991GB21100027 ER PT J AU PERRIN, M PREVOT, M MANKINEN, EA AF PERRIN, M PREVOT, M MANKINEN, EA TI LOW INTENSITY OF THE GEOMAGNETIC-FIELD IN EARLY JURASSIC TIME SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID THERMOREMANENT MAGNETIZATION; NORTH-AMERICA; AGE; PALEOINTENSITIES; CONNECTICUT; PORTUGAL; FLOWS; ROCKS; SPAIN AB From a large collection of Jurassic continental tholeiites cropping out in Europe and Africa, we selected 90 samples for paleointensity determinations. The samples were carefully selected to avoid any secondary magnetizations, especially viscous magnetization. Use of the Thellier method reveals that magnetic property changes due to heating begin often at quite low temperatures but fortunately without modifying noticeably their natural remanent magnetization-thermoremanent magnetization ratio. Twenty-eight well-clustered paleointensity estimates were obtained from two European dikes that were emplaced during Early Jurassic time: the Kerforne dike at Brenterc'h in Brittany (northwestern France) and the Messeiana dike on the Iberian Peninsula (Spain and Portugal). Virtual dipole moments calculated from both magmatic units are similar and only about one-third of present-day values. These new data lend support to the recently postulated low dipole moment of the Mesozoic geomagnetic field. C1 US GEOL SURVEY,ISOTOPE GEOL BRANCH,MENLO PK,CA 94025. UNIV MONTPELLIER 2,F-34095 MONTPELLIER 5,FRANCE. RP PERRIN, M (reprint author), CNRS,CTR GEOL & GEOPHYS,F-34095 MONTPELLIER 5,FRANCE. NR 37 TC 26 Z9 27 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD AUG 10 PY 1991 VL 96 IS B9 BP 14197 EP 14210 DI 10.1029/91JB00871 PG 14 WC Geosciences, Multidisciplinary SC Geology GA GA407 UT WOS:A1991GA40700001 ER PT J AU SHERMAN, DM AF SHERMAN, DM TI THE HIGH-PRESSURE ELECTRONIC-STRUCTURE OF MAGNESIOWUSTITE (MG, FE)O - APPLICATIONS TO THE PHYSICS AND CHEMISTRY OF THE LOWER MANTLE SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID OPTICAL-ABSORPTION; ELECTRICAL-CONDUCTIVITY; IRON-OXIDES; MGO; EARTH; CORE; METALLIZATION; SPECTRA; STATE; FEO AB The electonic structure of magnesiowustite is investigated using self-consistent field X-alpha scattered wave (SCF-X-alpha-SW) molecular orbital calculations on (FeO6)10- and (FeMg12O14)2- clusters. Calculated one-electron transition energies are used to interpret the optical spectrum of (Mg, Fe)O. The results are applied to the electrical and thermal conductivity of the lower mantle. The spin pairing of Fe2+ and the effect of pressure on bonding in magnesiowustite, with some inferences regarding the incorporation of oxygen in the outer core, is also addressed. The approach used here appears to give a reliable description of the energy and pressure dependence of the spin-allowed 5T2g --> 5E(g) ligand field transition and the spin-pairing transition of Fe2+ in (Mg, Fe)O. However, the oxygen to metal charge transfer transitions in (Mg, Fe)O are not as reliably determined insofar as the p-d band gap varies with cluster size and the energies of the charge transfer states cannot be found without including configurational interaction. Nevertheless, it is argued that the charge transfer transitions that are intrinsic to (Fe, Mg)O are of a sufficiently high energy to be irrelevant to the electrical and thermal conductivity of the lower mantle. This is especially true if Fe2+ adopts the low-spin configuration. The geophysically significant properties of (Fe, Mg)O probably result from defect Fe3+. RP SHERMAN, DM (reprint author), US GEOL SURVEY,DENVER FED CTR,MAIL STOP 964,BOX 25046,DENVER,CO 80225, USA. RI Sherman, David/A-7538-2008 OI Sherman, David/0000-0003-1835-6470 NR 66 TC 41 Z9 42 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD AUG 10 PY 1991 VL 96 IS B9 BP 14299 EP 14312 DI 10.1029/91JB01202 PG 14 WC Geosciences, Multidisciplinary SC Geology GA GA407 UT WOS:A1991GA40700007 ER PT J AU KING, CY AF KING, CY TI MULTICYCLE SLIP DISTRIBUTION ALONG A LABORATORY FAULT SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID CHARACTERISTIC EARTHQUAKES; RECURRENCE; MODEL; PREDICTION; BARRIERS AB Slip distribution along a laboratory fault, which consists of eight spring-connected blocks that are elastically driven to slide on a frictional surface, has been examined for a "long" sequence of slip events to test the applicability of some conceptual models proposed recently in the literature. The distributions of large slip events are found to be quite variable and do not fit the uniform slip or characteristic earthquake models. The rupture initiation points are usually not near the corresponding maximum slip points, in contrast to observations by Thatcher (1990) and by Fukao and Kikuchi (1987) that earthquake hypocenters are commonly near corresponding regions of maximum slip in the fault planes. This contrast may suggest that either the present observations or theirs are not representative or the teleseismically determined hypocenters may not always be true rupture initiation points as usually assumed. Large slip events are also found to be a stress-roughening process. They are triggered by some small events after the stresses have been adjusted by some earlier small-to-moderate events to be near the critical levels at most locations along the fault. This suggests that earthquake prediction monitoring efforts should not be limited to a small region near an asperity but should be spread out to cover the entire fault segment in a seismic gap in order to detect the condition of simultaneous strain buildup. RP KING, CY (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 24 TC 5 Z9 5 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD AUG 10 PY 1991 VL 96 IS B9 BP 14377 EP 14381 DI 10.1029/91JB01313 PG 5 WC Geosciences, Multidisciplinary SC Geology GA GA407 UT WOS:A1991GA40700012 ER PT J AU SAVAGE, JC LISOWSKI, M AF SAVAGE, JC LISOWSKI, M TI STRAIN ACCUMULATION ALONG THE DENALI FAULT AT THE NENANA RIVER AND DELTA RIVER CROSSINGS, ALASKA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID YAKATAGA SEISMIC GAP; SOUTHERN ALASKA; SYSTEM; CALIFORNIA AB Surveys of trilateration networks across the Denali fault at the Nenana River in 1982, 1984, and 1988 and at the Delta River in 1975, 1979, 1982, and 1984 indicate a minor (0.10 +/- 0.04-mu-strain/yr) northeastward uniaxial extension. The component of right-lateral shear-strain accumulation across the fault is not significant at the two-standard-deviation level. At the Delta River network the strain accumulation rate decreases rapidly with distance from the fault, but evidence for a similar decrease with distance from the fault is lacking at the Nenana River network. The strain accumulation rates inferred from trilateration are consistent with the very long baseline interferometry (VLBI) measurement reported by Ma et al. (1990) and support their contention that significant right-lateral shear is not accumulating along the Denali fault at the present time. Savage et al. (1981) had earlier concluded erroneously that preliminary geodetic measurements at the Delta River network demonstrated right-lateral shear strain accumulation. The absence of significant right-lateral deformation across the Denali fault in the 1975-1988 interval is in marked constrast with the abundant geomorphic evidence for Holocene right-lateral secular slip at the rate of 10-20 mm/yr on the Denali fault in this sector. RP SAVAGE, JC (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 19 TC 12 Z9 12 U1 2 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD AUG 10 PY 1991 VL 96 IS B9 BP 14481 EP 14492 DI 10.1029/91JB01285 PG 12 WC Geosciences, Multidisciplinary SC Geology GA GA407 UT WOS:A1991GA40700018 ER PT J AU SAVAGE, JC LISOWSKI, M PRESCOTT, WH AF SAVAGE, JC LISOWSKI, M PRESCOTT, WH TI STRAIN ACCUMULATION IN WESTERN WASHINGTON SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID CASCADIA SUBDUCTION ZONE; MECHANICAL ENERGY BUDGET; DE-FUCA PLATE; SOUTHERN-CALIFORNIA; EARTHQUAKES; DEFORMATION; MODEL; FAULT; MOVEMENTS; BENEATH AB The Juan de Fuca plate is subducted beneath the North American plate off the coast of Washington at a rate of about 40 mm/yr N68-degrees-E. The average principal strain rates (extension reckoned positive) measured in northwestern Washington are as follows: Olympic peninsula 25 km south of Port Angeles from 1982 through 1990, epsilon-1 = 0.011 +/- 0.027-mu-strain/yr N31-degrees-W +/- 6.6-degrees and epsilon-2 = -0.092 +/- 0.028-mu-strain/yr N59-degrees-E +/- 6.6-degrees and near Seattle from 1972 through 1985, epsilon-1 = 0.027 +/- 0.019-mu-strain/yr N22-degrees-W +/- 6.4-degrees and epsilon-2 = -0.036 +/- 0.013-mu-strain/yr N68-degrees-E +/- 6.4-degrees. Both strain measurements are consistent with uniaxial contraction in the direction of plate convergence. Uplift rates inferred from tide gage recordings are about 4 mm/yr on the Pacific coast and near 0 mm/yr farther inland near Seattle. These deformation rates are consistent with a model of the Cascadia subduction zone in which the plate interface beneath the continental slope and outer continental shelf is locked but free to slip farther landward. The limited downdip extent of the locked segment of the plate interface is consistent with a shallow depth (approximately 20 km) of the isotherm (approximately 450-degrees-C) that defines the brittle-ductile transition. Small thrust events diagnostic of seismic subduction should then occur only offshore and at shallow depths. The principal strain rates measured from 1972 through 1983 in the back arc region near Richland, Washington, are epsilon-1 = -0.016 +/- 0.013-mu-strain/yr N03-degrees-W +/- 34-degrees and epsilon-2 = -0.024 +/- 0.013-mu-strain/yr N87-degrees-E +/- 34-degrees. RP SAVAGE, JC (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS-977,MENLO PK,CA 94025, USA. NR 53 TC 66 Z9 66 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD AUG 10 PY 1991 VL 96 IS B9 BP 14493 EP 14507 DI 10.1029/91JB01274 PG 15 WC Geosciences, Multidisciplinary SC Geology GA GA407 UT WOS:A1991GA40700019 ER PT J AU MICHAEL, AJ EBERHARTPHILLIPS, D AF MICHAEL, AJ EBERHARTPHILLIPS, D TI RELATIONS AMONG FAULT BEHAVIOR, SUBSURFACE GEOLOGY, AND 3-DIMENSIONAL VELOCITY MODELS SO SCIENCE LA English DT Article ID SAN-ANDREAS FAULT; 1984 MORGAN HILL; PORE PRESSURE; LOMA-PRIETA; CALIFORNIA; EARTHQUAKE; DEFORMATION; PARKFIELD; SLIP; SEISMICITY AB The development of three-dimensional P-wave velocity models for the regions surrounding five large earthquakes in California has lead to the recognition of relations among fault behavior and the material properties of the rocks that contact the fault at seismogenic depths; regions of high moment release appear to correlate with high seismic velocities whereas rupture initiation or termination may be associated with lower seismic velocities. These relations point toward a physical understanding of why faults are divided into segments that can fail independently, an understanding that could improve our ability to predict earthquakes and strong ground motion. RP MICHAEL, AJ (reprint author), US GEOL SURVEY,SEISMOL BRANCH,MAIL STOP 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. RI Michael, Andrew/A-5059-2010 OI Michael, Andrew/0000-0002-2403-5019 NR 36 TC 102 Z9 102 U1 3 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD AUG 9 PY 1991 VL 253 IS 5020 BP 651 EP 654 DI 10.1126/science.253.5020.651 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA GA304 UT WOS:A1991GA30400035 PM 17772370 ER PT J AU TURRIN, BD CHAMPION, D FLECK, RJ AF TURRIN, BD CHAMPION, D FLECK, RJ TI AR-40/AR-39 AGE OF THE LATHROP-WELLS-VOLCANIC-CENTER, YUCCA MOUNTAIN, NEVADA SO SCIENCE LA English DT Article ID RADIOACTIVE-WASTE REPOSITORY; SOUTHERN NEVADA AB Paleomagnetic and Ar-40/Ar-39 analyses from the Lathrop Wells volcanic center, Nevada, indicate that two eruptive events have occurred there. The ages (136 +/- 8 and 141 +/- 9 thousand years ago) for these two events are analytically indistinguishable. The small angular difference (4.7-degrees) between the paleomagnetic directions from these two events suggests they differ in age by only about 100 years. These ages are consistent with the chronology of the surficial geological units in the Yucca Mountain area. These results contradict earlier interpretations of the cinder-cone geomorphology and soil-profile data that suggest that at least five temporally discrete eruptive events occurred at Lathrop Wells approximately 20,000 years ago. C1 INST HUMAN ORIGINS,CTR GEOCHRONOL,BERKELEY,CA 94709. RP TURRIN, BD (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 23 TC 24 Z9 24 U1 0 U2 3 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD AUG 9 PY 1991 VL 253 IS 5020 BP 654 EP 661 DI 10.1126/science.253.5020.654 PG 8 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA GA304 UT WOS:A1991GA30400036 PM 17772371 ER PT J AU CHAFFEE, MA AF CHAFFEE, MA TI THE INTERNATIONAL DISSEMINATION OF SCIENTIFIC-INFORMATION - THE AEG CONNECTION SO JOURNAL OF GEOCHEMICAL EXPLORATION LA English DT Editorial Material RP CHAFFEE, MA (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 973,DENVER,CO 80225, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-6742 J9 J GEOCHEM EXPLOR JI J. Geochem. Explor. PD AUG 5 PY 1991 VL 40 IS 1-3 BP 1 EP 8 DI 10.1016/0375-6742(91)90028-S PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GE448 UT WOS:A1991GE44800003 ER PT J AU THEOBALD, PK EPPINGER, RG TURNER, RL SHEN, SQ AF THEOBALD, PK EPPINGER, RG TURNER, RL SHEN, SQ TI THE EFFECT OF SCALE ON THE INTERPRETATION OF GEOCHEMICAL ANOMALIES SO JOURNAL OF GEOCHEMICAL EXPLORATION LA English DT Article; Proceedings Paper CT 13TH INTERNATIONAL GEOCHEMICAL EXPLORATION SYMP ( IGES ) / 2ND BRAZILIAN GEOCHEMICAL CONGRESS CY OCT 01-06, 1989 CL RIO DE JANEIRO, BRAZIL SP ASSOC EXPLORAT GEOCHEMISTS, BRAZILIAN GEOCHEM SOC ID MINERALIZATION AB The purpose of geochemical surveys changes with scale. Regional surveys identify areas where mineral deposits are most likely to occur, whereas intermediate surveys identify and prioritize specific targets. At detailed scales specific deposit models may be applied and deposits delineated. The interpretation of regional geochemical surveys must take into account scale-dependent difference in the nature and objectives of this type of survey. Overinterpretation of regional data should be resisted, as should recommendations to restrict intermediate or detailed follow-up surveys to the search for specific deposit types or to a too limited suite of elements. Regional surveys identify metallogenic provinces within which a variety of deposit types and metals are most likely to be found. At intermediate scale, these regional provinces often dissipate into discrete clusters of anomalous areas. At detailed scale, individual anomalous areas reflect local conditions of mineralization and may seem unrelated to each other. Four examples from arid environments illustrate the dramatic change in patterns of anomalies between regional and more detailed surveys. On the Arabian Shield, a broad regional anomaly reflects the distribution of highly differentiated anorogenic granites. A particularly prominent part of the regional anomaly includes, in addition to the usual elements related to the granites, the assemblage of Mo, W and Sn. Initial interpretation suggested potential for granite-related, stockwork Mo deposits. Detailed work identified three separate sources for the anomaly: a metal-rich granite, a silicified and stockwork-veined area with scheelite and molybdenite, and scheelite/powellite concentrations in skarn deposits adjacent to a ring-dike complex. Regional geochemical, geophysical and remote-sensing data in the Sonoran Desert, Mexico, define a series of linear features interpreted to reflect fundamental, northeast-trending fractures in the crust that served as the prime conduits for mineralizing fluids. At a larger scale, the linear, northeast-trending anomalies can be shown to result from a series of discrete mineralized systems with different ages and mineral assemblages. The linear pattern of anomalies disintegrates. A regional geochemical survey in the Sonoran Desert in southwestern Arizona displays a cluster of samples anomalous in Pb, Mo, Bi and W. In detail, the original regional anomaly separates into four discrete anomalous areas, each with its own distinctive suite of elements, geographic distribution and age of mineralization. A prominent regional gold anomaly in the Gobi Desert, Xinjiang, Peoples Republic of China, extends southeastward for 30 km from known lode gold deposits. Because the anomaly cuts both lithologic units and the structural grain, and because it parallels the prevailing direction of high-velocity winds, it was originally attributed to eolian dispersion. In detail, the regional anomaly consists of several east-west-trending anomalies, parallel to local lithology and structure that most likely reflect independent sources of lode gold. The regional anomaly results from smoothing of an en-echelon set of local anomalies. These examples emphasize that interpretation of regional anomalies must be tempered to consider regional-sized geologic features. Attempts to overinterpret anomalies by assigning deposit-scale attributes to regional anomalies can lead to confusion and incorrect interpretations. Potential targets that can be readily resolved only at intermediate or detailed scales of study may be overlooked. C1 UNIV NEVADA,MACKAY SCH MINES,US GEOL SURVEY,RENO,NV 89557. MINIST GEOL & MINERAL RESOURCES,BEIJING,PEOPLES R CHINA. RP THEOBALD, PK (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,MS 973,DENVER,CO 80225, USA. NR 13 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-6742 J9 J GEOCHEM EXPLOR JI J. Geochem. Explor. PD AUG 5 PY 1991 VL 40 IS 1-3 BP 9 EP 23 DI 10.1016/0375-6742(91)90029-T PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GE448 UT WOS:A1991GE44800004 ER PT J AU DEVIVO, B AYUSO, RA BELKIN, HE LIMA, A MESSINA, A VISCARDI, A AF DEVIVO, B AYUSO, RA BELKIN, HE LIMA, A MESSINA, A VISCARDI, A TI ROCK CHEMISTRY AND FLUID INCLUSION STUDIES AS EXPLORATION TOOLS FOR ORE-DEPOSITS IN THE SILA BATHOLITH, SOUTHERN ITALY SO JOURNAL OF GEOCHEMICAL EXPLORATION LA English DT Article; Proceedings Paper CT 13TH INTERNATIONAL GEOCHEMICAL EXPLORATION SYMP ( IGES ) / 2ND BRAZILIAN GEOCHEMICAL CONGRESS CY OCT 01-06, 1989 CL RIO DE JANEIRO, BRAZIL SP ASSOC EXPLORAT GEOCHEMISTS, BRAZILIAN GEOCHEM SOC AB The Sila batholith is the focus of an extensive petrogenetic research program, which includes an assessment of its potential to host granite-related ore deposits. Univariate and multivariate statistical techniques were applied to major- and minor-element rock geochemical data. The analysis indicates that the highest potential for mineralization occurs in corundum-normative, peraluminous, unfoliated, relatively late-stage plutons. The plutons are enriched in Rb, Nb, Ta and U, but depleted in Fe, Mg and Sr. The K/Rb, Ba/Rb, Rb/Sr and Rb3/Ba.Sr.K indices and high R-factor scores of Si-K-Rb are typical of mineralized granitic rocks. A reconnaissance fluid inclusion study indicates that the sub-solidus rock was infiltrated by solutions of widely different temperatures (50-416-degrees-C) and variable salinites (0 to approximately 26 wt.% NaCl equivalent). The higher-temperature solutions probably represent granite or magmatic-related Hercynian fluids, whereas the lower-temperature fluids may be either Hercynian or Alpine in age. Fluids with characteristics typical of mineralized "porphyry" systems have not been recognized. C1 US GEOL SURVEY,RESTON,VA 22092. INST SCI TERRA,I-98166 MESSINA,ITALY. RP DEVIVO, B (reprint author), DIPARTIMENTO GEOFIS & VULCANOL,LARGO S MARCELLINO 10,I-80138 NAPLES,ITALY. OI Belkin, Harvey/0000-0001-7879-6529 NR 20 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-6742 J9 J GEOCHEM EXPLOR JI J. Geochem. Explor. PD AUG 5 PY 1991 VL 40 IS 1-3 BP 291 EP 310 DI 10.1016/0375-6742(91)90044-U PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GE448 UT WOS:A1991GE44800019 ER PT J AU SCOTT, KM RABONE, G CHAFFEE, MA AF SCOTT, KM RABONE, G CHAFFEE, MA TI WEATHERING AND ITS EFFECT UPON GEOCHEMICAL DISPERSION AT THE POLYMETALLIC WAGGA TANK DEPOSIT, NSW, AUSTRALIA SO JOURNAL OF GEOCHEMICAL EXPLORATION LA English DT Article; Proceedings Paper CT 13TH INTERNATIONAL GEOCHEMICAL EXPLORATION SYMP ( IGES ) / 2ND BRAZILIAN GEOCHEMICAL CONGRESS CY OCT 01-06, 1989 CL RIO DE JANEIRO, BRAZIL SP ASSOC EXPLORAT GEOCHEMISTS, BRAZILIAN GEOCHEM SOC ID NEW-SOUTH-WALES; COBAR AB The Wagga Tank Zn-Pb-Cu-Ag-Au deposit comprises multiple, steeply dipping and structurally controlled sulfide lodes within Early Devonian turbidites and volcaniclastics. Complete weathering at the prospect extends to 100 m below the current land surface. Detailed geochemical studies of drill-derived regolith material were supplemented by extensive mineralogical investigations and enable the major features of the weathered profile to be delineated. The profile consists of soil with reworked portions of a ferruginous lateritic capping within a largely transported overburden. Below the soil, some residual ferruginous capping (characterized by maghemite) occurs above a kaolinite-rich zone which passes into goethitic saprolite containing alunite-jarosite family minerals. This lateritic profile was developed during the Tertiary period prior to the Late Miocene onset of more arid conditions. Within the goethitic saprolite, Pb and some Au have remained in their Miocene positions. However, the distributions of Cu and Zn largely reflect the effect of post-Miocene aridity. Thus, these elements (and some Au) are concentrated as supergene minerals at the current water table, with isolated zones higher in the weathered profile reflecting former levels of the water table. Preferential sampling of ferruginous lateritic material in the overlying transported soil can enhance geochemical anomalies and indicate the presence of concealed mineralization at Wagga Tank. C1 HOMESTAKE AUSTRALIA LTD,NORWOOD,SA 5067,AUSTRALIA. US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. RP SCOTT, KM (reprint author), CSIRO,DIV EXPLORAT GEOSCI,POB 136,N RYDE,NSW 2113,AUSTRALIA. NR 9 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-6742 J9 J GEOCHEM EXPLOR JI J. Geochem. Explor. PD AUG 5 PY 1991 VL 40 IS 1-3 BP 413 EP 426 DI 10.1016/0375-6742(91)90050-5 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GE448 UT WOS:A1991GE44800025 ER PT J AU CECIL, CB EDGAR, NT AF CECIL, CB EDGAR, NT TI PALEOCLIMATE CONTROLS ON THE ORIGIN OF SOME BLACK SHALES IN PALEOZOIC EPEIRIC SEAS OF THE EASTERN UNITED-STATES SO AAPG BULLETIN LA English DT Meeting Abstract C1 US GEOL SURVEY, RESTON, VA 22092 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC PETROLEUM GEOLOGIST PI TULSA PA 1444 S BOULDER AVE, PO BOX 979, TULSA, OK 74119-3604 USA SN 0149-1423 J9 AAPG BULL JI AAPG Bull. PD AUG PY 1991 VL 75 IS 8 BP 1380 EP 1381 PG 2 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500015 ER PT J AU CECIL, CB DULONG, FT FEDORKO, N AF CECIL, CB DULONG, FT FEDORKO, N TI LATE PENNSYLVANIAN PALEOCLIMATE CYCLES, SEDIMENT FLUX, AND ORGANIC PRODUCTIVITY IN THE APPALACHIAN BASIN SO AAPG BULLETIN LA English DT Meeting Abstract C1 W VIRGINIA GEOL & ECON SURVEY, MORGANTOWN, WV USA. US GEOL SURVEY, RESTON, VA 22092 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER ASSOC PETROLEUM GEOLOGIST PI TULSA PA 1444 S BOULDER AVE, PO BOX 979, TULSA, OK 74119-3604 USA SN 0149-1423 J9 AAPG BULL JI AAPG Bull. PD AUG PY 1991 VL 75 IS 8 BP 1380 EP 1380 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500014 ER PT J AU LYONS, PC HACQUEBARD, PA OUTERBRIDGE, WF AF LYONS, PC HACQUEBARD, PA OUTERBRIDGE, WF TI EVIDENCE OF CARBONIFEROUS VOLCANIC ASH IN PICTOU GROUP (WEST-PHALIAN-D), SYDNEY COALFIELD, NOVA-SCOTIA, CANADA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. ATLANTIC GEOSCI CTR,DARTMOUTH,NS,CANADA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1387 EP 1387 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500044 ER PT J AU MILLER, BM AF MILLER, BM TI AN OBJECT-ORIENTED EXPERT SYSTEM FOR SEDIMENTARY BASIN ANALYSIS SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1388 EP 1388 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500048 ER PT J AU ROEN, JB RYDER, RT DEWITT, W AF ROEN, JB RYDER, RT DEWITT, W TI ATLAS OF APPALACHIAN BASIN OIL AND GAS PLAYS - THE ORISKANY SANDSTONE PLAY - A PRELIMINARY EXAMPLE SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1390 EP 1390 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500057 ER PT J AU RYDER, RT BURRUSS, RC HATCH, JR AF RYDER, RT BURRUSS, RC HATCH, JR TI GEOCHEMISTRY AND ORIGIN OF OIL FROM CAMBRIAN AND ORDOVICIAN RESERVOIRS IN EASTERN AND CENTRAL OHIO SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1390 EP 1390 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500059 ER PT J AU COOK, HE GATOSVSEEY, YA PONOEEARENKO, SB STYEHTSYEHNKA, IV STYEHTSYENNKA, VP ZHEMCHUZHNIKOV, V ZORAN, AE AF COOK, HE GATOSVSEEY, YA PONOEEARENKO, SB STYEHTSYEHNKA, IV STYEHTSYENNKA, VP ZHEMCHUZHNIKOV, V ZORAN, AE TI CARBONATE PLATFORM EVOLUTION, UPPER PALEOZOIC, SOUTHERN KAZAKHSTAN, USSR - A SURFACE ANALOG FOR THE SUPER GIANT TENGIZ OIL-FIELD, WESTERN KAZAKHSTAN SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,MENLO PK,CA 94025. ACAD SCI KASSR,INST GEOL SCI,ALMA ATA 480021,KAZAKHSTAN,USSR. MINIST GEOL ALMA ATA,ALMA ATA,KAZAKHSTAN,USSR. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1408 EP 1408 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500135 ER PT J AU GAUTIER, DL SHENK, CJ MAST, RF AF GAUTIER, DL SHENK, CJ MAST, RF TI GEOLOGIC CONSTRAINTS ON OIL-RECOVERY AND UNCERTAINTIES IN UNDISCOVERED RESOURCES SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1411 EP 1411 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500145 ER PT J AU MASSON, DG HUGGETT, QJ WEAVER, PPE KIDD, RB GARDNER, JV AF MASSON, DG HUGGETT, QJ WEAVER, PPE KIDD, RB GARDNER, JV TI QUATERNARY SEDIMENTARY PROCESSES ON THE NORTHWESTERN AFRICAN CONTINENTAL-MARGIN - AN INTEGRATED STUDY USING SIDE-SCAN SONAR, HIGH-RESOLUTION PROFILING, AND CORE DATA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 INST OCEANOG SCI,WORMLEY,SURREY,ENGLAND. UNIV WALES COLL CARDIFF,CARDIFF CF1 1XL,S GLAM,WALES. US GEOL SURVEY,MENLO PK,CA 94025. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1416 EP 1416 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500166 ER PT J AU MASTERS, CD AF MASTERS, CD TI GLOBAL RESOURCES AND PREDICTION SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1416 EP 1416 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500167 ER PT J AU ULMISHEK, GF AF ULMISHEK, GF TI STRUCTURAL EVOLUTION AND PETROLEUM PRODUCTIVITY OF THE BALTIC BASIN SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD AUG PY 1991 VL 75 IS 8 BP 1423 EP 1423 PG 1 WC Geosciences, Multidisciplinary SC Geology GA GA885 UT WOS:A1991GA88500192 ER PT J AU SPARLING, DW AF SPARLING, DW TI ACID PRECIPITATION AND FOOD QUALITY - EFFECTS OF DIETARY AL, CA, AND P ON BONE AND LIVER CHARACTERISTICS IN AMERICAN BLACK DUCKS AND MALLARDS SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID LAYING HENS; STREPTOPELIA-RISORIA; ALUMINUM; PHOSPHORUS; CALCIUM; ACIDIFICATION; PERFORMANCE; METABOLISM; SURVIVAL; GROWTH AB American black ducks (Anas rubripes) and mallards (A. platyrhynchos) were fed diets varying in concentrations of aluminum (Al), calcium (Ca), and phosphorus (P) for 10 weeks to identify toxic effects of Al under conditions representative of areas with acid precipitation. Femur and liver tissues were analyzed for Al, Ca, and P concentrations and structural characteristics. At two weeks of age, both species demonstrated pronounced differences in femur Al and P concentrations and femur mass from dietary Al and interaction between Ca:P regimen and Al; Low Ca:Low P enhanced Al storage and decreased P and mass in femurs. Femur Ca was lowest in the Low Ca:Low P regimen but was not affected by dietary Al. At 10 weeks, femur and liver Al continued to vary with dietary Al. Elevated Al and reduced Ca lowered modulus of elasticity. Femur P increased with elevated dietary P in black ducks. Elevated dietary P negated some of the effects of dietary Al on femur mass in black ducks. Reduced Ca concentrations weakened bones of both species and lowered both Ca and P. An array of clinical signs including lameness, discoloration of the upper mandible, complete and greenstick fractures, and death were responses to elevated Al and Ca:P regimen. Black ducks seemed to display these signs over a wider range of diets than mallards. Diets of 1,000 mg/kg Al had toxic effects on both species, particularly when combined with diets low in Ca and P. RP SPARLING, DW (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 30 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD AUG PY 1991 VL 21 IS 2 BP 281 EP 288 PG 8 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FW794 UT WOS:A1991FW79400016 ER PT J AU WINGER, PV LASIER, PJ AF WINGER, PV LASIER, PJ TI A VACUUM-OPERATED PORE-WATER EXTRACTOR FOR ESTUARINE AND FRESH-WATER SEDIMENTS SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID SAMPLER; BIOAVAILABILITY; QUALITY; METALS AB A vacuum-operated pore-water extractor for estuarine and freshwater sediments was developed and constructed from a fused-glass air stone attached with aquarium airline tubing to a 30 or 60 cc polypropylene syringe. Pore water is extracted by inserting the air stone into the sediment and creating a vacuum by retracting and bracing the syringe plunger. A hand-operated vacuum pump attached to a filtration flask was also evaluated as an alternative vacuum source. The volume and time to extract pore water varies with the number of devices and the sediment particle size. Extraction time is longer for fine sediments than for sandy sediments. Four liters of sediment generally yield between 500 and 1,500 mL of pore water. The sediment that surrounds and accumulates on the air stone acts as a filter, and, except for the first few milliliters, the collected pore water is clear. Because there is no exposure to air or avenue for escape, volatile compounds and in situ characteristics are retained in the extracted pore water. RP WINGER, PV (reprint author), UNIV GEORGIA,SCH FOREST RESOURCES,US FISH & WILDLIFE SERV,ATHENS,GA 30602, USA. NR 43 TC 39 Z9 40 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD AUG PY 1991 VL 21 IS 2 BP 321 EP 324 PG 4 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FW794 UT WOS:A1991FW79400022 ER PT J AU CARRARA, PE TRIMBLE, DA RUBIN, M AF CARRARA, PE TRIMBLE, DA RUBIN, M TI HOLOCENE TREELINE FLUCTUATIONS IN THE NORTHERN SAN-JUAN MOUNTAINS, COLORADO, USA, AS INDICATED BY RADIOCARBON-DATED CONIFER WOOD SO ARCTIC AND ALPINE RESEARCH LA English DT Article ID SOUTHWESTERN UNITED-STATES; MARITIME TROPICAL AIR; JASPER-NATIONAL-PARK; TIMBERLINE; GULF; CALIFORNIA; ALBERTA; RANGE AB An early to mid-Holocene warm period with greater than present-day monsoonal circulation is indicated by evidence in the northern San Juan Mountains of southwestern Colorado. Fifty radiocarbon ages of coniferous wood fragments, and several other radiocarbon ages of willow fragments, woody peat, and organic sediment associated with conifer remains, recovered from six sites at or above present-day treeline indicate that during the first half of the Holocene treeline was higher than present. Radiocarbon ages of coniferous wood fragments recovered from the remains of Lake Emma, a former glacial tarn above present-day treeline, indicate that between 9600 and 5400 BP treeline in the northern San Juan Mountains was at least 80 m higher than present. Furthermore, a radiocarbon age of a large spruce fragment with a complacent annual-ring record suggests that at about 8000 BP timberline may have been at least 140 m higher than present. These data suggest that during the early to mid-Holocene average July temperatures were at least 0.5 to 0.9-degrees-C higher than present. Radiocarbon ages and stratigraphy from bogs in the study area near present-day treeline suggest that between 5400 and 3500 BP treeline was near its present-day limits. After 3500 BP treeline was generally lower than present although short climatic ameliorations, with accompanying rises in treeline, may have occurred at about 3100 and 2400 BP. Deuterium concentrations previously determined for the cellulose of 18 conifer fragments from the Lake Emma site indicate a 70-parts-per-thousand decrease in deuterium from 9600 BP to present. These data indicate that the early Holocene increase in July solar radiation may have resulted in the intensification of the Arizona monsoon at that time. C1 US GEOL SURVEY,MENLO PK,CA 94025. US GEOL SURVEY,NATL CTR,RESTON,VA 22092. RP CARRARA, PE (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 913,DENVER,CO 80225, USA. NR 32 TC 50 Z9 50 U1 0 U2 5 PU INST ARCTIC ALPINE RES PI BOULDER PA UNIV COLORADO, BOULDER, CO 80309 SN 0004-0851 J9 ARCTIC ALPINE RES JI Arct. Alp. Res. PD AUG PY 1991 VL 23 IS 3 BP 233 EP 246 DI 10.2307/1551601 PG 14 WC Environmental Sciences; Geography SC Environmental Sciences & Ecology; Geography GA GD351 UT WOS:A1991GD35100001 ER PT J AU JOYNER, WB AF JOYNER, WB TI DIRECTIVITY FOR NONUNIFORM RUPTURES SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Note ID EARTHQUAKES; SPECTRA RP JOYNER, WB (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 12 TC 24 Z9 25 U1 0 U2 0 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD AUG PY 1991 VL 81 IS 4 BP 1391 EP 1395 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FZ501 UT WOS:A1991FZ50100021 ER PT J AU GRIFFITHS, RW SCHLOESSER, DW LEACH, JH KOVALAK, WP AF GRIFFITHS, RW SCHLOESSER, DW LEACH, JH KOVALAK, WP TI DISTRIBUTION AND DISPERSAL OF THE ZEBRA MUSSEL (DREISSENA-POLYMORPHA) IN THE GREAT-LAKES REGION SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID UNIONIDAE; ABUNDANCE; BIVALVIA; HURON; PALL AB Dreissena polymorpha (Pallas), a small mussel common throughout most of Europe, was discovered in June of 1988 in the southern part of Lake St. Clair. Length-frequency analyses of populations from the Great Lakes and review of historical benthic studies suggest that the mussel was introduced into Lake St. Clair in late 1986, probably as a result of the discharge of ballast water from an ocean-crossing vessel. Following the 1990 reproductive season, Dreissena populations ranged from the head of the St. Clair River, through Lake St. Clair, the Detroit River, Lake Erie, the Welland Canal, and the Niagara River to the western basin and southern shoreline of Lake Ontario. Isolated populations were found in the St. Lawrence River and in harbours in Lakes Huron, Michigan, and Superior. The rapid dispersal of this organism has resulted from its high fecundity, pelagic larval stage, bysso-pelagic drifting ability of juveniles, and human activities associated with commercial shipping, fishing, and boating (research and pleasure). Virtually any waterbody that can be reached by boaters and fisherman within a few days travel of the lower Great Lakes, particularly Lake Erie, seems to be at risk of being invaded by this nuisance species. C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,ANN ARBOR,MI 48105. MINIST NAT RESOURCES,LAKE ERIE FISHERIES STN,WHEATLEY N0P 2P0,ONTARIO,CANADA. DETROIT EDISON CO,DETROIT,MI 48226. RP GRIFFITHS, RW (reprint author), MINIST ENVIRONM,WATER RESOURCES ASSESSMENT UNIT,985 ADELAIDE ST,S LONDON N6E 1V3,ONTARIO,CANADA. NR 56 TC 241 Z9 250 U1 11 U2 113 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD AUG PY 1991 VL 48 IS 8 BP 1381 EP 1388 DI 10.1139/f91-165 PG 8 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA GC707 UT WOS:A1991GC70700005 ER PT J AU JOHANNSSON, OE MILLS, EL OGORMAN, R AF JOHANNSSON, OE MILLS, EL OGORMAN, R TI CHANGES IN THE NEARSHORE AND OFFSHORE ZOOPLANKTON COMMUNITIES IN LAKE-ONTARIO - 1981-88 SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID LAWRENCE GREAT-LAKES; BYTHOTREPHES-CEDERSTROEMI; SEASONAL SUCCESSION; SOUTHSHORE STATIONS; MYSIS-RELICTA; MICHIGAN; DYNAMICS; FISH; POPULATIONS; NORTHSHORE AB We examined trends and factors influencing changes in nearshore and offshore zooplankton abundance and composition in Lake Ontario between 1981 and 1988. In the nearshore (southshore and eastern basin), zooplankton abundance decreased and shifts occurred in the relative abundances of Bosmina longirostris and Daphnia retrocurva (eastern basin) and Daphnia retrocurva and Daphnia galeata mendotae (southshore). These changes could have resulted from increased vertebrate predation or reduced food resources which intensified the effects of predation. In the offshore, the first appearance (FA) of the larger, less common cladoceran species occurred earlier in the season as of 1985. FA was correlated with cumulative epilimnetic temperature (CET) and the catch per unit effort (CPUE) of alewife (Alosa pseudoharengus) greater-than-or-equal-to 165 mm caught in U.S. waters in the spring. In 1987, when CET was high and CPUE of alewife greater-than-or-equal-to 165 mm was low, large populations of these cladocerans developed in June and July. Bythotrephes cederstroemi, a recent invader in the Great Lakes, was abundant only in 1987 when the CPUE of alewife was lowest. Changes in zooplankton abundance, development, and composition along the nearshore-offshore gradient reflected effects of temperature, habitat, and planktivory on the community. C1 CORNELL UNIV,BIOL FIELD STN,BRIDGEPORT,NY 13030. US FISH & WILDLIFE SERV,OSWEGO BIOL STN,OSWEGO,NY 13126. RP JOHANNSSON, OE (reprint author), FISHERIES & OCEANS CANADA,CANADA CTR INLAND WATERS,GREAT LAKES LAB FISHERIES & AQUAT SCI,BURLINGTON L7R 4A6,ONTARIO,CANADA. NR 50 TC 82 Z9 84 U1 0 U2 8 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD AUG PY 1991 VL 48 IS 8 BP 1546 EP 1557 DI 10.1139/f91-183 PG 12 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA GC707 UT WOS:A1991GC70700023 ER PT J AU STEINGRAEBER, MT GINGERICH, WH AF STEINGRAEBER, MT GINGERICH, WH TI HATCHING, GROWTH, ION ACCUMULATION, AND SKELETAL OSSIFICATION OF BROOK TROUT (SALVELINUS-FONTINALIS) ALEVINS IN ACIDIC SOFT WATERS SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID SUCKER CATOSTOMUS-COMMERSONI; LOW ENVIRONMENTAL PH; SALMON SALMO-SALAR; WHOLE-BODY IONS; ATLANTIC SALMON; RAINBOW-TROUT; BROWN TROUT; AMBIENT PH; YOLK-SAC; SWIM-UP AB Brook trout eyed eggs and subsequent alevins were exposed to pH 5.0, 6.5, and 7.0 in soft reconstituted water and to pH 8.2 in hard well water for up to 72 d. Hatching was delayed and hatching success reduced (p < 0.05) in eyed eggs exposed to pH 5.0 and 6.5. Alevin growth was not affected. Fish in all treatments rapidly accumulated monovalent ions in a similar pattern and in the order of Na+ > K+ > Cl- during yolk absorption and early exogenous feeding. Whole-body monovalent ion concentrations were reduced for short periods during yolk absorption in alevins exposed to pH 6.5 and throughout most of the experiment for those exposed to pH 5.0. Whole-body Mg2+ concentrations were not affected by treatment pH and remained near their median hatch level throughout the exposure. The whole-body concentration of Ca2+ was reduced in fish exposed to pH 5.0, particularly near the end of the experiment. Calcium accumulation in fish was influenced by the interaction of pH and time at pH 5.0 but not at the other pH levels. Alevins exposed to pH 5.0 experienced delayed ossification of skeletal structures associated with feeding, respiration, and locomotion that usually persisted for up to 10 d. The detection of skeletal abnormalities early in life might aid in identifying fish populations at risk in acidified waters. C1 UNIV WISCONSIN,DEPT BIOL & MICROBIOL,LA CROSSE,WI 54601. RP STEINGRAEBER, MT (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,FIELD RES STN,POB 936,LA CROSSE,WI 54602, USA. RI Perez , Claudio Alejandro/F-8310-2010 OI Perez , Claudio Alejandro/0000-0001-9688-184X NR 57 TC 12 Z9 13 U1 0 U2 2 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD AUG PY 1991 VL 69 IS 8 BP 2266 EP 2276 DI 10.1139/z91-317 PG 11 WC Zoology SC Zoology GA GR973 UT WOS:A1991GR97300036 ER PT J AU ROBIE, RA HEMINGWAY, BS AF ROBIE, RA HEMINGWAY, BS TI HEAT-CAPACITIES OF KAOLINITE FROM 7-K TO 380-K AND OF DMSO-INTERCALATED KAOLINITE FROM 20-K TO 310-K - THE ENTROPY OF KAOLINITE AL2SI2O5(OH)4 SO CLAYS AND CLAY MINERALS LA English DT Article DE KAOLINITE; HEAT CAPACITY; ENTROPY; SPECIFIC HEAT; DMSO, KAOLINITE ID THERMODYNAMIC PROPERTIES; DIMETHYL SULFOXIDE AB The heat capacities of kaolinite (7 to 380 K) and of dimethyl sulfoxide (DMSO) intercalated kaolinite (20 to 310 K) were measured by adiabatically shielded calorimetry. The third law entropy of kaolinite, S298-degrees, is 200.9 +/- 0.5 J.mol-1.K-1. The "melting point" of the DMSO in the intercalate, 288.0 +/- 0.2 K, is 3.7 K lower than that of pure DMSO, 291.67 K. The heat capacity of DMSO in the intercalate above 290 K is approximately 5.2 J.mol-1.K-1 smaller than that of pure liquid DMSO at the same temperature. RP ROBIE, RA (reprint author), US GEOL SURVEY,NATL CTR,MS 959,RESTON,VA 22092, USA. NR 18 TC 30 Z9 30 U1 2 U2 2 PU CLAY MINERALS SOCIETY PI BOULDER PA PO BOX 4416, BOULDER, CO 80306 SN 0009-8604 J9 CLAY CLAY MINER JI Clay Clay Min. PD AUG PY 1991 VL 39 IS 4 BP 362 EP 368 DI 10.1346/CCMN.1991.0390404 PG 7 WC Chemistry, Physical; Geosciences, Multidisciplinary; Mineralogy; Soil Science SC Chemistry; Geology; Mineralogy; Agriculture GA GG365 UT WOS:A1991GG36500004 ER PT J AU BAYER, RD LOWE, RW LOEFFEL, RE AF BAYER, RD LOWE, RW LOEFFEL, RE TI PERSISTENT SUMMER MORTALITIES OF COMMON MURRES ALONG THE OREGON CENTRAL COAST SO CONDOR LA English DT Article DE COMMON MURRE; URIA-AALGE; BEACHED BIRDS; WING LENGTH; EL-NINO; CULMEN LENGTH; BILL DEPTH ID GUILLEMOTS URIA-AALGE; EL-NINO; PERIOD AB Common Murres (Uria aalge) were found dead on Oregon central coast beaches every July-September from 1978 through 1990, but the magnitude of the mortality varied yearly. Many more hatching-year (HY) than after-hatching-year (AHY) murres usually were found dead. In some years, most HY murre mortalities happened shortly after HY murres had departed their natal colony, but, in other years, most mortalities occurred after HY murres had been at sea for some time and had grown substantially. These summer mortalities are not a recent phenomenon and, in spite of these mortalities, the total number of AHY murres censused at 15 Oregon colonies did not decrease between 1979 and 1988. Shooting, oiling, or entanglement in fishing gear appeared to cause few HY mortalities. The greatest number of beached HY murres occurred just before the 1982-1983 El Nino, and the fewest were found in 1983 during the El Nino. C1 US FISH & WILDLIFE SERV,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365. RP BAYER, RD (reprint author), OREGON STATE UNIV,HATFIELD MARINE SCI,NEWPORT,OR 97365, USA. NR 45 TC 8 Z9 8 U1 0 U2 2 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD AUG PY 1991 VL 93 IS 3 BP 516 EP 525 DI 10.2307/1368183 PG 10 WC Ornithology SC Zoology GA GG626 UT WOS:A1991GG62600005 ER PT J AU GESSAMAN, JA WORKMAN, GW FULLER, MR AF GESSAMAN, JA WORKMAN, GW FULLER, MR TI FLIGHT PERFORMANCE, ENERGETICS AND WATER TURNOVER OF TIPPLER PIGEONS WITH A HARNESS AND DORSAL LOAD SO CONDOR LA English DT Article DE CO2 PRODUCTION; DOUBLY-LABELED WATER METHOD; FLIGHT ENERGY METABOLISM; RADIO TRANSMITTER; TIPPLER PIGEONS; WATER FLUX; FLIGHT DURATION ID POTENTIAL ERRORS; ANIMALS AB We measured carbon dioxide production and water efflux of 12 tippler pigeons (Columba spp.) during seven experimental flights using the doubly labeled water (DLW) method. Prior to the experiment birds were randomly assigned to one of two groups. One group flew as controls (no load or harness) on all seven flights. The other group wore a harness on two flights, a dorsal load/harness package (weighing about 5% of a bird's mass) on two flights, and they were without a load in three flights. Flight duration of pigeons with only a harness and with a dorsal load/harness package was 21 and 26% less, respectively, than the controls. Pigeons wearing a harness, or wearing a dorsal load/harness package lost water 50-90%, and 57-100% faster, respectively, than control pigeons. The mean CO2 production of pigeons wearing a harness or a load/harness package was not significantly different than pigeons without a harness or load. The small sample sizes and large variability in DLW measurements precluded a good test of the energetic cost of flying with a harness and dorsal load. C1 UTAH STATE UNIV,CTR ECOL,LOGAN,UT 84322. UTAH STATE UNIV,DEPT FISHERIES & WILDLIFE,LOGAN,UT 84322. US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. RP GESSAMAN, JA (reprint author), UTAH STATE UNIV,DEPT BIOL,LOGAN,UT 84322, USA. NR 16 TC 30 Z9 30 U1 2 U2 6 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD AUG PY 1991 VL 93 IS 3 BP 546 EP 554 DI 10.2307/1368186 PG 9 WC Ornithology SC Zoology GA GG626 UT WOS:A1991GG62600008 ER PT J AU EULISS, NH JARVIS, RL GILMER, DS AF EULISS, NH JARVIS, RL GILMER, DS TI FEEDING ECOLOGY OF WATERFOWL WINTERING ON EVAPORATION PONDS IN CALIFORNIA SO CONDOR LA English DT Article DE AQUATIC INVERTEBRATES; EVAPORATION PONDS; FEEDING ECOLOGY; NORTHERN PINTAILS; NORTHERN SHOVELERS; RUDDY DUCKS ID FOOD-HABITS; WINGED TEAL; INVERTEBRATES; PINTAILS; WETLANDS; VALLEY; DUCKS AB We examined the feeding ecology of Northern Pintails (Anas acuta), Northern Shovelers (A. clypeata), and Ruddy Ducks (Oxyura jamaicensis) wintering on drainwater evaporation ponds in California from 1982 through 1984. Pintails primarily consumed midges (Chironomidae) (39.3%) and widegeongrass (Ruppia maritima) nutlets (34.6%). Shovelers and Ruddy Ducks consumed 92.5% and 90.1% animal matter, respectively. Water boatmen (Corixidae) (51.6%), rotifers (Rotatoria) (20.4%), and copepods (Copepoda) (15.2%) were the most important Shoveler foods, and midges (49.7%) and water boatmen (36.0%) were the most important foods of Ruddy Ducks. All three species were opportunistic foragers, shifting their diets seasonally to the most abundant foods given their behavioral and morphological attributes. C1 OREGON STATE UNIV,DEPT FISHERIES & WILDLIFE,CORVALLIS,OR 97331. US FISH & WILDLIFE SERV,NO PRAIRIE WILDLIFE RES CTR,DIXON,CA 95620. NR 37 TC 35 Z9 36 U1 3 U2 10 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD AUG PY 1991 VL 93 IS 3 BP 582 EP 590 DI 10.2307/1368190 PG 9 WC Ornithology SC Zoology GA GG626 UT WOS:A1991GG62600012 ER PT J AU HAYWARD, GD KEPLER, CB SCOTT, JM AF HAYWARD, GD KEPLER, CB SCOTT, JM TI POINT COUNTS FROM CLUSTERED POPULATIONS - LESSONS FROM AN EXPERIMENT WITH HAWAIIAN CROWS SO CONDOR LA English DT Article DE POINT COUNTS; CENSUS TECHNIQUES; OBSERVER VARIATION; FLOCK SIZE; HAWAIIAN CROW; ALALA ID SINGING BIRD SURVEYS AB We designed an experiment to identify factors contributing most to error in counts of Hawaiian Crow or Alala (Corvus hawaiiensis) groups that are detected aurally. Seven observers failed to detect calling Alala on 197 of 361 3-min point counts on four transects extending from cages with captive Alala. A detection curve describing the relation between frequency of flock detection and distance typified the distribution expected in transect or point counts. Failure to detect calling Alala was affected most by distance, observer, and Alala calling frequency. The number of individual Alala calling was not important in detection rate. Estimates of the number of Alala calling (flock size) were biased and imprecise: average difference between number of Alala calling and number heard was 3.24 (+/- 0.277). Distance, observer, number of Alala calling, and Alala calling frequency all contributed to errors in estimates of group size (P < 0.0001). Multiple regression suggested that number of Alala calling contributed most to errors. These results suggest that well-designed point counts may be used to estimate the number of Alala flocks but cast doubt on attempts to estimate flock size when individuals are counted aurally. C1 UNIV IDAHO,DEPT FISH & WILDLIFE RESOURCES,MOSCOW,ID 83848. UNIV GEORGIA,SCH FOREST RESOURCES,US FISH & WILDLIFE SERV,SE RES GRP,ATHENS,GA 30602. UNIV IDAHO,DEPT FISH & WILDLIFE RESOURCES,US FISH & WILDLIFE SERV,MOSCOW,ID 83843. RP HAYWARD, GD (reprint author), COLORADO STATE UNIV,DEPT ZOOL,FT COLLINS,CO 80523, USA. NR 15 TC 3 Z9 3 U1 2 U2 5 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD AUG PY 1991 VL 93 IS 3 BP 676 EP 682 DI 10.2307/1368199 PG 7 WC Ornithology SC Zoology GA GG626 UT WOS:A1991GG62600021 ER PT J AU KRAPU, GL DWYER, CP LUNA, CR AF KRAPU, GL DWYER, CP LUNA, CR TI ORPHANED MALLARD BROOD TRAVELS ALONE FROM NEST TO WATER SO CONDOR LA English DT Note DE MALLARD; ANAS-PLATYRHYNCHOS; BROOD; DROUGHT; TRAVEL; MORTALITY RP KRAPU, GL (reprint author), US FISH & WILDLIFE SERV,NO PRAIRIE WILDLIFE RES CTR,BOX 2096,JAMESTOWN,ND 58402, USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD AUG PY 1991 VL 93 IS 3 BP 779 EP 781 DI 10.2307/1368217 PG 3 WC Ornithology SC Zoology GA GG626 UT WOS:A1991GG62600039 ER PT J AU SEDGWICK, JA KNOPF, FL AF SEDGWICK, JA KNOPF, FL TI THE LOSS OF AVIAN CAVITIES BY INJURY COMPARTMENTALIZATION SO CONDOR LA English DT Note DE COMPARTMENTALIZATION OF INJURY; CAVITY-NESTING BIRDS; CAVITY DYNAMICS; COTTONWOOD BOTTOMLANDS; COLORADO RP SEDGWICK, JA (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,4512 MCMURRY,FT COLLINS,CO 80525, USA. NR 5 TC 9 Z9 10 U1 0 U2 2 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD AUG PY 1991 VL 93 IS 3 BP 781 EP 783 DI 10.2307/1368218 PG 3 WC Ornithology SC Zoology GA GG626 UT WOS:A1991GG62600040 ER PT J AU FIELD, ME AF FIELD, ME TI SYMPOSIUM REVIEW OF THE SURFICIAL GEOLOGY OF CANADIAN CONTINENTAL SHELVES SO CONTINENTAL SHELF RESEARCH LA English DT Editorial Material RP FIELD, ME (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS-999,MENLO PK,CA 94025, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD AUG-OCT PY 1991 VL 11 IS 8-10 BP 1299 EP 1302 DI 10.1016/0278-4343(91)90104-E PG 4 WC Oceanography SC Oceanography GA GN704 UT WOS:A1991GN70400033 ER PT J AU WALKER, RJ MORGAN, JW NALDRETT, AJ LI, C FASSETT, JD AF WALKER, RJ MORGAN, JW NALDRETT, AJ LI, C FASSETT, JD TI RE-OS ISOTOPE SYSTEMATICS OF NI-CU SULFIDE ORES, SUDBURY IGNEOUS COMPLEX, ONTARIO - EVIDENCE FOR A MAJOR CRUSTAL COMPONENT SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article ID IONIZATION MASS-SPECTROMETRY; OSMIUM; RHENIUM; DEPOSITS; QUANTITIES; METEORITES; EVOLUTION; ELEMENTS; SILICATE; ORIGIN AB Sudbury Igneous Complex sublayer ores from the Levack West, Falconbridge and Strathcona mines were analyzed for their Re and Os concentrations and Os isotopic compositions. The Re-Os isotope systematics of three ores from the different mines give isochron ages of 1840 +/- 60 Ma, 1770 +/- 60 Ma and 1780 +/- 110 Ma, suggesting that the Re-Os system became closed at the time of, or soon after the 1850 +/- 1 Ma crystallization age of the complex. The Os isotopic compositions of different portions of the complex at the time of crystallization varied considerably, with initial Os-187/Os-186(1850) ranging from 4.64 at Levack West to 7.55 at Strathcona. These hetergeneities require that the Os, and probably also the other platinum-group elements contained in the ores, were derived from at least two sources. In addition, the high initial Os-187/Os-186 ratios indicate that the Os was derived predominantly from ancient crust. Previous studies have suggested that the complex either crystallized from a mixture of mantle-derived basaltic melt and ancient continental crust, or was derived exclusively from the fusion of ancient continental crust resulting from a meteorite impact. Results of modelling suggest that if a contemporaneous mantle-derived basaltic melt was involved in the origin of the SIC, it likely contributed < 50% of the Os to all three ores. The large percentage of ancient crust involved in the production of the ores is most consistent with an interpretation of substantial crustal fusion resulting from meteorite impact. C1 US GEOL SURVEY,RESTON,VA 22092. UNIV TORONTO,DEPT GEOL,TORONTO M5S 1A1,ONTARIO,CANADA. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP WALKER, RJ (reprint author), UNIV MARYLAND,DEPT GEOL,COLLEGE PK,MD 20742, USA. RI Li, Chusi/E-5592-2011; Walker, Richard/K-6869-2016 OI Li, Chusi/0000-0002-0426-8157; Walker, Richard/0000-0003-0348-2407 NR 44 TC 117 Z9 129 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD AUG PY 1991 VL 105 IS 4 BP 416 EP 429 DI 10.1016/0012-821X(91)90182-H PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GG289 UT WOS:A1991GG28900006 ER PT J AU GERLACH, TM AF GERLACH, TM TI MIDOCEAN RIDGE POPPING ROCKS - IMPLICATIONS FOR DEGASSING AT RIDGE CRESTS - COMMENT SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Note ID CARBON-DIOXIDE; BASALTIC GLASSES; ISOTOPES RP GERLACH, TM (reprint author), US GEOL SURVEY,CASCADES VOLCANO OBSERV,5400 MACARTHUR BLVD,VANCOUVER,WA 98661, USA. NR 10 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD AUG PY 1991 VL 105 IS 4 BP 566 EP 567 DI 10.1016/0012-821X(91)90193-L PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GG289 UT WOS:A1991GG28900017 ER PT J AU LINK, WA HOOVER, BA AF LINK, WA HOOVER, BA TI THE DETECTION OF DENSITY-DEPENDENCE FROM A SERIES OF ANNUAL CENSUSES - A COMMENT SO ECOLOGY LA English DT Note RP LINK, WA (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 2 TC 3 Z9 3 U1 0 U2 0 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9658 J9 ECOLOGY JI Ecology PD AUG PY 1991 VL 72 IS 4 BP 1514 EP 1515 DI 10.2307/1941128 PG 2 WC Ecology SC Environmental Sciences & Ecology GA GB185 UT WOS:A1991GB18500039 ER PT J AU OHLENDORF, HM MAROIS, KC LOWE, RW HARVEY, TE KELLY, PR AF OHLENDORF, HM MAROIS, KC LOWE, RW HARVEY, TE KELLY, PR TI TRACE-ELEMENTS AND ORGANOCHLORINES IN SURF SCOTERS FROM SAN-FRANCISCO BAY, 1985 SO ENVIRONMENTAL MONITORING AND ASSESSMENT LA English DT Article AB Surf scoters (Melanitta perspicillata) were collected from 6 locations in San Francisco Bay during January and March 1985. Overall, mean concentrations of cadmium and zinc were higher in livers of scoters from the southern region of the Bay, whereas mean iron and lead were higher in those from the northern Bay region. Mean concentrations of arsenic, copper, lead, zinc, aluminum (January only) and iron (January) also differed among individual locations. Mean concentrations of copper and zinc increased, arsenic decreased, and cadmium remained the same between January and March. Selenium and mercury concentrations in scoter livers were not significantly correlated (P > 0.05), but cadmium concentrations in livers and kidneys were positively correlated (P < 0.0001), and body weight was negatively related to mercury concentration in the liver (P < 0.05). Body weight differed among locations but not between January and March. Body weight was correlated with lipid content (P < 0.0001). DDE and PCBs were each detected in 34 of 36 scoter carcasses. DDE increased significantly between January and March at Richmond Harbor, but BCBs did not differ between January and March at the 3 locations that could be tested. C1 UNIV CALIF DAVIS,DEPT WILDLIFE & FISHERIES BIOL,US FISH & WILDLIFE SERV,DAVIS,CA 95616. NR 0 TC 34 Z9 34 U1 2 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-6369 J9 ENVIRON MONIT ASSESS JI Environ. Monit. Assess. PD AUG PY 1991 VL 18 IS 2 BP 105 EP 122 DI 10.1007/BF00394973 PG 18 WC Environmental Sciences SC Environmental Sciences & Ecology GA GC586 UT WOS:A1991GC58600002 PM 24233749 ER PT J AU HAGEE, B BERNATOWICZ, TJ PODOSEK, FA JOHNSON, ML BURNETT, DS TATSUMOTO, M AF HAGEE, B BERNATOWICZ, TJ PODOSEK, FA JOHNSON, ML BURNETT, DS TATSUMOTO, M TI ACTINIDE ABUNDANCES IN ORDINARY CHONDRITES - REPLY SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID XENON ISOTOPE ANOMALIES; SOLAR-SYSTEM; MURRAY C1 WASHINGTON UNIV,MCDONNELL CTR SPACE SCI,ST LOUIS,MO 63130. CALTECH,DIV GEOL & PLANETARY SCI,PASADENA,CA 91125. US GEOL SURVEY,LAKEWOOD,CO 80225. NR 28 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD AUG PY 1991 VL 55 IS 8 BP 2359 EP 2363 DI 10.1016/0016-7037(91)90111-H PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GC439 UT WOS:A1991GC43900022 ER PT J AU SCHLEE, JS ROBB, JM AF SCHLEE, JS ROBB, JM TI SUBMARINE PROCESSES OF THE MIDDLE ATLANTIC CONTINENTAL RISE BASED ON GLORIA IMAGERY SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID BALTIMORE CANYON; NORTH-ATLANTIC; SLOPE; SEDIMENTATION; CHARACTER; CHANNELS; FAN AB Approximately 6,100 km of 3.5-kHz echo-sounding profiles was correlated with a GLORIA side-scan sonar image of the mid-Atlantic United States (34-degrees-N, 70-degrees-W) lower slope-upper continental rise. The image allows us to map the major erosional and depositional features and to identify major processes that have shaped the area. The GLORIA imagery shows three approximately triangular-shaped sediment-gather areas that cover the upper-rise and slope transition areas near Wilmington, Baltimore, and Norfolk Canyons. The gather areas, which are interspersed with hemipelagic drape areas, are composed of dendritic networks of channels that extend from the base of the slope toward major channel systems on the middle rise, such as Wilmington Valley. Seaward of Cape Hatteras, a tongue-shaped area of mottled high back scatter on the GLORIA imagery denotes the Albemarle-Currituck mass-movement complex, a large (60 km wide by > 190 km long) area of the sea floor that is marked by the disruption of upper-rise sedimentary strata and by mass-flow deposits. Interpretation of GLORIA imagery and echo-sounding profiles indicates that mass movement is the predominant process affecting sediment on the United States east coast mid-Atlantic slope and upper rise and that isobath-parallel sediment movement by geostrophic currents is restricted mainly to the lower continental rise. The mass-movement processes evident on the rise probably were most active during the Pleistocene, when sea level was lower and sediment input more active. RP SCHLEE, JS (reprint author), US GEOL SURVEY,WOODS HOLE,MA 02543, USA. NR 33 TC 14 Z9 14 U1 0 U2 2 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD AUG PY 1991 VL 103 IS 8 BP 1090 EP 1103 DI 10.1130/0016-7606(1991)103<1090:SPOTMA>2.3.CO;2 PG 14 WC Geosciences, Multidisciplinary SC Geology GA GA305 UT WOS:A1991GA30500010 ER PT J AU FOURNIER, RO THOMPSON, JM CUNNINGHAM, CG HUTCHINSON, RA AF FOURNIER, RO THOMPSON, JM CUNNINGHAM, CG HUTCHINSON, RA TI CONDITIONS LEADING TO A RECENT SMALL HYDROTHERMAL EXPLOSION AT YELLOWSTONE-NATIONAL-PARK SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID CA AB Porkchop Geyser, in Yellowstone National Park, was the site of a small hydrothermal explosion on September 5, 1989. In the early 1960s, this was a quiescent spring with an intermittent seeping discharge. Infrequent geyser eruptions 3-5 m high started in 1971, and in 1985 the geyser began erupting as a perpetual spouter 6-9 m high. Perpetual spouting at the latter height continued until just before the catastrophic hydrothermal event when the geyser column suddenly rose to a height of 20-30 m, followed immediately by the explosive ejection of sinter blocks up to 1.88 m in maximum dimension and formation of an irregular crater 13.9 m long and 11.7 m wide. The ejected blocks show a variety of siliceous deposits indicative of changing environments of deposition with time, and possibly of prior hydrothermal explosive activity at this site. Water samples from Porkchop were collected and analyzed once in the 1920s, again in 1951, ten times between 1960 and mid-1989, and once in January 1990 after the explosion. Chemical geothermometry shows an increase in the temperature of last water-rock equilibration of about 60 to 70-degrees-C from 1962 through 1989. This may have been the result of drawing water progressively from different and hotter regions of a single reservoir or mixing waters from two different reservoirs with a progressively larger proportion of water being drawn from the hotter reservoir from 1962 through 1989. Boiling of ascending fluids coming from hotter subsurface regions resulted in an increase in the proportion of steam to water discharged by the geyser. A constriction at the exit of the geyser tube throttled the flow of water and steam and allowed water in shallow cavities adjacent to the geyser tube to become heated to the boiling point at pressures greater than normal hydrostatic. We hypothesize that a sudden breaking loose of this constriction, likely triggered by a seasonal increase in subsurface boiling throughout Norris Basin, allowed water and steam to be discharged from Porkchop much more rapidly than previously. This resulted in a drop in pressure within the geyser tube, causing water in adjacent connected chambers to become superheated. An ensuing rapid flashing of superheated water to steam within relatively confined spaces resulted in the hydrothermal explosion. C1 NATL PK SERV,YELLOWSTONE NATL PK,WY 82190. RP FOURNIER, RO (reprint author), US GEOL SURVEY,MS 910,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 23 TC 26 Z9 26 U1 1 U2 3 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD AUG PY 1991 VL 103 IS 8 BP 1114 EP 1120 DI 10.1130/0016-7606(1991)103<1114:CLTARS>2.3.CO;2 PG 7 WC Geosciences, Multidisciplinary SC Geology GA GA305 UT WOS:A1991GA30500013 ER PT J AU BAUM, RL FLEMING, RW AF BAUM, RL FLEMING, RW TI USE OF LONGITUDINAL STRAIN IN IDENTIFYING DRIVING AND RESISTING ELEMENTS OF LANDSLIDES SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article AB Observations of deformation at the surfaces of landslides in Utah and Hawaii indicate that the upslope parts of the landslides have stretched and the downslope parts have shortened parallel with the direction of movement. The maximum displacement of each landslide occurs in a relatively undeformed zone between the zones of shortening and stretching. The pattern of deformation at the surface of these landslides may be useful in analyzing their mechanics by helping to constrain the longitudinal forces in limit-equilibrium stability analysis. We used earth-pressure calculations to determine the range of possible longitudinal forces (per unit width) for active failure in the zone of stretching and for passive failure in the zone of shortening of one of the Hawaiian landslides. Longitudinal forces computed by stability analysis, assuming homogeneous strength, exceeded the possible forces in much of the upslope half of the landslide. Consequently, we assumed inhomogeneous strength and adjusted shear-strength parameters at each segment of the slip surface until the longitudinal forces computed by stability analysis agreed with those computed by earth-pressure theory, and the factor of safety approached unity. The distribution of longitudinal forces computed for inhomogeneous strength indicated that the boundary between driving and resisting elements of the landslide is near the thickest part of the slide, in agreement with a simple formula for the location of the boundary. RP BAUM, RL (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 966,BOX 25046,DENVER,CO 80225, USA. OI Baum, Rex/0000-0001-5337-1970 NR 23 TC 34 Z9 34 U1 0 U2 2 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD AUG PY 1991 VL 103 IS 8 BP 1121 EP 1132 DI 10.1130/0016-7606(1991)103<1121:UOLSII>2.3.CO;2 PG 12 WC Geosciences, Multidisciplinary SC Geology GA GA305 UT WOS:A1991GA30500014 ER PT J AU JOHNSON, LE FRYER, P TAYLOR, B SILK, M JONES, DL SLITER, WV ITAYA, T ISHII, T AF JOHNSON, LE FRYER, P TAYLOR, B SILK, M JONES, DL SLITER, WV ITAYA, T ISHII, T TI NEW EVIDENCE FOR CRUSTAL ACCRETION IN THE OUTER MARIANA FORE ARC - CRETACEOUS RADIOLARIAN CHERTS AND MIDOCEAN RIDGE BASALT-LIKE LAVAS SO GEOLOGY LA English DT Article ID TRENCH; GEOCHEMISTRY; SUBDUCTION; EVOLUTION; PACIFIC; ROCKS; JAPAN AB New age determinations on radiolarian cherts, foraminifers, and volcanic rocks document the presence of allochthonous fragments of Cretaceous oceanic plate, suggesting accreted terrane, in the outer Mariana fore arc, more than 50 km from the trench. Three dredges, from a 3 km2 area along a steep scarp, recovered a diverse assemblage of rocks representing an ophiolite suite (chert, mafic and intermediate lavas and intrusive rocks). Trace element patterns of the lavas suggest at least three tectonic associations (island arc, ocean island, and oceanic plate). The cherts contain two deep-water assemblages of radiolaria of middle to late Valanginian (131-138 Ma) and Albian (97-112 Ma) age. Foraminifers recovered with the chert are Aptian to Albian in age. The lavas record a wide range of K-Ar ages, 85 Ma for a metabasalt with trace-element signatures of mid-ocean ridge basalt, 71 Ma for a highly metamorphosed alkalic basalt, and 39 Ma for a fresh glassy boninite. These ages imply multiple volcanic events and at least two tectonic settings for magma genesis. The cherts and metabasalts are too old to have formed in situ or to be part of trapped West Philippine Basin crust. The mix of old oceanic plate with younger arc rocks requires complex tectonic relations. We suggest that one or more fragments of Cretaceous oceanic plate (chert, mid-ocean ridge basalt, and alkalic lavas) were accreted to the Mariana fore arc and have been extensively faulted and probably intruded by arc lava (island-arc tholeiite and boninite). C1 UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY,CA 94720. US GEOL SURVEY,PALEONTOL & STRATIG BRANCH,MENLO PK,CA 94025. OKAYAMA UNIV SCI,HIRUZEN RES INST,OKAYAMA 700,JAPAN. UNIV TOKYO,OCEAN RES INST,NAKANI KU,TOKYO 164,JAPAN. RP JOHNSON, LE (reprint author), UNIV HAWAII,SCH OCEAN & EARTH SCI TECHNOL,2525 CORREA RD,HONOLULU,HI 96822, USA. NR 34 TC 36 Z9 36 U1 0 U2 4 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD AUG PY 1991 VL 19 IS 8 BP 811 EP 814 DI 10.1130/0091-7613(1991)019<0811:NEFCAI>2.3.CO;2 PG 4 WC Geology SC Geology GA GA306 UT WOS:A1991GA30600011 ER PT J AU BROCHER, TM CHRISTENSEN, NI AF BROCHER, TM CHRISTENSEN, NI TI SEISMIC ANISOTROPY DUE TO PREFERRED MINERAL ORIENTATION OBSERVED IN SHALLOW CRUSTAL ROCKS IN SOUTHERN ALASKA - REPLY SO GEOLOGY LA English DT Note C1 PURDUE UNIV,DEPT EARTH & ATMOSPHER SCI,W LAFAYETTE,IN 47907. RP BROCHER, TM (reprint author), US GEOL SURVEY,MS 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. OI Brocher, Thomas/0000-0002-9740-839X NR 0 TC 1 Z9 1 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD AUG PY 1991 VL 19 IS 8 BP 859 EP 860 PG 2 WC Geology SC Geology GA GA306 UT WOS:A1991GA30600024 ER PT J AU HAGSTRUM, JT LIPMAN, PW AF HAGSTRUM, JT LIPMAN, PW TI PALEOMAGNETISM OF 3 UPPER JURASSIC ASH-FLOW SHEETS IN SOUTHEASTERN ARIZONA - IMPLICATIONS FOR REGIONAL DEFORMATION SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID COLORADO PLATEAU; NORTH-AMERICA; ROTATION; NEVADA; TUFF AB A sequence of three petrologically distinct Upper Jurassic ash-flow tuffs has been sampled for paleomagnetic analysis in the Huachuca Mountains, Canelo Hills, and Mustang Mountains of southeastern Arizona. Site-mean paleomagnetic directions for these units indicate significant vertical-axis rotations between sampling localities (congruent-to 15-degrees-40-degrees), and a comparison of these and previously published data with reference directions from the Colorado Plateau implies that the Jurassic rocks in southeastern Arizona have been rotated in a clockwise sense with respect to stable North America. These new data are consistent with paleomagnetic results showing clockwise rotation of Upper Cretaceous rocks in south central Arizona, and further indicate that studies of North American apparent polar wander based on rocks from southern Arizona could be subject to error. The clockwise rotations in southern Arizona are likely related to Late Cretaceous and early Tertiary strike-slip movement on northwest-trending high-angle faults in the region, and this movement may be linked to an increase in oblique Farallon-North American plate convergence at that time. RP HAGSTRUM, JT (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 937,MENLO PK,CA 94025, USA. NR 27 TC 10 Z9 10 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1413 EP 1416 DI 10.1029/91GL01805 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000011 ER PT J AU EICHELBERGER, JC HILDRETH, W PAPIKE, JJ AF EICHELBERGER, JC HILDRETH, W PAPIKE, JJ TI THE KATMAI SCIENTIFIC DRILLING PROJECT, SURFACE PHASE - INVESTIGATION OF AN EXCEPTIONAL IGNEOUS SYSTEM SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NATIONAL-PARK; VALLEY; SMOKES; ALASKA AB Explosive volcanism is the response of magma to rapid decompression. Inherent complexity of volcanoes and lack of observations at depth in young systems are impediments to proper understanding of this important phenomenon. The Katmai Scientific Drilling Project is an interdisciplinary surface and drilling investigation of an exceptionally large and relatively simple explosive volcanic event that occurred in Alaska's Aleutian Range in 1912. The surface phase of the project is now largely complete, and results are presented in the papers that follow. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. US GEOL SURVEY,MENLO PK,CA 94025. UNIV NEW MEXICO,INST METEORIT,ALBUQUERQUE,NM 87131. RI Eichelberger, John/H-6199-2016 NR 22 TC 4 Z9 4 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1513 EP 1516 DI 10.1029/91GL01472 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000036 ER PT J AU KLEINMAN, JW IWATSUBO, EY AF KLEINMAN, JW IWATSUBO, EY TI A GEODETIC NETWORK IN THE NOVARUPTA AREA, KATMAI NATIONAL-PARK, ALASKA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB A small geodetic network was established in 1989 and 1990 to monitor ground deformation in the Novarupta area, Katmai National Park, Alaska. Slope distances and zenith angles for three lines were repeated in 1990. A comparison of the two surveys indicates changes that are within the error of the measurements. Mean mark-to-mark slope distance changes are 1.17 +/- 1.46 ppm. Two benchmarks were added to the network in 1990 to configure a five-endpoint braced quadrilateral centered about the Novarupta dome. RP KLEINMAN, JW (reprint author), US GEOL SURVEY,CASCADES VOLCANO OBSERV,5400 MACARTHUR,VANCOUVER,WA 98661, USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1517 EP 1519 DI 10.1029/91GL01185 PG 3 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000037 ER PT J AU WARD, PL PITT, AM ENDO, E AF WARD, PL PITT, AM ENDO, E TI SEISMIC EVIDENCE FOR MAGMA IN THE VICINITY OF MT KATMAI, ALASKA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NATIONAL-PARK; VALLEY; CALIFORNIA; SMOKES AB P-wave traveltime delays of as much as 0.9 sec are consistently observed at one seismic station from local and regional earthquakes 70 to 150 km deep. This station is on the southwest flank of Mt. Trident, the most recently active volcano within Katmai National Park, Alaska. Delays from local shallow earthquakes are typically less than 0.3 sec, suggesting that most of the major delay results from anomalous material at depths of more than a few kilometers. This station is located near the center of a bowl-shaped low in the Bouguer gravity field that is approximately 15 km in diameter and more than 25 mgals deep. These anomalies suggest, but do not prove, the presence of considerable amounts of magma in the shallow part of the curst that could have been the source for all magma erupted in the vicinity of Mt. Katmai and Mt. Trident this century. C1 US GEOL SURVEY,JEDDAH 21431,SAUDI ARABIA. RP WARD, PL (reprint author), US GEOL SURVEY,MAIL STOP 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 27 TC 16 Z9 16 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1537 EP 1540 DI 10.1029/91GL01906 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000042 ER PT J AU HILDRETH, W AF HILDRETH, W TI THE TIMING OF CALDERA COLLAPSE AT MOUNT KATMAI IN RESPONSE TO MAGMA WITHDRAWAL TOWARD NOVARUPTA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Several thin layers of nonjuvenile lithic-rich tephra from Mount Katmai are intercalated with 1912 plinian pumice-fall deposits that originated at Novarupta 10 km away, demonstrating that caldera collapse at Katmai and eruption at Novarupta were synchronous. Emplaced by phreatic explosions and avalanche-generated dustclouds, each Katmai-derived layer is thickest and coarsest at the caldera rim and pinches out within 5-8 km. In contrast, thicknesses and clast sizes of plinian Layers A-G decrease radially away from Novarupta. The first Katmai-derived layer lies between Novarupta-derived Layers B2 and B3, indicating that collapse began after release of approximately 6.9 km3 of magma at Novarupta. The first major earthquake (M(s) = 6.5) at 2356 h on 6 June, approximately 11 hours after the eruption began, may have marked the onset of collapse. The Katmai River landslide and several debris-flow deposits are also sandwiched within the plinian deposits, indicating that they too were emplaced during the eruption. RP HILDRETH, W (reprint author), US GEOL SURVEY,MS 910,MENLO PK,CA 94025, USA. NR 6 TC 38 Z9 38 U1 2 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1541 EP 1544 DI 10.1029/91GL01083 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000043 ER PT J AU PAPIKE, JJ KEITH, TEC SPILDE, MN SHEARER, CK GALBREATH, KC LAUL, JC AF PAPIKE, JJ KEITH, TEC SPILDE, MN SHEARER, CK GALBREATH, KC LAUL, JC TI MAJOR AND TRACE-ELEMENT MASS FLUX IN FUMAROLIC DEPOSITS, VALLEY OF 10000 SMOKES, ALASKA - RHYOLITE-RICH PROTOLITH SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Three fossil fumaroles in rhyolite-rich ash-flow tuff from the lower Valley of Ten Thousand Smokes (VTTS) have been studied to ascertain chemical losses and gains and mineralogical evolution during fumarolic alteration and subsequent cooling and weathering processes. Major oxide and trace element data were interpreted using the isocon method of Grant (1986). C1 US GEOL SURVEY,MENLO PK,CA 94025. UNIV N DAKOTA,GRAND FORKS,ND 58202. EG&G,GOLDEN,CO 80402. RP PAPIKE, JJ (reprint author), UNIV NEW MEXICO,INST METEOR,DEPT GEOL,ALBUQUERQUE,NM 87131, USA. NR 12 TC 8 Z9 8 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1545 EP 1548 DI 10.1029/91GL01142 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000044 ER PT J AU KEITH, TEC AF KEITH, TEC TI ARGILLIC ALTERATION IN THE NOVARUPTA VENT REGION, KATMAI NATIONAL-PARK, ALASKA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Secondary mineralogy in the 1912 vent region at Novarupta illustrates an alteration history that evolved from high-temperature degassing of ejecta through surficial argillic alteration to near-neutral, wet-steam alteration as the post-eruptive volcanic system cooled. The locallized distribution of surficial argillization appears to have been controlled mainly by fractures related to slumping and compaction in the near-surface fallback ejecta. The fractures guiding the surviving warm, near-neutral fumarolic fluids, however, must be connected with deeper vent structures that reach a subsurface heat source, perhaps the boiling zone of a hydrothermal system. Trace metals, including Mo, Pb, Cu, Cd, and Zn, concentrated by high-temperature, vapor-phase mobilization, have subsequently been partly removed by argillization processes; in contrast, Hg, Sb, Tl, Bi, and As remain high even though the fumaroles now emit only low-temperature, near-neutral wet steam. RP KEITH, TEC (reprint author), US GEOL SURVEY,MS 910,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 14 TC 5 Z9 5 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1549 EP 1552 DI 10.1029/91GL01350 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000045 ER PT J AU LOWELL, RP KEITH, TEC AF LOWELL, RP KEITH, TEC TI CHEMICAL AND THERMAL CONSTRAINTS ON MODELS OF THERMAL SPRINGS VALLEY OF 10000 SMOKES, ALASKA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Thermal (15-30-degrees-C) springs issuing from 1912 ash-flow tuff in the mid-valley region of the Valley of Ten Thousand Smokes consist of meteoric water that may have been heated by an incompletely cooled lens of welded tuff upvalley from the springs. Conductive cooling of the thermal waters along the flow path is the likely cause for the difference between the observed spring temperatures and the source temperature inferred from chemical geothermometry. Conductive cooling alone can not easily account for the seasonal fluctuations in spring temperatures, however. Mixing of the thermal waters with cold meteoric waters would seem a likely possibility; but thermal water chemistry is constant, indicating that mixing does not occur after the water leaves the zone of heating. Even if mixing occurred, simple mixing models do not account totally for the observed temperature differences of the springs from late spring to summer. The geochemical and thermal data argue for a complex hydrological and thermal regime. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP LOWELL, RP (reprint author), GEORGIA INST TECHNOL,SCH EARTH & ATMOSPHER SCI,ATLANTA,GA 30332, USA. NR 6 TC 7 Z9 7 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG PY 1991 VL 18 IS 8 BP 1553 EP 1556 DI 10.1029/91GL01758 PG 4 WC Geosciences, Multidisciplinary SC Geology GA GB150 UT WOS:A1991GB15000046 ER PT J AU GUNDERSEN, LCS AF GUNDERSEN, LCS TI FOCUS ON RADON AND RADIONUCLIDES SO GEOTIMES LA English DT Article RP GUNDERSEN, LCS (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 939,DENVER,CO 80225, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOLOGICAL INST PI ALEXANDRIA PA 4220 KING ST, ALEXANDRIA, VA 22302-1507 SN 0016-8556 J9 GEOTIMES JI Geotimes PD AUG PY 1991 VL 36 IS 8 BP 17 EP 18 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FZ441 UT WOS:A1991FZ44100022 ER PT J AU OSTERKAMP, WR EMMETT, WW LEOPOLD, LB AF OSTERKAMP, WR EMMETT, WW LEOPOLD, LB TI THE VIGIL NETWORK - A MEANS OF OBSERVING LANDSCAPE CHANGE IN DRAINAGE BASINS SO HYDROLOGICAL SCIENCES JOURNAL-JOURNAL DES SCIENCES HYDROLOGIQUES LA English DT Article AB Long-term monitoring of geomorphic, hydrological, and biological characteristics of landscapes provides an effective means of relating observed change to possible causes of the change. Identification of changes in basin characteristics, especially in arid areas where the response to altered climate or land use is generally rapid and readily apparent, might provide the initial direct indications that factors such as global warming and cultural impacts have affected the environment. The Vigil Network provides an opportunity for earth and life scientists to participate in a systematic monitoring effort to detect landscape changes over time, and to relate such changes to possible causes. The Vigil Network is an ever-increasing group of sites and basins used to monitor landscape features with as much as 50 years of documented geomorphic and related observations. RP OSTERKAMP, WR (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,DENVER FED CTR,BOX 25046 MS413,DENVER,CO 80225, USA. NR 0 TC 6 Z9 6 U1 1 U2 1 PU IAHS PRESS, INST HYDROLOGY PI WALLINGFORD PA C/O SARAH CAGE, WALLINGFORD, ENGLAND OX10 8BB SN 0262-6667 J9 HYDROLOG SCI J JI Hydrol. Sci. J.-J. Sci. Hydrol. PD AUG PY 1991 VL 36 IS 4 BP 331 EP 344 DI 10.1080/02626669109492518 PG 14 WC Water Resources SC Water Resources GA FX563 UT WOS:A1991FX56300002 ER PT J AU MCEWEN, AS AF MCEWEN, AS TI PHOTOMETRIC FUNCTIONS FOR PHOTOCLINOMETRY AND OTHER APPLICATIONS SO ICARUS LA English DT Article ID BIDIRECTIONAL REFLECTANCE SPECTROSCOPY; DISK-INTEGRATED PHOTOMETRY; MULTIPLE-SCATTERING; RADIATIVE-TRANSFER; ICY SATELLITES; URANUS; SURFACES; ALBEDO; IO; PARAMETERS RP MCEWEN, AS (reprint author), US GEOL SURVEY,2255 N GEMINI DR,FLAGSTAFF,AZ 86001, USA. NR 49 TC 108 Z9 108 U1 0 U2 5 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0019-1035 J9 ICARUS JI Icarus PD AUG PY 1991 VL 92 IS 2 BP 298 EP 311 DI 10.1016/0019-1035(91)90053-V PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA GA979 UT WOS:A1991GA97900010 ER PT J AU METHVEN, DA PIATT, JF AF METHVEN, DA PIATT, JF TI SEASONAL ABUNDANCE AND VERTICAL-DISTRIBUTION OF CAPELIN (MALLOTUS-VILLOSUS) IN RELATION TO WATER TEMPERATURE AT A COASTAL SITE OFF EASTERN NEWFOUNDLAND SO ICES JOURNAL OF MARINE SCIENCE LA English DT Article ID SOUTHERN LABRADOR CURRENT; COD GADUS-MORHUA; SCHOOLING FISH; GROWTH; ECOLOGY; SCALE; DIET; PREY C1 US FISH & WILDLIFE SERV,ALASKA FISH & WILDLIFE RES CTR,ANCHORAGE,AK 99503. RP METHVEN, DA (reprint author), MEM UNIV NEWFOUNDLAND,CTR OCEAN SCI,ST JOHNS A1C 5S7,NEWFOUNDLAND,CANADA. NR 36 TC 18 Z9 19 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 1054-3139 J9 ICES J MAR SCI JI ICES J. Mar. Sci. PD AUG PY 1991 VL 48 IS 2 BP 187 EP 193 DI 10.1093/icesjms/48.2.187 PG 7 WC Fisheries; Marine & Freshwater Biology; Oceanography SC Fisheries; Marine & Freshwater Biology; Oceanography GA GH043 UT WOS:A1991GH04300005 ER PT J AU FLEAGLE, JG RASMUSSEN, DT YIRGA, S BOWN, TM GRINE, FE AF FLEAGLE, JG RASMUSSEN, DT YIRGA, S BOWN, TM GRINE, FE TI NEW HOMINID FOSSILS FROM FEJEJ, SOUTHERN ETHIOPIA SO JOURNAL OF HUMAN EVOLUTION LA English DT Article ID KENYA C1 UNIV CALIF LOS ANGELES,DEPT ANTHROPOL,LOS ANGELES,CA 90024. US GEOL SURVEY,CTR FED,DENVER,CO 80225. SUNY STONY BROOK,HLTH SCI CTR,DEPT ANTHROPOL,STONY BROOK,NY 11794. RP FLEAGLE, JG (reprint author), SUNY STONY BROOK,HLTH SCI CTR,DEPT ANAT SCI,STONY BROOK,NY 11794, USA. NR 17 TC 35 Z9 36 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD AUG PY 1991 VL 21 IS 2 BP 145 EP 152 DI 10.1016/0047-2484(91)90005-G PG 8 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA GA621 UT WOS:A1991GA62100005 ER PT J AU DELONG, LL AF DELONG, LL TI MASS CONSERVATION - 1-D OPEN CHANNEL FLOW EQUATIONS - CLOSURE SO JOURNAL OF HYDRAULIC ENGINEERING-ASCE LA English DT Discussion RP DELONG, LL (reprint author), US GEOL SURVEY,BLDG 2101,STENNIS SPACE CTR,MS 39529, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9429 J9 J HYDRAUL ENG-ASCE JI J. Hydraul. Eng.-ASCE PD AUG PY 1991 VL 117 IS 8 BP 1080 EP 1082 DI 10.1061/(ASCE)0733-9429(1991)117:8(1080.2) PG 3 WC Engineering, Civil; Engineering, Mechanical; Water Resources SC Engineering; Water Resources GA FY167 UT WOS:A1991FY16700009 ER PT J AU CELEBI, M SAFAK, E AF CELEBI, M SAFAK, E TI SEISMIC RESPONSE OF TRANSAMERICA BUILDING .1. DATA AND PRELIMINARY-ANALYSIS SO JOURNAL OF STRUCTURAL ENGINEERING-ASCE LA English DT Article AB The objective of this paper is to present preliminary analyses of a set of acceleration response records obtained during the October 17, 1989 Loma Prieta earthquake (M(s) = 7.1) from the 60-story vertically tapered, pyramid-shaped Transamerica Building-a landmark of San Francisco. The building was instrumented in 1985 with 22 channels of synchronized sensors consisting of 13 uniaxial accelerometers deployed throughout the structure and connected to a central recording system and three triaxial strong-motion accelerographs at three different levels of the structure. No free-field accelerographs are at the site. The acceleration records permit the study of the behavior of this unique structure. The predominant translational response of the building and the associated frequency at approximately 0.28 Hz are identified from the records and their Fourier amplitude spectra. The records do not indicate any significant torsional motion. However, there is rocking type soil-structure interaction, and an associated frequency of approximately 2.0 Hz is identified from the Fourier amplitude spectra of the differential motions between the ground level and that at the basement. In addition, the response spectra for the basement motions indicate significant resonance in both directions at a period of approximately 0.5 seconds. C1 US GEOL SURVEY,RES STRUCT ENGN,RESTON,VA 22092. RP CELEBI, M (reprint author), US GEOL SURVEY,RES CIVIL ENGN,MS-977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 10 TC 13 Z9 14 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9445 J9 J STRUCT ENG-ASCE JI J. Struct. Eng.-ASCE PD AUG PY 1991 VL 117 IS 8 BP 2389 EP 2404 PG 16 WC Construction & Building Technology; Engineering, Civil SC Construction & Building Technology; Engineering GA FY554 UT WOS:A1991FY55400011 ER PT J AU SAFAK, E CELEBI, M AF SAFAK, E CELEBI, M TI SEISMIC RESPONSE OF TRANSAMERICA BUILDING .2. SYSTEM-IDENTIFICATION SO JOURNAL OF STRUCTURAL ENGINEERING-ASCE LA English DT Article AB A detailed analysis of the recorded seismic response of the Transamerica Building during the October 17, 1989 Loma Prieta earthquake is presented. The system identification algorithm used for the analysis is based on the discrete-time linear filtering approach with least-squares approximation, and assumes a multi-input, single-output model for the building. Fifteen modes in the north-south direction, and 18 modes in the east-west direction are identified from the records. The analysis shows that the building's response to the earthquake was dominated by a coupled mode of vibration at 0.28 Hz in the southwest-northeast direction, which is almost parallel to one of the diagonals in the building's square cross section. The reason for this behavior is the symmetry of the building's structural characteristics, as well as the strong polarization of the S-waves of the earthquake. Several higher modes of the building were excited during the strong-motion part of the earthquake. The results also show a significant amount of rocking in the building at a frequency of 2.15 Hz. C1 US GEOL SURVEY,RES CIVIL ENGN,MENLO PK,CA 94025. RP SAFAK, E (reprint author), US GEOL SURVEY,RES STRUCT ENGN,MS-922,RESTON,VA 22092, USA. NR 5 TC 16 Z9 18 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9445 J9 J STRUCT ENG-ASCE JI J. Struct. Eng.-ASCE PD AUG PY 1991 VL 117 IS 8 BP 2405 EP 2425 PG 21 WC Construction & Building Technology; Engineering, Civil SC Construction & Building Technology; Engineering GA FY554 UT WOS:A1991FY55400012 ER PT J AU SAFAK, E CELEBI, M AF SAFAK, E CELEBI, M TI METHOD TO ESTIMATE CENTER OF RIGIDITY USING VIBRATION RECORDINGS - CLOSURE SO JOURNAL OF STRUCTURAL ENGINEERING-ASCE LA English DT Discussion RP SAFAK, E (reprint author), US GEOL SURVEY,RES STRUCT ENGN,MS-977,MENLO PK,CA 94025, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9445 J9 J STRUCT ENG-ASCE JI J. Struct. Eng.-ASCE PD AUG PY 1991 VL 117 IS 8 BP 2565 EP 2565 PG 1 WC Construction & Building Technology; Engineering, Civil SC Construction & Building Technology; Engineering GA FY554 UT WOS:A1991FY55400027 ER PT J AU DVORAK, JJ GASPARINI, P AF DVORAK, JJ GASPARINI, P TI HISTORY OF EARTHQUAKES AND VERTICAL GROUND MOVEMENT IN CAMPI FLEGREI CALDERA, SOUTHERN ITALY - COMPARISON OF PRECURSORY EVENTS TO THE AD.1538 ERUPTION OF MONTE NUOVO AND OF ACTIVITY SINCE 1968 SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID CALIFORNIA AB The record of felt earthquakes around Naples Bay in southern Italy is probably complete since the mid-15th century. According to this record, intense earthquake swarms originating beneath Campi Flegrei, an explosive caldera located along the north coast of Naples Bay, have occurred only twice: (1) before the only historical eruption in Campi Flegrei in 1538; and (2) from mid-1983 to December 1984. Earthquake activity during the earlier period, which began at least a few years, and possibly as many as 30 years, before the 1538 eruption, damaged many buildings in the city of Pozzuoli, located near the center of Campi Flegrei. Minor seismic activity, which consisted of only a few felt earthquakes, occurred from 1970 to 1971. The second period of intense earthquake swarms lasted from mid-1983 to 1984, again damaging many buildings in Pozzuoli. Two periods of uplift along the shoreline within Campi Flegrei have also been noted since the mid-15th century: (1) during the few decades before the 1538 eruption; and (2) as two distinct episodes since 1968. Uplift of a few meters probably occurred a few decades before the 1538 eruption; uplift of as much as 3.0 m has occurred in Pozzuoli since 1968. These similarities strongly suggest that, for the first time in 440 years, the same process that caused intense local earthquake swarms and uplift in the early 15OO's and led to an eruption in 1538, has again occurred beneath Campi Flegrei. Though no major seismicity or uplift has occurred since December 1984, because of the large amount of extensional strain accumulated during the past two decades, if a third episode of seismicity and rapid uplift occurs, it may lead to an eruption within several months after the resumption of activity. C1 NAPLES UNIV,DIPARTIMENTO GEOFIS & VULCANOL,I-80138 NAPLES,ITALY. RP DVORAK, JJ (reprint author), US GEOL SURVEY,HAWAIIAN VOLCANO OBSERV,HAWAII NATL PK,HI 96718, USA. NR 49 TC 54 Z9 54 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD AUG PY 1991 VL 48 IS 1-2 BP 77 EP 92 DI 10.1016/0377-0273(91)90034-W PG 16 WC Geosciences, Multidisciplinary SC Geology GA GE462 UT WOS:A1991GE46200006 ER PT J AU LIRER, L ROLANDI, G RUBIN, M AF LIRER, L ROLANDI, G RUBIN, M TI C-14 AGE OF THE MUSEUM BRECCIA (CAMPI FLEGREI) AND ITS RELEVANCE FOR THE ORIGIN OF THE CAMPANIAN IGNIMBRITE SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Note AB Field stratigraphic investigations and AMS C-14 dating of carbon particles in paleosols has resulted in a framework of the sequence and age of the pyroclastic products in the Campi Flegrei area of Southern Italy. The Museum Breccia cannot be the early phase of the Campanian Ignimbrite, as was previously believed, but is from a smaller and later eruption with an age of approximately 17,900 y B.P.. This date also precludes its correlation with the Neapolitan Yellow Tuff (12,000 y B.P.) C1 US GEOL SURVEY,971 NATL CTR,RESTON,VA 22092. RP LIRER, L (reprint author), DIPARTIMENTO GEOFIS & VULCANOL,LARGO S MARCELLINO 10,I-80138 NAPLES,ITALY. NR 11 TC 29 Z9 29 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD AUG PY 1991 VL 48 IS 1-2 BP 223 EP 227 DI 10.1016/0377-0273(91)90044-Z PG 5 WC Geosciences, Multidisciplinary SC Geology GA GE462 UT WOS:A1991GE46200016 ER PT J AU ATTANASI, ED AF ATTANASI, ED TI ALTERNATIVE NATURAL-GAS CONTRACT AND PRICING STRUCTURES AND INCENTIVES FOR THE LNG INDUSTRY SO NATURAL RESOURCES FORUM LA English DT Article AB Gas conversion to liquefied gas (LNG) and transport by LNG tankers is one option for meeting expanding gas consumption and for gas traded internationally. This paper examines the impact of the traditional gas contract provisions of indefinite pricing, market out price ceilings, and take-or-pay requirements on the profitability of LNG projects in the context of markets characterized by price and quantity uncertainty. Simulation experiments are used to examine and calibrate the effects of those provisions. The results provide guidance to operators, host countries and purchasers in structuring such contracts. The paper also assesses prospects of future expansion of world LNG capacity. RP ATTANASI, ED (reprint author), US GEOL SURVEY,US DEPT INTERIOR,RESTON,VA 22092, USA. NR 11 TC 1 Z9 1 U1 0 U2 2 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0165-0203 J9 NAT RESOUR FORUM PD AUG PY 1991 VL 15 IS 3 BP 190 EP 201 PG 12 WC Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology GA GE075 UT WOS:A1991GE07500003 ER PT J AU HONDA, M MCDOUGALL, I PATTERSON, DB DOULGERIS, A AF HONDA, M MCDOUGALL, I PATTERSON, DB DOULGERIS, A TI TERRESTRIAL PRIMORDIAL NEON - REPLY SO NATURE LA English DT Letter C1 US GEOL SURVEY,MENLO PK,CA 94025. RP HONDA, M (reprint author), AUSTRALIAN NATL UNIV,RES SCH EARTH SCI,GPO BOX 4,CANBERRA,ACT 2601,AUSTRALIA. OI Honda, Masahiko/0000-0002-9545-9855 NR 2 TC 3 Z9 3 U1 0 U2 2 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD AUG 1 PY 1991 VL 352 IS 6334 BP 388 EP 388 DI 10.1038/352388b0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FZ346 UT WOS:A1991FZ34600047 ER PT J AU WOLFE, JA AF WOLFE, JA TI PALEOBOTANICAL EVIDENCE FOR A JUNE IMPACT WINTER AT THE CRETACEOUS TERTIARY BOUNDARY SO NATURE LA English DT Article ID EXTINCTION; SPHERULES; MEXICO AB A LARGE bolide impact, such as that thought to have occurred at the Cretaceous/Tertiary (K/T) boundary, should produce large amounts of light-attenuating debris, thereby causing an 'impact winter' 1-3. Because of thermal buffering in the oceans, evidence for a brief (1-2 months 2-4) impact winter would be found only in terrestrial environments. Aquatic leaves in the K/T boundary section near Teapot Dome, Wyoming, preserve structural deformation that can be duplicated experimentally in extant aquatic leaves by freezing. Reproductive stages reached by the fossil aquatic plants at the time of death suggest that freezing took place in approximately early June. Both the existence of the structurally deformed plants and the high abundance of fern spores occur in a horizon containing sparse impact debris, but below the horizon containing abundant impact debris; I therefore suggest that the lower horizon represents debris and effects from a large, distant bolide impact, and the upper horizon represents a small, nearby bolide impact. RP WOLFE, JA (reprint author), US GEOL SURVEY,DENVER FED CTR,MS-919,BOX 25046,DENVER,CO 80225, USA. NR 24 TC 46 Z9 47 U1 2 U2 9 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD AUG 1 PY 1991 VL 352 IS 6334 BP 420 EP 423 DI 10.1038/352420a0 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FZ346 UT WOS:A1991FZ34600060 ER PT J AU VONHUENE, R SCHOLL, DW AF VONHUENE, R SCHOLL, DW TI OBSERVATIONS AT CONVERGENT MARGINS CONCERNING SEDIMENT SUBDUCTION, SUBDUCTION EROSION, AND THE GROWTH OF CONTINENTAL-CRUST SO REVIEWS OF GEOPHYSICS LA English DT Review ID BARBADOS RIDGE COMPLEX; MIDDLE AMERICA TRENCH; DE-FUCA PLATE; SOUTHERN VANCOUVER-ISLAND; MAKRAN ACCRETIONARY PRISM; DAIICHI-KASHIMA SEAMOUNT; PORE PRESSURE GENERATION; DRILLING PROGRAM LEG-112; FORE-ARC BASIN; JAPAN TRENCH AB At ocean margins where two plates converge, the oceanic plate sinks or is subducted beneath an upper one topped by a layer of terrestrial crust. This crust is constructed of continental or island arc material. The subduction process either builds juvenile masses of terrestrial crust through arc volcanism or new areas of crust through the piling up of accretionary masses (prisms) of sedimentary deposits and fragments of thicker crustal bodies scraped off the subducting lower plate. At convergent margins, terrestrial material can also bypass the accretionary prism as a result of sediment subduction, and terrestrial matter can be removed from the upper plate by processes of subduction erosion. Sediment subduction occurs where sediment remains attached to the subducting oceanic plate and underthrusts the seaward position of the upper plate's resistive buttress (backstop) of consolidated sediment and rock. Sediment subduction occurs at two types of convergent margins: type 1 margins where accretionary prisms form and type 2 margins where little net accretion takes place. At type 2 margins (approximately 19,000 km in global length), effectively all incoming sediment is subducted beneath the massif of basement or framework rocks forming the landward trench slope. At accreting or type 1 margins, sediment subduction begins at the seaward position of an active buttress of consolidated accretionary material that accumulated in front of a starting or core buttress of framework rocks. Where small-to-medium-sized prisms have formed (approximately 16,300 km), approximately 20% of the incoming sediment is skimmed off a detachment surface or decollement and frontally accreted to the active buttress. The remaining 80% subducts beneath the buttress and may either underplate older parts of the frontal body or bypass the prism entirely and underthrust the leading edge of the margin's rock framework. At margins bordered by large prisms (approximately 8,200 km), roughly 70% of the incoming trench floor section is subducted beneath the frontal accretionary body and its active buttress. In rounded figures the contemporary rate of solid-volume sediment subduction at convergent ocean margins (approximately 43,500 km) is calculated to be 1.5 km3/yr. Correcting type 1 margins for high rates of terrigenous seafloor sedimentation during the past 30 m.y. or so sets the long-term rate of sediment subduction at 1.0 km3/yr. The bulk of the subducted material is derived directly or indirectly from continental denudation. Interstitial water currently expulsed from accreted and deeply subducted sediment and recycled to the ocean basins is estimated at 0.9 km3/yr. The thinning and truncation caused by subduction erosion of the margin's framework rock and overlying sedimentary deposits have been demonstrated at many convergent margins but only off northern Japan, central Peru, and northern Chile has sufficient information been collected to determine average or long-term rates, which range from 25 to 50 km3/m.y. per kilometer of margin. A conservative long-term rate applicable to many sectors of convergent margins is 30 km3/km/m.y. If applied to the length of type 2 margins, subduction erosion removes and transports approximately 0.6 km3/yr of upper plate material to greater depths. At various places, subduction erosion also affects sectors of type 1 margins bordered by small- to medium-sized accretionary prisms (for example, Japan and Peru), thus increasing the global rate by possibly 0.5 km3/yr to a total of 1.1 km3/yr. Little information is available to assess subduction erosion at margins bordered by large accretionary prisms. Mass balance calculations allow assessments to be made of the amount of subducted sediment that bypasses the prism and underthrusts the margin's rock framework. This subcrustally subducted sediment is estimated at 0.7 km3/yr. Combined with the range of terrestrial matter removed from the margin's rock framework by subduction erosion, the global volume of subcrustally subducted material is estimated to range from 1.3 to 1.8 km3/yr. Subcrustally subducted material is either returned to the terrestrial crust by arc-related igneous processes or crustal underplating or is lost from the crust by mantle absorption. Geochemical and isotopic data support the notion that upper mantle melting returns only a small percent of the subducted material to the terrestrial crust as arc igneous rocks. Limited areal exposures of terrestrial rocks metamorphosed at deep (> 20-30 km) subcrustal pressures and temperatures imply that only a small fraction of subducted material is reattached via deep crustal underplating. Possibly, therefore much of the subducted terrestrial material is recycled to the mantle at a rate near 1.6 km3/yr, which is effectively equivalent to the commonly estimated rate at which the mantle adds juvenile igneous material to the Earth's layer of terrestrial rock. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP VONHUENE, R (reprint author), GEOMAR,W-2300 KIEL 14,GERMANY. NR 230 TC 703 Z9 704 U1 5 U2 98 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 8755-1209 J9 REV GEOPHYS JI Rev. Geophys. PD AUG PY 1991 VL 29 IS 3 BP 279 EP 316 DI 10.1029/91RG00969 PG 38 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GB095 UT WOS:A1991GB09500001 ER PT J AU CAMPBELL, DH TURK, JT SPAHR, NE AF CAMPBELL, DH TURK, JT SPAHR, NE TI RESPONSE OF NED WILSON LAKE WATERSHED, COLORADO, TO CHANGES IN ATMOSPHERIC DEPOSITION OF SULFATE SO WATER RESOURCES RESEARCH LA English DT Article ID WESTERN UNITED-STATES; ACID DEPOSITION; SULFUR; ACIDIFICATION; EMISSIONS AB The Ned Wilson Lake watershed responds directly and rapidly to changes in precipitation inputs of sulfate, which has important implications for effects of acid deposition on the aquatic system. Chemistry at three precipitation collection sites and three watershed sites (a pond, a lake, and a spring) has been monitored in and near the Flattops Wilderness Area in northwestern Colorado beginning in 1981-1983. Bulk snowpack concentration of sulfate in the watershed and volume-weighted annual mean concentration of sulfate in precipitation at two nearby sites generally decreased from 1981 to 1985, were small through 1987, and increased in 1988-1989. Changes in concentration of sulfate at the watershed sites are controlled by precipitation inputs. Responsiveness of the individual sites was dependent on their position along the hydrologic flow path. The fastest response was in the pond, which has a hydrologic residence time of less than 1 year; over 90% of the variance in concentration of sulfate in the pond was explained by changes in concentration in precipitation. The lake has a hydrologic residence time of 1 to 4 years; a regression model of the concentration of sulfate in the lake, as a function of the concentration in the lake during the previous year and the concentration in precipitation, explained 87% of the variance in concentration of sulfate in the lake. The hydrologic response time of the spring is unknown; it was not responsive to changes in concentration of sulfate in precipitation. The recent increase of sulfate concentration in precipitation and in the pond and lake is evidence for a rapid rather than a delayed response, which could not be determined when only a decreasing trend in sulfate concentration was reported in 1982-1987. Watersheds of this type are sensitive to acidification (acid-neutralizing capacity less than 60-mu-eq L-1), and these results indicate conservative behavior of sulfate. This is important in predicting effects of future changes in atmospheric deposition, which could potentially be caused by anthropogenic emissions or climatic change. RP CAMPBELL, DH (reprint author), US DEPT INTERIOR,GEOL SURVEY,DENVER FED CTR,BOX 25046,MS 415,DENVER,CO 80225, USA. NR 19 TC 15 Z9 15 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD AUG PY 1991 VL 27 IS 8 BP 2047 EP 2060 DI 10.1029/91WR01189 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FZ856 UT WOS:A1991FZ85600025 ER PT J AU LIPMAN, PW GLAZNER, AF AF LIPMAN, PW GLAZNER, AF TI INTRODUCTION TO MIDDLE TERTIARY CORDILLERAN VOLCANISM - MAGMA SOURCES AND RELATIONS TO REGIONAL TECTONICS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID WESTERN UNITED-STATES; RIO-GRANDE RIFT; NEW-MEXICO; NORTH-AMERICA; ISOTOPIC COMPOSITION; CENOZOIC VOLCANISM; CRUSTAL STRUCTURE; GRANITIC-ROCKS; MOJAVE DESERT; CENTRAL UTAH C1 UNIV N CAROLINA, DEPT GEOL, CHAPEL HILL, NC 27599 USA. US GEOL SURVEY, IGNEOUS & GEOTHERMAL PROC BRANCH, DENVER, CO 80225 USA. NR 88 TC 14 Z9 14 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13193 EP 13199 DI 10.1029/91JB01397 PG 7 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800001 ER PT J AU ARMSTRONG, RL WARD, P AF ARMSTRONG, RL WARD, P TI EVOLVING GEOGRAPHIC PATTERNS OF CENOZOIC MAGMATISM IN THE NORTH-AMERICAN CORDILLERA - THE TEMPORAL AND SPATIAL ASSOCIATION OF MAGMATISM AND METAMORPHIC CORE COMPLEXES SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Review ID WESTERN-UNITED-STATES; CENTRAL BRITISH-COLUMBIA; RIO-GRANDE RIFT; SNAKE RIVER PLAIN; NORTHWESTWARDLY YOUNGER AGE; VOLCANO-TECTONIC EVOLUTION; MENDOCINO FRACTURE-ZONE; SAN-ANDREAS TRANSFORM; SEVIER OROGENIC BELT; EAST HUMBOLDT RANGE AB Four maps are presented here that show the location and extent of magmatic fields between eastern Alaska and northern Mexico during the successive time intervals of 55-40, 40-25, 25-10, and 10-0 Ma, and four others show the distribution of metamorphic core complexes during the same Cenozoic time intervals. The maps are based on U.S. Geological Survey and Canadian Cordilleran data bases contining about 6000 isotopic dates and extensive literature review. For nearly 60 Ma the development of metamorphic core complexes has coincided with the locus of areally extensive and voluminuous intermediate-composition magmatic fields. The association is suggestive of a close link between magmatism and core complex formation, namely that magma directly and indirectly lowers the strength of the crust. Magmatism thus controls the location and timing of core complex formation. The stresses responsible may be inherited from Mesozoic crustal thickening, locally created by uplift and magmatic thickening of the crust, and imposed by the global pattern of plate motions and driving forces. Since the Miocene, rates of magmatism, extension, and core complex formation have declined. The modern Basin and Range province is not a suitable model for the situation that existed during major magmatic culminations. The singular event of early Miocene time, the merging of two large magmatic fields, extinguishing the Laramide magmatic gap, explains several disconnected observations: the hyperextension episode of the Colorado River corridor, rapid reorientation of stress patterns across much of western North America, and subsequent rapid tectonic movements in California. Magma-triggered breakup of western North America lithosphere coincided with development of the San Andreas transform system. Thermal destruction of the Laramide magmatic gap created a California "microplate" about 22 Ma ago that moved rapidly away from North America. Thus two plate tectonic processes, thermal destruction of the lithosphere "bridge" and northward growth of a transform system, interacted to produce Miocene and later tectonic patterns and events. C1 US GEOL SURVEY, MENLO PK, CA 94025 USA. RP UNIV BRITISH COLUMBIA, DEPT GEOL SCI, VANCOUVER V6T 1Z4, BC, CANADA. NR 297 TC 177 Z9 177 U1 5 U2 20 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13201 EP 13224 PG 24 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800002 ER PT J AU LEWIS, RS KIILSGAARD, TH AF LEWIS, RS KIILSGAARD, TH TI EOCENE PLUTONIC ROCKS IN SOUTH CENTRAL IDAHO SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID EARLY PRECAMBRIAN CRUST; A-TYPE GRANITES; NORTHEASTERN MINNESOTA; ZIRCON SATURATION; TRACE-ELEMENTS; GEOCHEMISTRY; ORIGIN; BATHOLITH; PETROGENESIS; MAGMAS AB Large areas previously thought to be underlain by Cretaceous granodiorite of the Idaho batholith are now known to be underlain by plutonic rocks of the Eocene Challis magmatic episode (50-44 Ma). Recent mapping conducted in south central Idaho as part of the U.S. Geological Survey's Conterminous United States Mineral Assessment Program (CUSMAP) indicates that roughly 30% of the exposed plutonic rocks are part of this younger event. The Eocene plutonic rocks are subdivided into a pink granite suite, consisting of varieties of biotite granite, and a quartz monzodiorite suite, which includes hornblende-biotite granite, granodiorite, quartz monzodiorite, diorite, and gabbro. The members of each suite form discrete epizonal stocks, and some exposures of pink granite are of batholithic size. Silica content of the quartz monzodiorite suite ranges from 48 to 70%; the rocks vary considerably in texture and mineralogy. The most mafic rocks of the quartz monzodiorite suite are cumulates. These are layered intrusive phases containing pyroxene, olivine, and plagioclase. Other mafic phases include hornblende- and pyroxene-rich diorites, which contain plagioclase feldspar as an interstitial phase and are "cumulates" in the sense that they probably represent rocks that were enriched in early formed mafic minerals by some fractionation process. Stocks of the pink granite suite are more compositionally restricted and range from 70 to 77% in SiO2 content. The quartz monzodiorite suite appears to be older than the pink granite suite, but age data are limited. Field relations, initial Sr-87/Sr-86 ratios, CaO content, and MgO/(MgO + FeO*) ratios demonstrate that the two suites are not related by fractional crystallization. Rather, the respective magmas probably originated from different sources. Large ranges in MgO, Sc, Cr, and Co content in the quartz monzodiorite suite can be explained by crystal-liquid fractionation of olivine, pyroxene, and hornblende, but variations in composition of parental magmas are also likely. Large variations of Ba content in the pink granite suite are probably a result of removal or accumulation of variable amounts of K-feldspar. Mixing between the two Eocene suites has not been extensive, but some varieties of hybrid pink granite were generated that contain mafic inclusions and have less than 72% SiO2. The pink granite has geochemical affinities with A-type granite, but unlike typical A-type granite, it is not uniformly enriched in the highly charged cations such as Zr, Nb, Y, and Ce. By analogy to other A-type granites the pink granite suite probably originated from partial melting of lower crustal rocks under high-temperature, vapor-absent conditions. C1 US GEOL SURVEY,SPOKANE,WA 99201. RP LEWIS, RS (reprint author), UNIV IDAHO,IDAHO GEOL SURVEY,MOSCOW,ID 83843, USA. NR 42 TC 15 Z9 15 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13295 EP 13311 DI 10.1029/91JB00601 PG 17 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800007 ER PT J AU CARLSON, DH FLECK, R MOYE, FJ FOX, KF AF CARLSON, DH FLECK, R MOYE, FJ FOX, KF TI GEOLOGY, GEOCHEMISTRY, AND ISOTOPIC CHARACTER OF THE COLVILLE IGNEOUS COMPLEX, NORTHEASTERN WASHINGTON SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID BRITISH-COLUMBIA; GEOCHRONOLOGY; IDAHO; ROCKS; AREA AB The Colville Igneous Complex in northeastern Washington comprises Paleocene orthogneisses and leucocratic granitic rocks and Eocene volcanic-plutonic suites which were emplaced during early Tertiary extension. The Colville Igneous Complex is divided into three components: (1) 65 +/- 4 Ma orthogneisses of the Okanogan dome or metamorphic complex and similar gneisses in the Kettle and Lincoln complexes; (2) 61-51 Ma leucocratic granitic rocks; and (3) 53-47 Ma intermediate to felsic volcanic-plutonic rocks. The leucocratic granites and younger volcanic-plutonic rocks are divided on the basis of age, geochemical and isotopic characteristics, and emplacement mechanism. The older leucocratic granites are silica rich, corundum-normative, and Sr and light rare earth element (REE) -enriched, and they form several large, discrete, compositionally zoned plutons and intrusive suites. The younger, Eocene volcanic-plutonic rocks can be divided into two suites: an older compositionally restricted (68-72 wt% SiO2), Sr-enriched, medium-K suite and a younger intermediate to felsic, high-K, calc-alkalicsuite. Sr isotopic measurements of volcanic and plutonic rock in the Colville Igneous Complex yield variable initial Sr-87/Sr-86 ratios (Sr(i)), ranging from about 0.704 to values greater than 0.710. In general, the volcanic rocks are especially variable with little or no correlation between Sr(i) and geographic location. The leucocratic granites, however, show a systematic west to east increase across the area which probably reflects an increased involvement with Precambrian crust. The variable nature of Sr(i) in the Colville Igneous Complex may also be controlled by crustal thickness and/or depth of melting. Within individual volcanic and plutonic suites, there is a crude correlation of mean Sr(i) with age. There is a systematic decrease in Sr(i) with increasing age which may reflect either a migration of the site(s) of melting or a decreased upper crustal residence time, possibly related to the onset of extension. The leucocratic granites may have formed by small degrees of partial melting in the lower crust, perhaps facilitated by thermal blanketing of an initially overthickened crust. The ascent of large bodies of leucocratic magmas may have increased the geothermal gradient which allowed for upper, more radiogenic, crust to be melted. C1 US GEOL SURVEY,ISOTOPE GEOL BRANCH,MENLO PK,CA 94025. US GEOL SURVEY,DENVER FED CTR,DIV GEOL,DENVER,CO 80225. IDAHO STATE UNIV,DEPT GEOL,POCATELLO,ID 83209. RP CARLSON, DH (reprint author), CALIF STATE UNIV SACRAMENTO,DEPT GEOL,SACRAMENTO,CA 95819, USA. NR 58 TC 7 Z9 7 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13313 EP 13333 DI 10.1029/91JB00594 PG 21 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800008 ER PT J AU CRISS, RE FLECK, RJ TAYLOR, HP AF CRISS, RE FLECK, RJ TAYLOR, HP TI TERTIARY METEORIC HYDROTHERMAL SYSTEMS AND THEIR RELATION TO ORE DEPOSITION, NORTHWESTERN UNITED-STATES AND SOUTHERN BRITISH-COLUMBIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID SAN-JUAN MOUNTAINS; ISLE-OF-SKYE; OXYGEN ISOTOPE; SKAERGAARD INTRUSION; IDAHO BATHOLITH; GRANITIC-ROCKS; IGNEOUS ROCKS; NORTHEASTERN WASHINGTON; FLUID INCLUSIONS; HYDROGEN ISOTOPE AB Tertiary meteoric hydrothermal systems have altered the rocks exposed over more than 5% of the land surface of the northwestern United States and southern British Columbia, including at least 25,000 km2 in Idaho. The systems typically involved convective circulation of fluid derived from ordinary meteoric groundwaters around crystallizing, calc-alkaline, epizonal plutons emplaced into coeval volcanic cover rocks. These individual systems had widely ranging "lifetimes" of 10(3) to 10(6) years and operated locally throughout the Cenozoic, although the most profound development of such activity occurred during Eocene time. Individual systems varied in size from a few tens of square kilometers (Yankee Fork, Idaho) or less to several thousand square kilometers (Sawtooth and Castro ring zones, Idaho) Typically, regional propylitization aacompanied the fluid circulation, although the higher-temperature alteration assemblages were developed locally, as were intense alteration effects (e.g., silicification, sericitization, etc.) near some veins and in mining districts. A significant amount, probably 25-50%, of the mineral production and potential in the region is closely related to Tertiary meteoric hydrothermal systems. Oxygen and hydrogen isotopic data clearly demonstrate the close geologic association of meteoric hydrothermal systems and mineralization in (1) the Paleocene, Cu-Zn-Pb-Mn Main Stage mineralization at Butte, Montana; (2) numerous Eocene epithermal deposits principally valued for Au and Ag but also including significant deposits of Cu, Pb, Zn, F, Sb, etc., as at Republic, Washington, and in several mining districts in the Idaho batholith and the Challis volcanic field; (3) several Eocene skarn deposits valued for W (Ima, Idaho) and Cu (Mackay, Idaho); (4) important lead-silver vein and replacement deposits of Tertiary (Bluebell, British Columbia) and of probable Cretaceous and early Tertiary age (Wood River, Idaho); (5) several potentially economic Mo-, Be-, and U-bearing Eocene "porphyry" plutons; and (6) Miocene epithermal deposits, most prominently the Au and Ag bearing veins at Silver City and DeLamar, Idaho, the Hg deposits at the McDermitt caldera, Nevada and Oregon, and at Weiser, Idaho, and Au deposits in the Western Cascade Range and Lake County, Oregon. A close spatial association has been demonstrated between ore deposits and rocks having anomalous delta-O-18 values and low delta-D values. The most important deposits are associated with relatively small (generally 5-300 km2) zones of low delta-O-18 values, and they are particularly closely linked with zones of very steep O-18/O-16 gradients in the altered rocks. These associations hold much promise for the use of delta-O-18 and delta-D contour maps in future exploration efforts. C1 CALTECH,DIV GEOL & PLANETARY SCI,PASADENA,CA 91125. US GEOL SURVEY,MENLO PK,CA 94025. RP CRISS, RE (reprint author), UNIV CALIF DAVIS,DEPT GEOL,DAVIS,CA 95616, USA. RI Barker, Shaun/A-4740-2008 NR 112 TC 27 Z9 28 U1 1 U2 13 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13335 EP 13356 DI 10.1029/91JB00640 PG 22 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800009 ER PT J AU COLUCCI, MT DUNGAN, MA FERGUSON, KM LIPMAN, PW MOORBATH, S AF COLUCCI, MT DUNGAN, MA FERGUSON, KM LIPMAN, PW MOORBATH, S TI PRECALDERA LAVAS OF THE SOUTHEAST SAN-JUAN VOLCANIC FIELD - PARENT MAGMAS AND CRUSTAL INTERACTIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID WESTERN UNITED-STATES; PLATE-TECTONIC EVOLUTION; TRACE-ELEMENT; CONTINENTAL-CRUST; CENOZOIC VOLCANISM; COLORADO; GENESIS; MANTLE; ROCKS; MOUNTAINS AB Early intermediate composition volcanic rocks of the Oligocene (circa 34-29 Ma) southeast San Juan volcanic field, southern Colorado, comprise the Conejos Formation. Conejos lavas include both high-K calc-alkaline and alkaline magma series (54-69% SiO2) ranging in composition from basaltic andesite (basaltic trachyandesite) to dacite (trachydacite). The subsequent Platoro caldera complex (29-27 Ma) was superimposed on a cluster of broadly precursory Conejos stratocones. Precaldera volcanism occurred in three pulses corresponding to three time-stratigraphic members: (1) the Horseshoe Mountain member, (2) the Rock Creek member, and (3) the Willow Mountain member. Each member exhibits distinctive phenocryst modes and incompatible trace element contents. Horseshoe Mountain lavas (hornblende-phyric) have relatively low alkali and incompatible element abundances, Rock Creek lavas (anhydrous phenocrysts) and ash-flow tuffs have the highest abundances, and Willow Mountain lavas (diverse mineralogy) are intermediate. All Conejos lavas exhibit low ratios of lead (Pb-206/Pb-204 = 17.5 to 18.2) and neodymium (epsilon-Nd = -8 to -4) isotopes and high Sr-87/Sr-86 (0.7045 to 0.7056) compared to depleted asthenospheric mantle. These values lie between those of likely mantle compositions and the isotopic composition of Proterozoic crust of the southern Rocky Mountains. Mafic lavas of the Horseshoe Mountain member have the lowest Pb and Nd isotope ratios among Conejos members but trend toward higher isotopic values with increasing degrees of differentiation. Compositions within the Rock Creek series trend toward higher Pb and lower Nd isotope ratios with increasing SiO2. Willow mountain volcanic sequences define diverse chemical-isotopic correlations. We interpret the chemical and isotopic differences observed between mafic lavas of each member to reflect derivation from compositionally distinct mantle derived parent magmas that have experienced extensive deep level crustal contamination. Chemical and isotope correlations within each member indicate Conejos magmas differentiated via staged polybaric, multiprocess evolutionary paths. Stage I occurred near the base of the crust as mantle-derived basalt evolved to basaltic andesite by the MASH mechanism. Stage II followed ascent to shallower crustal levels where basaltic andesite differentiated to more evolved compositions by combined fractionation and assimilation of heterogeneous crust. C1 SO METHODIST UNIV, DEPT GEOL SCI, DALLAS, TX 75275 USA. US GEOL SURVEY, DENVER FED CTR, DENVER, CO 80225 USA. UNIV OXFORD, DEPT EARTH SCI, OXFORD OX1 3PR, ENGLAND. NR 62 TC 28 Z9 29 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13413 EP 13434 DI 10.1029/91JB00282 PG 22 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800013 ER PT J AU DUBRAY, EA PALLISTER, JS AF DUBRAY, EA PALLISTER, JS TI AN ASH FLOW CALDERA IN CROSS-SECTION - ONGOING FIELD AND GEOCHEMICAL STUDIES OF THE MIDTERTIARY TURKEY CREEK CALDERA, CHIRICAHUA MOUNTAINS, SE ARIZONA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID TRANS-PECOS TEXAS; VOLCANIC-ROCKS; CHEMICAL CLASSIFICATION; ZIRCON SATURATION; TRACE-ELEMENTS; MAGMA CHAMBERS; NEW-MEXICO; DISCRIMINATION; EVOLUTION; COMPLEX AB Volcanic and shallow plutonic (hypabyssal) levels of the Turkey Creek caldera, located in southeast Arizona, are exposed as a consequence of uplift and erosion. The Ar-40/Ar-39 geochronology and paleomagnetic data indicate that the caldera cycle was relatively short lived and occurred at about 26.9 Ma, coincident with early phases of ductile extension in the southern Basin and Range. The caldera is a transitional calc-alkali to alkalic magmatic system and is similar to other relatively small volcanic-plutonic centers that formed after the main pulse of compressional calc-alkalic magmatism in the Cordillera. Trace element ratios and elemental distribution patterns for Turkey Creek rocks are consistent with origin in a transitional subduction to within-plate extensional setting. Field relations also suggest synextensional magmatism; regional northwest trending high-angle faults offset early caldera rocks but are buried by late moat rhyolite. Caldera collapse accompanied eruption of more than 500 km3 of high-silica rhyolite tuff (the Rhyolite Canyon Tuff). Eruption of the tuff was followed immediately by emplacement of a dacite porphyry intrusion, probably a thick laccolith, into the caldera fill and by extrusion of the dacite porphyry from ring-fracture-hosted feeders. Intracaldera tuff at the roof of the intrusion was metamorphosed and brecciated to produce low-pressure shock-metamorphic effects and was locally melted. Interpretation of the intrusion as an intracaldera laccolith readily explains a lack of floor rocks within the caldera and the absence of intracaldera equivalents of most of the outflow tuff. Intrusion of intracaldera laccoliths may represent a relatively common, though rarely recognized process within calderas. Stratigraphic relations, rare mingled rocks, and overlapping Ar-40/Ar-39 ages indicate that both high-silica rhyolite magma (Rhyolite Canyon Tuff) and dacite porphyry magma were present in the source reservoir (rhyolite above dacite) and were separated by a sharp interface. Dacite porphyry magma from beneath the interface was drawn up into and erupted from vents that previously fed ash flow eruptions; some dacite porphyry was trapped in and beneath the vents and solidified to form a ring dike at depth. Following an erosional hiatus of less-than-or-equal-to 0.3 m.y., rhyolite was again erupted, filling the caldera moat with approximately 135 km3 of mainly aphyric high-silica rhyolite. Gradational contacts with underlying densely welded tuff, relatively large volumes, planiform aspect ratios, and superliquidus temperatures suggest that some of the laminated rhyolites are rheomorphic tuff. Eruption of moat rhyolites records generation of a voluminous new batch of mainly high-silica rhyolite with a distinct geochemical signature. RP DUBRAY, EA (reprint author), US GEOL SURVEY, DENVER FED CTR MS903, DENVER, CO 80225 USA. NR 62 TC 11 Z9 11 U1 2 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13435 EP 13457 DI 10.1029/91JB00067 PG 23 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800014 ER PT J AU THOMPSON, RA JOHNSON, CM MEHNERT, HH AF THOMPSON, RA JOHNSON, CM MEHNERT, HH TI OLIGOCENE BASALTIC VOLCANISM OF THE NORTHERN RIO-GRANDE RIFT - SAN LUIS HILLS, COLORADO SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID SYSTEM MAGMATIC EVOLUTION; NEUTRON-ACTIVATION ANALYSIS; TRANS-PECOS TEXAS; NEW-MEXICO; POTASSIUM-ARGON; TRACE-ELEMENT; UNITED-STATES; FIELD; ROCKS; GEOCHEMISTRY AB The inception of the Rio Grande rift in northern New Mexico and southern Colorado was accompanied by voluminous mafic volcanism preserved in part as erosional remnants on an intrarift horst within the current axial rift graben of the San Luis Valley. Oligocene (approximately 26 Ma) volcanic rocks of the Hinsdale Formation at San Luis Hills range from 49 to 57 wt% SiO2 and include nepheline and hypersthene normative lavas. A mildly alkalic series consisting of trachybasalt, basaltic trachyandesite, and trachyandesite is volumetrically dominant, olivine tholeiites are subordinate, and xenocrystic trachyandesites containing abundant quartz and plagioclase xenocrysts occur only locally. Relative to the San Luis Hills olivine tholeiites which have La/Sm(n) approximately 2, the more alkaline series are enriched in light rare earth elements (LREE) and have La/Sm ratios that increase in the trachybasalt-basaltic trachyandesite suite (La/Sm(n) approximately 3) to xenocrystic trachyandesites that are the most LREE enriched (La/Sm(n) approximately 4). Chondrite-normalized, trace element patterns for the lavas in the San Luis Hills are similar in shape within the mildly alkaline to transitional series; they have characteristic Nb and Ta depletions and high K and Th relative to Ta, Nb, and LREE. Major and trace element constraints support a petrogenetic model of fractionation plus lower crustal assimilation for petrologic suites within the San Luis Hills rocks, although the model cannot relate lavas for the entire series to a common parent. Most mafic lavas of the San Luis Hills were evolved (Mg # < 60) and contaminated by LREE-enriched silicic partial melts of granulitic lower crust depleted in Rb, Th, and U. Pb isotopes are the most sensitive indicators of crustal contamination, whereas shifts in Nd and Sr isotope ratios are associated with large amounts of assimilation. However, relatively noncontaminated lavas can be identified and indicate at least two mantle source regions were involved. C1 UNIV WISCONSIN, DEPT GEOL & GEOPHYS, MADISON, WI 53706 USA. RP THOMPSON, RA (reprint author), US GEOL SURVEY, DENVER FED CTR, BOX 25046, DENVER, CO 80225 USA. NR 58 TC 17 Z9 17 U1 1 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13577 EP 13592 DI 10.1029/91JB00068 PG 16 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800021 ER PT J AU JOHNSON, CM THOMPSON, RA AF JOHNSON, CM THOMPSON, RA TI ISOTOPIC COMPOSITION OF OLIGOCENE MAFIC VOLCANIC-ROCKS IN THE NORTHERN RIO-GRANDE RIFT - EVIDENCE FOR CONTRIBUTIONS OF ANCIENT INTRAPLATE AND SUBDUCTION MAGMATISM TO EVOLUTION OF THE LITHOSPHERE SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Review ID LOWER CRUSTAL XENOLITHS; SOUTHWESTERN UNITED-STATES; GRANULITE-FACIES METAMORPHISM; MIDTERTIARY FELSIC VOLCANICS; MANTLE-DERIVED XENOLITHS; WEST-CENTRAL COLORADO; NEW-MEXICO; IGNEOUS ROCKS; PB-ISOTOPE; TRACE-ELEMENT AB Mafic lavas erupted during initiation of regional extension at 26 Ma in the northern Rio Grande rift were derived from at least two isotopically distinct mantle sources. One is characterized by Sr-87/Sr-86 = 0.70495, epsilon-Nd = -4, Pb-206/Pb-204 = 18.2, and the other by Sr-87/Sr-86 = 0.7044, epsilon-Nd = 0, Pb-206/Pb-204 = 18.2. The low-epsilon-Nd value source (MANTLE 1) is interpreted to largely reflect the isotopic compositions of the lithospheric mantle in the region. Isotopic compositions of Cenozoic mafic lavas and Proterozoic rocks are used to constrain models for evolution of the lithosphere. The low epsilon-Nd values of the MANTLE 1 component were probably produced by evolution of a light rate earth element-enriched upper mantle or input of low-epsilon-Nd material during development of the lithosphere in the Early Proterozoic. The epsilon-Nd values and Pb-206/Pb-204 ratios in evolved rocks are as low as -7 and 17.3, respectively, indicating interaction with lower crust that had epsilon-Nd less-than-or-equal-to 12 and Pb-206/Pb-204 less-than-or-equal-to 17.0. Initial Sr-87/Sr-86 ratios both increase and decrease slightly in evolved rocks, indicating interaction with lower crust that had Sr isotope ratios that were generally similar to those of the mantle. The epsilon-Nd value of the modern lithospheric mantle beneath the northern Rio Grande rift is > 18 units lower than the projected modern values of the asthenospheric mantle from which the Proterozoic crust was originally derived. The higher-epsilon-Nd value source (MANTLE 2) may reflect mixing of asthenosphere and lithosphere components. The mantle source for most late Cenozoic mafic lavas in the northern Rio Grande rift region lies at Pb-207/Pb-204 ratios that are significantly higher than the Pb-206/Pb-204 - Pb-207/Pb-204 array defined by crust in the region. Although the crustal array is also displaced to higher Pb-207/Pb-204 ratios as compared to the northern hemisphere oceanic mantle array, indicating incorporation of Archean Pb during crust formation, the still higher Pb-207/Pb-204 ratios in the Rio Grande rift mantle source is interpreted to reflect continued input of Archean Pb into the developing Early Proterozoic lithospheric mantle after crust formation. These relations are strong evidence that the lithosphere became stabilized shortly after the major crust formation events in the Early Proterozoic. C1 US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. RP JOHNSON, CM (reprint author), UNIV WISCONSIN,DEPT GEOL & GEOPHYS,MADISON,WI 53706, USA. NR 132 TC 32 Z9 32 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13593 EP 13608 DI 10.1029/91JB00342 PG 16 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800022 ER PT J AU GLAZNER, AF FARMER, GL HUGHES, WT WOODEN, JL PICKTHORN, W AF GLAZNER, AF FARMER, GL HUGHES, WT WOODEN, JL PICKTHORN, W TI CONTAMINATION OF BASALTIC MAGMA BY MAFIC CRUST AT AMBOY AND PISGAH CRATERS, MOJAVE DESERT, CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID WESTERN UNITED-STATES; SOUTHERN CALIFORNIA; ISOTOPIC VARIATIONS; VOLCANIC-ROCKS; RANGE PROVINCE; MANTLE; ARIZONA; BASIN; EVOLUTION; EXTENSION AB Quaternary alkali basalts from Pisgah Crater and Amboy Crater in southern California exhibit unusual chemical and isotopic variations which probably result from assimilation of mafic crust. Although lavas from both volcanoes are alkali basalts and hawaiites with isotopic and chemical characteristics that are similar to ocean island basalts (OIB) (e.g., epsilon-Nd = 2.6 - 5.9, Sr-87/Sr-86 = 0.7038 - 0.7049, Hf/Ba = 0.014 - 0.017), they display highly correlated and unusual variations in their chemical and isotopic compositions. At each volcano, MgO decreased during the eruptive sequence from almost-equal-to 8.5 wt % to almost-equal-to 4.5 wt %. Incompatible elements are positively correlated with MgO and therefore also decreased during the eruptive sequence. Nd, Sr, and Pb isotope ratios correlate strongly with MgO. Compositional and isotopic data cannot be explained by any combination of closed-system fractionation, partial melting of the mantle, or silicic contamination. These data indicate that the basalts represent mixing between a high-MgO, high-epsilon-Nd component, common to both Pisgah and Amboy craters, with lower-MgO and -epsilon-Nd components that are unique to each center. The high-MgO component most likely is a primitive mantle-derived magma, based in part on its similarity to nearby xenolith-bearing Quaternary basalts. The low-MgO components are interpreted to be partial melts of mafic crust. If our model is correct, then both volcanoes evolved from eruption of nearly pure mantle melts early in their history to eruption of nearly pure remelted mafic crust late in their history. The crustal source could not have been underplated Mesozoic or younger oceanic crust, but its age is otherwise unconstrained; nearby Mesozoic gabbros and Proterozoic diabases have appropriate isotopic compositions. The basalt data provide no evidence that ancient enriched lithospheric mantle currently underlies the Mojave Desert. If such mantle was present at any time beneath this region, it must have been removed during one or more of the many tectonic events that affected the Mojave Desert during the Phanerozoic. Regional variability of isotope ratios in basalts is commonly interpreted to reflect variability of the underlying mantle. Data from this study raise the possibility that some of this variability may result from cryptic contamination of OIB-like basalts by mafic crust. C1 UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309. UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. OPERAT TECHNOL CORP,MATHER AFB,CA 95655. US GEOL SURVEY,MENLO PK,CA 94025. RP GLAZNER, AF (reprint author), UNIV N CAROLINA,DEPT GEOL,CB 3315,CHAPEL HILL,NC 27599, USA. NR 74 TC 50 Z9 52 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 30 PY 1991 VL 96 IS B8 BP 13673 EP 13691 DI 10.1029/91JB00175 PG 19 WC Geosciences, Multidisciplinary SC Geology GA FY298 UT WOS:A1991FY29800026 ER PT J AU GRIFFITHS, RW THORNLEY, S EDSALL, TA AF GRIFFITHS, RW THORNLEY, S EDSALL, TA TI LIMNOLOGICAL ASPECTS OF THE ST-CLAIR RIVER SO HYDROBIOLOGIA LA English DT Article DE ENVIRONMENTAL IMPACT; MACROINVERTEBRATES; MACROPHYTES; FISHES; WATER QUALITY; GREAT LAKES SYSTEM ID MACROPHYTE COMMUNITIES; DETROIT RIVERS; LAKES; HURON; ERIE; CONTAMINANTS; BIOMASS; ONTARIO; HABITAT; GROWTH AB The St. Clair River is a major navigable waterway transporting water southwards for 63 km from Lake Huron to Lake St. Clair at an average flow of 5 100 m3 s-1. Water entering the river is low in suspended solids, organic carbon, phosphorus and nitrates, typical of clear, oligotrophic waters. In contrast to many large rivers, dissolved and colloidal solids account for 90 to 95 percent of the total solids load transported by the river, giving the river a turquoise colour common of glacial meltwater streams. The river supports a diverse floral and faunal community that includes 20 taxa of submergent macroflora, at least 300 benthic macroinvertebrates and 83 fishes. A number of exotic (European) species, including 3 plants, 4 molluscs and 11 fishes, occur in the river with the macroalga, Nitellopsis obtusa, zebra mussel (Dreissena polymorphora), Asian clam (Corbicula fluminea), and white perch (Morone americana) being the most recent invaders. Production is estimated to be 200 g m-2 a-1 ash-free dry mass for submergent macrophytes and periphyton, 7 g for macroinvertebrates and 5 g for fishes. The river also supports a variety of water-oriented recreational activities, is a source of municipal and industrial water, a receiver of municipal and industrial wastes, and a shipping corridor. Industrial discharges have adversely affected aquatic life, particularly in the nearshore areas along the Canadian shoreline south of Sarnia, Ontario. In addition, channel dredging and shoreline modifications (bulk-heading and backfilling) have destroyed large areas of valuable habitat in the main channel and along the shoreline. Improvements in the nearshore benthic macroinvertebrate community of the river over the past 20 years show that the river will respond to reductions in contaminants loadings. C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105. RP GRIFFITHS, RW (reprint author), MINIST ENVIRONM,SW REG,WATER RESOURCES ASSESSMENT UNIT,LONDON N6E 1V3,ONTARIO,CANADA. NR 62 TC 8 Z9 8 U1 1 U2 17 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 97 EP 123 DI 10.1007/BF00024749 PG 27 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100007 ER PT J AU FRENCH, JRP SCHLOESSER, DW AF FRENCH, JRP SCHLOESSER, DW TI GROWTH AND OVERWINTER SURVIVAL OF THE ASIATIC CLAM, CORBICULA-FLUMINEA, IN THE ST-CLAIR RIVER, MICHIGAN SO HYDROBIOLOGIA LA English DT Article DE CORBICULIDAE; TEMPERATURES; POPULATION DYNAMICS; DOWNSTREAM DISTRIBUTION ID LAKE ERIE AB We report the discovery in April 1986 of the first population of the Asiatic clam, Corbicula fluminea, known to occupy a lotic environment in the Laurentian Great Lakes system. This population occupied a 3.8 km long sandy shoal in the discharge plume of a steam-electric power plant on the St. Clair River (Michigan), the outflow of Lake Huron. Samples collected April 1986 to April 1987 revealed the growth of one-year-old Corbicula (1985 cohort) began after mid-May and ended by mid-November, while water temperatures were higher than 9-degrees-C. Maximum growth (0.78 mm wk-1) occurred between mid-August and mid-September, while water temperatures were about 16-23-degrees-C. We recorded a substantial overwinter mortality of the 1986 cohort, but not the 1985 cohort; this was particularly evident at sampling locations more remote from the heated discharge of the power plant, suggesting low water temperature was the major mortality agent. The available information suggests low water temperature in the St. Clair River may limit the success of Corbicula in the river, including portions of populations inhabiting thermal plumes, by reducing growth, delaying the onset of sexual maturity and reproduction, and by causing heavy overwinter mortality in the first year of life. RP FRENCH, JRP (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,1451 GREEN RD,ANN ARBOR,MI 48105, USA. NR 19 TC 22 Z9 22 U1 1 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 165 EP 170 DI 10.1007/BF00024753 PG 6 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100011 ER PT J AU MANNY, BA KENAGA, D AF MANNY, BA KENAGA, D TI THE DETROIT RIVER - EFFECTS OF CONTAMINANTS AND HUMAN ACTIVITIES ON AQUATIC PLANTS AND ANIMALS AND THEIR HABITATS SO HYDROBIOLOGIA LA English DT Article DE WATER; SEDIMENTS; OIL; HEAVY METALS; PCBS; PLANKTON; CLAMS; FISH; AND BIRDS ID LAKE ST-CLAIR; ORGANOCHLORINE CONTAMINANTS; HEAVY-METALS; SEDIMENTS; WATER; ERIE; TOXICITY; MERCURY; TRACE; CLAMS AB Despite extensive urbanization of its watershed, the Detroit River still supports diverse fish and wildlife populations. Conflicting uses of the river for waste disposal, water withdrawals, shipping, recreation, and fishing require innovative management. Chemicals added by man to the Detroit River have adversely affected the health and habitats of the river's plants and animals. In 1985, as part of an Upper Great Lakes Connecting Channels Study sponsored by Environment Canada and the U.S. Environmental Protection Agency, researchers exposed healthy bacteria, plankton, benthic macroinvertebrates, fish, and birds to Detroit River sediments and sediment porewater. Negative impacts included genetic mutations in bacteria; death of macroinvertebrates; accumulation of contaminants in insects, clams, fishes, and ducks; and tumor formation in fish. Field surveys showed areas of the river bottom that were otherwise suitable for habitation by a variety of plants and animals were contaminated with chlorinated hydrocarbons and heavy metals and occupied only by pollution-tolerant worms. Destruction of shoreline wetlands and disposal of sewage and toxic substances in the Detroit River have reduced habitat and conflict with basic biological processes, including the sustained production of fish and wildlife. Current regulations do not adequately control pollution loadings. However, remedial actions are being formulated by the U.S. and Canada to restore degraded benthic habitats and eliminate discharges of toxic contaminants into the Detroit River. RP MANNY, BA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105, USA. NR 64 TC 22 Z9 22 U1 5 U2 30 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 269 EP 279 DI 10.1007/BF00024760 PG 11 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100018 ER PT J AU NICHOLS, SJ MANNY, BA SCHLOESSER, DW EDSALL, TA AF NICHOLS, SJ MANNY, BA SCHLOESSER, DW EDSALL, TA TI HEAVY-METAL CONTAMINATION OF SEDIMENTS IN THE UPPER CONNECTING CHANNELS OF THE GREAT-LAKES SO HYDROBIOLOGIA LA English DT Article DE METALS; SEDIMENT CONTAMINATION; DEPOSITION ZONES; RIVERS ID DETROIT RIVER SEDIMENTS AB In 1985, sampling at 250 stations throughout the St. Marys, St. Clair, and Detroit rivers and Lake St. Clair - the connecting channels of the upper Great Lakes - revealed widespread metal contamination of the sediments. Concentrations of cadmium, chromium, copper, lead, mercury, nickel, and zinc each exceeded U.S. Environmental Protection Agency sediment pollution guidelines at one or more stations throughout the study area. Sediments were polluted more frequently by copper, nickel, zinc, and lead than by cadmium, chromium, or mercury. Sediments with the highest concentrations of metals were found (in descending order) in the Detroit River, the St. Marys River, the St. Clair River, and Lake St. Clair. Although metal contamination of sediments was most common and sediment concentrations of metals were generally highest near industrial areas, substantial contamination of sediments by metals was present in sediment deposition areas up to 60 km from any known source of pollution. RP NICHOLS, SJ (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,1451 GREEN RD,ANN ARBOR,MI 48105, USA. NR 17 TC 21 Z9 21 U1 0 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 307 EP 315 DI 10.1007/BF00024763 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100021 ER PT J AU MANNY, BA NICHOLS, SJ SCHLOESSER, DW AF MANNY, BA NICHOLS, SJ SCHLOESSER, DW TI HEAVY-METALS IN AQUATIC MACROPHYTES DRIFTING IN A LARGE RIVER SO HYDROBIOLOGIA LA English DT Article DE VASCULAR PLANTS; CADMIUM; NICKEL; COPPER; ZINC; LEAD; DETROIT RIVER; LAKE ERIE ID DETROIT RIVER; LAKE HURON; ST-CLAIR; SAGINAW BAY; SEDIMENTS; PLANTS; TRANSPORT; ACCUMULATION; MERCURY; SYSTEM AB Macrophytes drifting throughout the water column in the Detroit River were collected monthly from May to October 1985 to estimate the quantities of heavy metals being transported to Lake Erie by the plants. Most macrophytes (80-92% by weight) drifted at the water surface. Live submersed macrophytes made up the bulk of each sample. The most widely distributed submersed macrophyte in the river, American wildcelery (Vallisneria americana), occurred most frequently in the drift. A total of 151 tonnes (ash-free dry weight) of macrophytes drifted out of the Detroit River from May to October. The drift was greatest (37 tonnes) in May. Concentrations of heavy metals were significantly higher in macrophytes drifting in the river than in those growing elsewhere in unpolluted waters. Annually, a maximum of 2 796 kg (eight heavy metals combined) were transported into Lake Erie by drifting macrophytes. The enrichment of all metals was remarkably high (range: 4 000 x to 161 000 x) in macrophytes, relative to their concentration in water of the Detroit River. Detroit River macrophytes are thus a source of contaminated food for animals in the river and in Lake Erie. RP MANNY, BA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105, USA. NR 62 TC 26 Z9 27 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 333 EP 344 DI 10.1007/BF00024766 PG 12 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100024 ER PT J AU SCHLOESSER, DW EDSALL, TA MANNY, BA NICHOLS, SJ AF SCHLOESSER, DW EDSALL, TA MANNY, BA NICHOLS, SJ TI DISTRIBUTION OF HEXAGENIA NYMPHS AND VISIBLE OIL IN SEDIMENTS OF THE UPPER GREAT-LAKES CONNECTING CHANNELS SO HYDROBIOLOGIA LA English DT Article DE HEXAGENIA; OIL; GREAT LAKES; CHANNELS; POLLUTION ID DETROIT; RIVER AB As part of the study of the Upper Great Lakes Connecting Channels sponsored by the U.S. Environmental Protection Agency, the U.S. Fish and Wildlife Service examined the occurrence of Hexagenia nymphs and visible oil in sediments at 250 stations throughout the St. Marys River and the St. Clair-Detroit River system from May 14 to June 11, 1985. The mean density of Hexagenia nymphs per square meter averaged 194 for the total study area, 224 in the St. Marys River, 117 in the St. Clair River, 279 in Lake St. Clair, and 94 in the Detroit River. The maximum density of nymphs ranged from 1,081 to 1,164 m-2 in the three rivers and was 3,099 m-2 in Lake St. Clair. A comparison of nymph density at 46 stations where oil was observed in sediments physically suitable for nymphs showed that densities were lower in oiled sediments (61 m-2) than in sediments without oil (224 m-2). Densities of nymphs were relatively high at only four stations where oil was observed in sediments. In general, oiled sediments and low densities of nymphs occurred together downstream from industrial and municipal discharges. RP US FISH & WILDLIFE SERV, NATL FISHERIES RES CTR GREAT LAKES, ANN ARBOR, MI 48105 USA. NR 36 TC 16 Z9 16 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0018-8158 EI 1573-5117 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 345 EP 352 DI 10.1007/BF00024767 PG 8 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100025 ER PT J AU EDSALL, TA MANNY, BA SCHLOESSER, DW NICHOLS, SJ FRANK, AM AF EDSALL, TA MANNY, BA SCHLOESSER, DW NICHOLS, SJ FRANK, AM TI PRODUCTION OF HEXAGENIA-LIMBATA NYMPHS IN CONTAMINATED SEDIMENTS IN THE UPPER GREAT-LAKES CONNECTING CHANNELS SO HYDROBIOLOGIA LA English DT Article DE GREAT LAKES; BURROWING MAYFLY; PRODUCTION; CONTAMINATED SEDIMENTS; HEXAGENIA ID ESTIMATING SECONDARY PRODUCTION; HYNES METHOD; TOXICITY AB In April through October 1986, we sampled sediments and populations of nymphs of the burrowing mayfly, Hexagenia limbata (Serville), at 11 locations throughout the connecting channels of the upper Great Lakes, to determine if sediment contaminants adversely affected nymph production. Production over this period was high (980 to 9231 mg dry wt m-2) at the five locations where measured sediment levels of oil, cyanide, and six metals were below the threshold criteria of the U.S. Environmental Protection Agency and the Ontario Ministry of Environment for contaminated or polluted sediments, and also where the criterion for visible oil given in the Water Quality Agreement between the U.S.A. and Canada for connecting waters of the Great Lakes was not exceeded. At the other six locations where sediments were polluted, production was markedly lower (359 to 872 mg dry wt m-2). This finding is significant because it indicates that existing sediment quality criteria can be applied to protect H. limbata from oil, cyanide, and metals in the Great Lakes and connecting channels where the species fulfills a major role in secondary production and trophic transfer of energy. RP EDSALL, TA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105, USA. NR 35 TC 17 Z9 17 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP 353 EP 361 DI 10.1007/BF00024768 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100026 ER PT J AU MUNAWAR, M EDSALL, T AF MUNAWAR, M EDSALL, T TI ENVIRONMENTAL ASSESSMENT AND HABITAT EVALUATION OF THE UPPER GREAT-LAKES CONNECTING CHANNELS - PREFACE SO HYDROBIOLOGIA LA English DT Editorial Material DE UPPER GREAT LAKES CONNECTING CHANNELS; ENVIRONMENTAL ASSESSMENT C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105. RP MUNAWAR, M (reprint author), FISHERIES & OCEANS CANADA,CANADA CTR INLAND WATERS,GREAT LAKES LAB FISHERIES & AQUAT SCI,BURLINGTON L7R 4A6,ONTARIO,CANADA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 26 PY 1991 VL 219 BP R9 EP R13 DI 10.1007/BF00024744 PG 5 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GK031 UT WOS:A1991GK03100002 ER PT J AU PERRY, SA PERRY, WB AF PERRY, SA PERRY, WB TI ORGANIC-CARBON DYNAMICS IN 2 REGULATED RIVERS IN NORTHWESTERN MONTANA, USA SO HYDROBIOLOGIA LA English DT Article DE DISSOLVED ORGANIC CARBON; PARTICULATE ORGANIC CARBON; ORGANIC MATTER TRANSPORT; REGULATED RIVERS ID FREE-FLOWING RIVER; MATTER TRANSPORT; PARTICULATE; QUALITY; SESTON; IMPOUNDMENT; DOWNSTREAM; CATCHMENTS; WATERSHEDS; VIRGINIA AB We studied the transport of particulate organic carbon (POC) and dissolved organic carbon (DOC) in two regulated rivers during minimum and increasing discharges. Mean annual concentrations of total POC, measured monthly during conditions of minimum discharge from the dams, were twice as high at a station below a dam with a selective withdrawal system on the Kootenai River (KR, 0.15 mg l-1), as at a station below a dam with hypolimnetic water releases on the Flathead River (FR, 0.07 mg l-1). Annual mean concentrations of DOC were similar below both dams (1.62 mg l-1 FR; 1.71 KR). The percentage of POC in four size fractions differed in regulated and unregulated reaches of each river system; the smallest size fraction (0.45-10-mu-m) constituted a larger percentage of the total POC at the stations below the dams (50-93%), because POC in larger size classes had settled out in the reservoir. The three largest size fractions (10-1000-mu-m) comprised a larger percentage of the total POC when samples were taken during conditions of full discharge from the dam. We measured large increases in all size classes of POC in samples collected during increasing discharges in a regulated reach, reflecting the component of sloughed periphyton and resuspended organic matter that were added during periods of hydropower generation at the dam. Seston (355-mu-m to 1 cm) collected in nets increased dramatically during increasing flows; concentrations of particulate organic matter (POM) in samples collected two and three hours after water levels began to rise were 572 and 1 440 times higher than those collected during minimum discharge at the dam. C1 W VIRGINIA UNIV,DIV FORESTRY,MORGANTOWN,WV 26506. RP PERRY, SA (reprint author), W VIRGINIA UNIV,US FISH & WILDLIFE SERV,MORGANTOWN,WV 26506, USA. NR 42 TC 8 Z9 8 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUL 19 PY 1991 VL 218 IS 3 BP 193 EP 203 DI 10.1007/BF00038835 PG 11 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA GE390 UT WOS:A1991GE39000002 ER PT J AU NOWAK, RM AF NOWAK, RM TI SPECIES HYBRIDIZATION AND PROTECTION OF ENDANGERED ANIMALS SO SCIENCE LA English DT Letter RP NOWAK, RM (reprint author), US FISH & WILDLIFE SERV,OFF SCI AUTHOR,MAIL STOP 725,ARLINGTON SQ,WASHINGTON,DC 20240, USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD JUL 19 PY 1991 VL 253 IS 5017 BP 250 EP 251 DI 10.1126/science.253.5017.250-a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FX224 UT WOS:A1991FX22400003 PM 17794668 ER PT J AU MASTERS, CD ROOT, DH ATTANASI, ED AF MASTERS, CD ROOT, DH ATTANASI, ED TI RESOURCE CONSTRAINTS IN PETROLEUM PRODUCTION POTENTIAL SO SCIENCE LA English DT Article ID OIL AB Geologic reasons indicate that the dominant position of the Middle East as a source of conventional petroleum will not be changed by new discoveries elsewhere. The share of world crude oil production coming from the Middle East could increase, within 10 to 20 years, to exceed 50 percent, under even modest increases in world consumption. Nonconventional resources of oil exist in large quantities, but because of their low production rates they can at best only mitigate extant trends. Increased production of natural gas outside the United States, however, offers an opportunity for geographically diversified energy supplies in the near future. RP MASTERS, CD (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 33 TC 24 Z9 24 U1 2 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD JUL 12 PY 1991 VL 253 IS 5016 BP 146 EP 152 DI 10.1126/science.253.5016.146 PG 7 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FW160 UT WOS:A1991FW16000024 PM 17779130 ER PT J AU KISSLINGER, C JONES, LM AF KISSLINGER, C JONES, LM TI PROPERTIES OF AFTERSHOCK SEQUENCES IN SOUTHERN CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID IMPERIAL-VALLEY; HEAT-FLOW; EARTHQUAKE SEQUENCE; OCTOBER 15; JULY 1986; FAULT; SEISMICITY; SWARM AB The temporal behavior of 39 aftershock sequences in southern California, 1933-1988, was modeled by the modified Omori relation. Minimum magnitudes for completeness of each sequence catalog were determined, and the maximum likelihood estimates of the parameters K, p, and c, with the standard errors on each, were determined by the Ogata algorithm. The b value of each sequence was also calculated. Many of the active faults in the region, both strike slip and thrust, were sampled. The p values were graded in terms of the size of the standard error relative to the p value itself. Most of the sequences were modeled well by the Omori relation. Many of the sequences had p values close to the mean of the whole data set, 1.11 +/- 0.25, but values significantly different from the mean, as low as 0.7 and as high as 1.8, exist. No correlation of p with either the b value of the sequence or the mainshock magnitude was found. The results suggest a direct correlation of p values is with surface heat flow, with high values in the Salton Trough (high heat flow) and one low value in the San Bernardino Mountains and on the edge of the Ventura Basin (both low heat flow). The large fraction of the sequences with p values near the mean are at locations where the heat flow is near the regional mean, 74 mW/m2. If the hypothesis that aftershock decay rate is controlled by temperature at depth is valid, the effects of other factors such as heterogeneity of the fault zone properties are superimposed on the background rate determined by temperature. Surface heat flow is taken as an indicator of crustal temperature at hypocentral depths, but the effects on heat flow of convective heat transport and variations in near-surface thermal conductivity invalidate any simple association of local variations in heat flow with details of the subsurface temperature distribution. The interpretation is that higher temperatures in the aftershock source volume caused shortened stress relaxation times in the fault zone materials, leading to a faster decay rate (higher p value). In 1967, Mogi proposed such a relation on the basis of Japanese data. Seismic velocity distributions published for southern California generally support the hypothesis, with low velocities (higher temperatures) corresponding to high p values, and vice-versa. C1 US GEOL SURVEY,PASADENA,CA 91106. RP KISSLINGER, C (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,CAMPUS BOX 216,BOULDER,CO 80309, USA. NR 48 TC 137 Z9 147 U1 4 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 11947 EP 11958 DI 10.1029/91JB01200 PG 12 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900022 ER PT J AU AGNEW, DC JONES, LM AF AGNEW, DC JONES, LM TI PREDICTION PROBABILITIES FROM FORESHOCKS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID EARTHQUAKE PREDICTION; SAN-ANDREAS; CALIFORNIA; PRECURSORS; RUPTURE; HAZARD; FAULTS AB When any earthquake occurs, the possibility that it might be a foreshock increases the probability that a larger earthquake will occur nearby within the next few days. Clearly, the probability of a very large earthquake ought to be higher if the candidate foreshock were on or near a fault capable of producing that very large mainshock, especially if the fault is towards the end of its seismic cycle. We derive an expression for the probability of a major earthquake characteristic to a particular fault segment, given the occurrence of a potential foreshock near the fault. To evaluate this expression, we need: (1) the rate of background seismic activity in the area, (2) the long-term probability of a large earthquake on the fault, and (3) the rate at which foreshocks precede large earthquakes, as a function of time, magnitude, and spatial location. For this last function we assume the average properties of foreshocks to moderate earthquakes in California: (1) the rate of mainshock occurrence after foreshocks decays roughly as t-1, so that most foreshocks are within three days of their mainshock, (2) foreshocks and mainshocks occur within 10 km of each other, and (3) the fraction of mainshocks with foreshocks increases linearly as the magnitude threshold for foreshocks decreases, with 50% of the mainshocks having foreshocks with magnitudes within three units of the mainshock magnitude (within three days). We apply our results to the San Andreas, Hayward, San Jacinto, and Imperial faults, using the probabilities of large earthquakes from the report of the Working Group on California Earthquake Probabilities (1988). The magnitude of candidate event required to produce a 1% probability of a large earthquake on the San Andreas fault within three days ranges from a high of 5.3 for the segment in San Gorgonio Pass to a low of 3.6 for the Carrizo Plain. C1 US GEOL SURVEY,PASADENA,CA 91106. RP AGNEW, DC (reprint author), UNIV CALIF SAN DIEGO,INST GEOPHYS & PLANETARY PHYS,LA JOLLA,CA 92093, USA. OI Agnew, Duncan/0000-0002-2360-7783 NR 27 TC 58 Z9 60 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 11959 EP 11971 DI 10.1029/91JB00191 PG 13 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900023 ER PT J AU BOWMAN, JR DEWEY, JW AF BOWMAN, JR DEWEY, JW TI RELOCATION OF TELESEISMICALLY RECORDED EARTHQUAKES NEAR TENNANT CREEK, AUSTRALIA - IMPLICATIONS FOR MIDPLATE SEISMOGENESIS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID INTRAPLATE EARTHQUAKES; JANUARY 22; FAULT; AFTERSHOCKS; SEQUENCE; STRESS; ARRAY AB The three M(S) > 6 Tennant Creek, Australia, earthquakes of January 22, 1988, were preceded by small and moderate earthquakes in 1986 and 1987. We have used the method of joint hypocenter determination to estimate the positions of teleseismically recorded 1986-1987 earthquakes, the 1988 main shocks, and aftershocks with respect to a system of surface fault scarps. The 1986-1987 shocks and the 1988 main shocks nucleated near the center of the zone of surface scarps, where fault-segment boundaries at depth are implied by complexities in the distribution of scarps at the surface. This suggests that the fault segments that ruptured in 1988 were already in existence in 1986-1987, which is consistent with the hypothesis that strong midplate earthquakes occur on preexisting faults. The redetermined 1986-1987 hypocenters are, however, also consistent with the hypothesis that midplate seismicity is localized by stress concentration due to bulk rheological heterogeneity of the crust, because they are situated on a regionally prominent gravity anomaly. The teleseismically recorded seismicity of the Tennant Creek region prior to the 1988 main shocks has the temporal pattern of a swarm followed by a lull. The concentration of swarm earthquakes between two scarps is consistent with models in which precursory-swarm earthquakes correspond to faulting that is spatially distinct from the site of primary main-shock faulting. The time interval between swarm and main shocks is similar to intervals between intermediate-term precursory swarms and main shocks in regions that have much higher rates of tectonic loading; this similarity suggests that the time intervals between precursory swarms and subsequent main shocks are not strongly influenced by the rate of tectonic loading, but are determined primarily by time dependence of the failure process. The spatial distribution of teleseismically recorded aftershocks is in most respects like that of aftershocks recorded by a local network of portable stations in the half year following the main shocks. The set of teleseismically recorded aftershocks, like the set of locally recorded aftershocks, includes some events that occurred well away from the causative faults of the main shocks. At the length scale of the 1988 main-shock rupture, the distribution of aftershocks occurring more than one year after the main shocks is not representative of the distribution of earlier aftershocks. C1 US GEOL SURVEY,DENVER FED CTR,NATL EARTHQUAKE INFORMAT CTR,DENVER,CO 80225. RP BOWMAN, JR (reprint author), AUSTRALIAN NATL UNIV,RES SCH EARTH SCI,GPO BOX 4,CANBERRA,ACT 2601,AUSTRALIA. NR 25 TC 7 Z9 7 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 11973 EP 11979 DI 10.1029/91JB00923 PG 7 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900024 ER PT J AU VERNON, FL FLETCHER, J CARROLL, L CHAVE, A SEMBERA, E AF VERNON, FL FLETCHER, J CARROLL, L CHAVE, A SEMBERA, E TI COHERENCE OF SEISMIC BODY WAVES FROM LOCAL EVENTS AS MEASURED BY A SMALL-APERTURE ARRAY SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID LATERAL VELOCITY VARIATIONS; INCIDENT SH-WAVES; SOUTHERN-CALIFORNIA; GROUND MOTION; CRUST; SCATTERING; ANZA AB Eight local earthquakes were recorded during the operation of a small-aperture seismic array at Pinyon Flat, California. The site was chosen for its homogeneous granitic geology and its planar topography. Amplitude spectral ratios for the same signal measured at different stations had average values of less than 2 and maximum values of 7. Magnitude-squared coherences were estimated for all station pairs. These estimates were highest for the P wave arrivals on the vertical component and lowest for the P wave recorded on the transverse component. At 500 m station separation the P and S waves were incoherent above 15 Hz and 10 Hz, respectively. Coherence for both the P and S waves decrease as frequency increases and as distance increases. The coherence of signals from borehole sensors located at 300 and 150 m depth displays higher average coherence than equally spaced sites located on the surface. The results here suggest that even for sites that appear to be very similar, that is, those which are located on a planar surface within a few meters of granite bedrock, the measured seismic wavefield can be distorted substantially over scale lengths of 500 m. Coherence properties were calculated from synthetic seismograms which were computed for velocity models with exponential and self similar distribution perturbations. Standard deviations of 10% are not sufficient for the random velocity distributions to approximate the results from the small-aperture array. C1 US GEOL SURVEY,OFF EARTHQUAKES VOLCANOES & ENGN,MENLO PK,CA 94025. AT&T BELL LABS,1E444,MURRAY HILL,NJ 07974. RP VERNON, FL (reprint author), UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,INST GEOPHYS & PLANETARY PHYS,A-025,LA JOLLA,CA 92093, USA. NR 33 TC 42 Z9 42 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 11981 EP 11996 DI 10.1029/91JB00193 PG 16 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900025 ER PT J AU HENNET, CG LUETGERT, JH PHINNEY, RA AF HENNET, CG LUETGERT, JH PHINNEY, RA TI THE CRUSTAL STRUCTURE IN CENTRAL MAINE FROM COHERENCY PROCESSED REFRACTION DATA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID GRENVILLE BASEMENT BENEATH; LOWER CONTINENTAL-CRUST; NORTHERN APPALACHIANS; SEISMIC VELOCITIES; COASTAL MAINE; QUEBEC-MAINE; REFLECTION; TERRANES; ROCKS AB In 1984, the U.S. Geological Surcvey and the Canadian Department of Energy, Mines and Resources conducted an extensive seismic refraction experiment, the Quebec-Maine Transect Project. As part of this project, a 180-km-long seismic refraction profile was recorded along the axis of the Central Maine synclinorium. High near-surface velocities of 6.0-6.2 km/s made a conventional refraction analysis (including first arrivals) uninformative below about 10 km. Peak signal frequencies around 30 Hz, recorded at all offsets, and a trace spacing of 800 m led to severe spatial aliasing effects for secondary arrivals on the record sections. To allow a reliable deep structural interpretation, a coherency processing technique was applied to the data to enhance phase coherent secondary arrivals. In addition, interpretation of a coincident wide-angle reflection study provided constraints on the deep crustal velocities and structure. The crust beneath the Central Maine synclinorium can be described by three major structural units. The upper crust is interpreted as the metasedimentary rocks of the Central Maine synclinorium with velocities that range from 6.2 to 6.3 km/s. Regions of relative lower velocity (6.0-6.1 km/s) within the upper crust are interpreted as granitic intrusions. Low velocity regions, modeled at 2.7 km depth with velocities around 5.4 km/s, are interpreted as seismic evidence for folding and doubling within the upper crustal metasedimentary sequence. At 12-15 km depth, the base of the synclinorium appears alternately as a strong reflector, indicating the presence of layering, and also as a weak reflector, especially NE of the Sebago pluton. A 4 km thick boundary layer at 24 km depth is interpreted as a major intracrustal shear zone in which the velocity increases from 6.4 to 6.8 km/s. The crust thickens from 36 to 40 km going from refraction experiment, the Quebec-Maine Transect Project. As part of this project, a 180-km-long seismic refraction profile was recorded along the axis of the Central Maine synclinorium. High near-surface velocities of 6.0-6.2 km/s made a conventional refraction analysis (including first arrivals) uninformative below about 10 km. Peak signal frequencies around 30 Hz, recorded at all offsets, and a trace spacing of 800 m led to severe spatial aliasing effects for secondary arrivals on the record sections. To allow a reliable deep structural interpretation, a coherency processing technique was applied to the data to enhance phase coherent secondary arrivals. In addition, interpretation of a coincident wide-angle reflection study provided constraints on the deep crustal velocities and structure. The crust beneath the Central Maine synclinorium can be described by three major structural units. The upper crust is interpreted as the metasedimentary rocks of the Central Maine synclinorium with velocities that range from 6.2 to 6.3 km/s. Regions of relative lower velocity (6.0-6.1 km/s) within the upper crust are interpreted as granitic intrusions. Low velocity regions, modeled at 2.7 km depth with velocities around 5.4 km/s, are interpreted as seismic evidence for folding and doubling within the upper crustal metasedimentary sequence. At 12-15 km depth, the base of the synclinorium appears alternately as a strong reflector, indicating the presence of layering, and also as a weak reflector, especially NE of the Sebago pluton. A 4 km thick boundary layer at 24 km depth is interpreted as a major intracrustal shear zone in which the velocity increases from 6.4 to 6.8 km/s. The crust thickens from 36 to 40 km going from the NE to the SW end of the profile. Surface rocks at the SW end of the profile have a metamorphic depth of burial of at least 15 km, indicating that the crust below the Central Maine synclinorium may have been thickened to at least 55 km during Paleozoic collisions. C1 US GEOL SURVEY,MENLO PK,CA 94025. PRINCETON UNIV,DEPT GEOL & GEOPHYS SCI,PRINCETON,NJ 08544. NR 36 TC 13 Z9 13 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12023 EP 12037 DI 10.1029/91JB00842 PG 15 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900027 ER PT J AU WALD, LA HEATON, TH AF WALD, LA HEATON, TH TI LG WAVES AND RG WAVES ON THE CALIFORNIA REGIONAL NETWORKS FROM THE DECEMBER 23, 1985 NAHANNI EARTHQUAKE SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID RAYLEIGH-TYPE LG; CRUSTAL STRUCTURE; MULTIMODE ANALYSIS; CENTRAL FRANCE; SIERRA-NEVADA; GREAT VALLEY; SAN-ANDREAS; PROPAGATION; ATTENUATION; MAGNITUDES AB We investigate Lg and Rg propagation in California using the central and southern California regional networks. Approximately 550 stations constitute these two short-period networks providing a dense converage of almost the entire state. The waveforms recorded from the December 23, 1985, Nahanni, Canada, earthquake are used to construct three profiles along the propagation path (almost N-S) and three perpendicular to the propagation path (almost E-W) to look at the nature of propagation of these two types of surface waves. Groups of records from stations in various geological and tectonic provinces in California are also examined in order to establish regional characteristics of the surface waves. We find that the propagation characteristics of Lg differ from those of Rg across California; Lg waves are apparently more sensitive to crustal heterogeneities. The most striking observations are the similarity of coda for both the Lg and the Rg waves within geologic provinces and the marked difference in coda between regions. These differneces are seen in the amplitudes, coda duration, shape of the energy envelope, frequency content, and sharpness of the phase initiation. In general, a decrease in the Moho depth near the Pacific Coast is correlated with a decrease in the surface wave amplitude, especially at higher frequencies (0.15-0.2 Hz). Most interesting is the association of the San Andreas fault with abrupt changes in the wave train amplitudes. The surface waves are amplified in the vicinity of the fault zone and then decrease in amplitude after the zone is crossed. In the Coast Ranges, amplitudes are low and waveform coherence is poor. The Rg phase dominates the record in the Sierra Nevada, and both surface waves are amplified by the thick sedimentary sequence of the Great Valley. RP WALD, LA (reprint author), US GEOL SURVEY,525 S WILSON AVE,PASADENA,CA 91106, USA. NR 43 TC 6 Z9 6 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12099 EP 12125 DI 10.1029/91JB00920 PG 27 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900031 ER PT J AU SIMPSON, RW HOWARD, KA HAXEL, GB AF SIMPSON, RW HOWARD, KA HAXEL, GB TI INTRODUCTION TO SPECIAL SECTION ON THE CALIFORNIA-ARIZONA CRUSTAL TRANSECT - CACTIS, .3. SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID PEACH SPRINGS TUFF; SOUTHEASTERN CALIFORNIA; COLORADO PLATEAU; BASIN; SYSTEM C1 US GEOL SURVEY,FLAGSTAFF,AZ 86001. RP SIMPSON, RW (reprint author), US GEOL SURVEY,MS 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12257 EP 12258 DI 10.1029/91JB01042 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900039 ER PT J AU MCCARTHY, J LARKIN, SP FUIS, GS SIMPSON, RW HOWARD, KA AF MCCARTHY, J LARKIN, SP FUIS, GS SIMPSON, RW HOWARD, KA TI ANATOMY OF A METAMORPHIC CORE COMPLEX - SEISMIC REFRACTION WIDE-ANGLE REFLECTION PROFILING IN SOUTHEASTERN CALIFORNIA AND WESTERN ARIZONA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID EASTERN MOJAVE DESERT; CRUST-MANTLE BOUNDARY; RANGE PROVINCE; NORMAL FAULTS; SYNTHETIC SEISMOGRAMS; DUCTILE DEFORMATION; SOUTHERN-CALIFORNIA; WHIPPLE MOUNTAINS; TRANSITION ZONE; IMPERIAL-VALLEY AB The metamorphic core complex belt in southeastern California and western Arizona is a NW-SE trending zone of unusually large Tertiary extension and uplift. Midcrustal rocks exposed in this belt raise questions about the crustal thickness, crustal structure, and the tectonic evolution of the region. Three seismic refraction/wide-angle reflection profiles, acquired and analyzed as a part of the U.S. Geological Survey's Pacific to Arizona Crustal Experiment, were collected to address these issues. The results presented here, which focus on the Whipple and Buckskin-Rawhide mountains, yield a consistent three-dimensional image of this part of the metamorphic core complex belt. The seismic refraction/wide-angle reflection data are of excellent quality and are characterized by six principal phases that can be observed on all three profiles. These phases include refractions from the near-surface and crystalline basement, reflections from boundaries in the middle and lower crust, and reflections and refractions from the upper mantle. The final model consists of a thin veneer (< 2 km) of upper plate and fractured lower plate rocks (1.5-5.5 km s-1) overlying a fairly homogeneous basement (approximately 6.0 km s-1) and a localized high-velocity (6.4 km s-1) body situated beneath the western Whipple Mountains. A prominent midcrustal reflection is identified beneath the Whipple and Buckskin-Rawhide mountains between 10 and 20 km depth. This reflector has an arch-like shape and is centered beneath, or just west of, the metamorphic core complex belt. This event is underlain by a weaker, approximately subhorizontal reflection at 24 km depth. Together, these two discontinuities define a lens-shaped midcrustal layer with a velocity of 6.35-6.5 km s-1. The apex of this midcrustal layer corresponds roughly to a region of major tectonic denudation and uplift (approximately 10 km) defined by surface geologic mapping and petrologic barometry studies. The layer thins to the northeast and is absent in the Transition Zone. The 6.35-6.5 km s-1 velocities are compatible with a diorite composition or a mixture of mafic and silicic rocks. This midcrustal layer is underlain by a higher-velocity lower crustal layer that is modeled as only 3-6 km thick beneath the metamorphic core complex belt and regions to the southwest. To the northest, however, this layer thickens to 8-10 km as the midcrustal layer pinches out above it. The velocity of the lower crust is constrained by traveltime modeling and is 6.6 +/- 0.15 km s-1 beneath the western Transition Zone and the metamorphic core complex belt; higher velocities may be present farther to the southwest where the layer is thin. The velocity of the lower crust is too low to accommodate significant amount of mafic underplating at the base of the crust. Instead, we interpret the velocities to indicate that the lower crust is passively thinned beneath these regions without significant addition of mafic mantle-derived intrusions. The crust-mantle boundary does not dome up beneath the core complexes but remains approximately subhorizontal at a depth of 26-28 km or, in the case of the Whipple Mountains, actually deepens; a 3-km crustal root is modeled. This lack of upward doming of the Moho, together with the vertical alignment of the metamorphic core complex belt over what are believed to be extension-related structures in the middle and lower crust, suggest that there is no lateral offset of upper crustal deformation from deeper zones of extension, as one would expect if extension occurred along crust-penetrating shear zones (Wemicke, 1981; Wemicke et al., 1985). Instead, domed and inflated middle crust and thinned lower crust directly underlie the region of greatest thinning of the upper crust. RP MCCARTHY, J (reprint author), US GEOL SURVEY,MS 999,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 80 TC 63 Z9 63 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12259 EP 12291 DI 10.1029/91JB01004 PG 33 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900040 ER PT J AU WILSON, JM MCCARTHY, J JOHNSON, RA HOWARD, KA AF WILSON, JM MCCARTHY, J JOHNSON, RA HOWARD, KA TI AN AXIAL VIEW OF A METAMORPHIC CORE COMPLEX - CRUSTAL STRUCTURE OF THE WHIPPLE AND CHEMEHUEVI MOUNTAINS, SOUTHEASTERN CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID HIGHLY EXTENDED TERRANES; SEISMIC-REFLECTION DATA; WEST-CENTRAL ARIZONA; ANGLE NORMAL FAULTS; CONTINENTAL EXTENSION; DETACHMENT FAULT; IMPERIAL-VALLEY; ORIGIN; NEVADA; BASIN AB A 135-km-long, NW-SE trending, seismic refraction/wide-angle reflection profile provides a unique along-strike view of the crustal structure of a belt of metamorphic core complexes in southeastern California: the Whipple, Chemehuevi, and Sacramento mountains metamorphic core complexes. Interpretation of the seismic data was done by two-dimensional forward modeling of travel times and amplitudes. The final model consists of (1) a thin (< 1.5 km) veneer of upper plate and fractured lower plate rocks (velocities of 1.5-5.3 km s-1) overlying a fairly homogeneous basement with velocities of 6.0 km s-1; (2) a localized, high-velocity (6.4 km s-1) body, situated directly beneath the Whipple Mountains; (3) a 6.3-6.4 km s-1 middle crust that is thickest beneath the core complexes; (4) a 6.65 +/- 0.15 km s-1 lower crust; (5) crustal thickness of 27 km with a deeper crustal root (3 km) beneath the Whipple Mountains metamorphic core complex; and (6) a P(n) velocity of 8.0 +/- 0.10 km s-1. The crustal structure that underlies the belt of metamorphic core complexes provides new insights into the processes that control extension in the deep crust. Upper crustal velocities are higher beneath the Whipple Mountains (where velocities increase to 6.4 km s-1 at approximately 5 km depth) than beneath the Chemehuevi and Sacramento mountains. In addition, midcrustal discontinuities rise 2-5 km beneath the Whipple complex compared to the other complexes. These observations support greater uplift and a slightly deeper midcrustal origin for the rocks now exposed in the core of the Whipple Mountains compared to rocks in the Chemehuevi and Sacramento mountains. Despite the enhanced uplift and extension in the Whipple Mountain, the crust is thicker here (30 km) than anywhere else along the Colorado River extensional corridor. This may be in part a relic of compressional and magmatic thickening during the Mesozoic. However, we suggest that inflation of the crust during Tertiary extension was the dominant mechanism. Both mantle-derived magmatism and lateral ductile inflow in the crust are proposed. C1 US GEOL SURVEY,MENLO PK,CA 94025. UNIV ARIZONA,DEPT GEOSCI,TUCSON,AZ 85721. NR 68 TC 10 Z9 10 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12293 EP 12311 DI 10.1029/91JB01003 PG 19 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900041 ER PT J AU KLEIN, DP AF KLEIN, DP TI CRUSTAL RESISTIVITY STRUCTURE FROM MAGNETOTELLURIC SOUNDINGS IN THE COLORADO PLATEAU-BASIN AND RANGE PROVINCES, CENTRAL AND WESTERN ARIZONA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID REMOTE-REFERENCE MAGNETOTELLURICS; ELECTRICAL-CONDUCTIVITY; SOUTHEASTERN CALIFORNIA; SEISMIC REFRACTION; CONTINENTAL-CRUST; MOJAVE-DESERT; UNITED-STATES; CASCADE RANGE; MANTLE; MOUNTAINS AB Resistivity structure to about 25 km depth is defined from two-dimensional modeling of 29 magnetotelluric (MT) soundings (0.002-5 Hz) that traverse 280 km of the southwestern Colorado Plateau, transition zone, and Basin and Range provinces in Arizona. From the surface to 5 km depth, the MT model suggests structural relationships between low-resistivity sedimentary and volcanic rocks (50-300 ohm m) and high-resistivity granitic and gneissic basement (500-9000 ohm m). In the Basin and Range province, the MT model and a seismic reflection section show a generally consistent distribution of supracrustal rocks that have relatively low to moderate resistivity (MT) and relatively strong, locally coherent reflectivity. The supracrustal zone defined by these physical properties is inferred to be composed of upper plate rocks above a middle Tertiary detachment fault system which has been mapped in surrounding ranges. Some low-angle fault zones inferred from seismic reflections to extend into high resistivity basement below the supracrustal rocks are not resolved by the MT model. A low-resistivity zone with a conductance of 500 S or more is modeled in the crust at an average depth of about 15 km in the Basin and Range province and transition zone and may deepen below the southwestern part of the Colorado Plateau. In the Basin and Range province, the top of the low resistivity may correspond to a reflective layer with a 6-s two-way-travel time. This deep low-resistivity zone might be caused by a small fraction of connected hydrous solutions or silicic melts. RP US GEOL SURVEY, DENVER FED CTR, MS 964, DENVER, CO 80225 USA. NR 87 TC 7 Z9 7 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12313 EP 12331 DI 10.1029/91JB00483 PG 19 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900042 ER PT J AU HENDRICKS, JD PLESCIA, JB AF HENDRICKS, JD PLESCIA, JB TI A REVIEW OF THE REGIONAL GEOPHYSICS OF THE ARIZONA TRANSITION ZONE SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID WESTERN UNITED-STATES; METAMORPHIC CORE COMPLEXES; COLORADO PLATEAU; SEISMIC REFRACTION; CRUSTAL STRUCTURE; SOUTHEASTERN CALIFORNIA; NORTH-AMERICA; GREAT BASIN; HEAT-FLOW; RANGE AB A review of existing geophysical information and new data presented in this special section indicate that major changes in crustal properties between the Basin and Range and Colorado Plateau occur in, or directly adjacent to, the region defined as the Arizona Transition Zone. Although this region was designated on a physiographic basis, studies indicate that it is also the geophysical transition between adjoining provinces. The Transition Zone displays anomalous crustal and upper mantle seismic properties, shallow Curie isotherms, high heat flow, and steep down-to-the-plateau Bouguer gravity gradients. Seismic and gravity studies suggest that the change in crustal thickness, from thin crust in the Basin and Range to thick crust in the Colorado Plateau, may occur as a series of steps rather than a planar surface. Anomalous P wave velocities, high heat flow, shallow Curie isotherms, and results of gravity modeling suggest that the upper mantle is heterogeneous in this region. A relatively shallow asthenosphere beneath the Basin and Range and Transition Zone contrasted with a thick lithosphere beneath the Colorado Plateau would be one explanation that would satisfy these geophysical observations. C1 CALTECH,JET PROP LAB,DIV EARTH & SPACE SCI,PASADENA,CA 91109. RP HENDRICKS, JD (reprint author), US GEOL SURVEY,2255 N GEMINI DR,FLAGSTAFF,AZ 86001, USA. RI Plescia, Jeffrey/B-7738-2016 NR 112 TC 16 Z9 16 U1 1 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12351 EP 12373 DI 10.1029/90JB01781 PG 23 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900044 ER PT J AU BRYANT, B NAESER, CW FRYXELL, JE AF BRYANT, B NAESER, CW FRYXELL, JE TI IMPLICATIONS OF LOW-TEMPERATURE COOLING HISTORY ON A TRANSECT ACROSS THE COLORADO PLATEAU-BASIN AND RANGE BOUNDARY, WEST CENTRAL ARIZONA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID DETACHMENT FAULT; THERMAL HISTORY; AGE; MINERALIZATION; MOUNTAINS; HORNBLENDE; DENUDATION; DIFFUSION; COMPLEX; ENGLAND AB Fission track ages of apatite and zircon from metamorphic, plutonic, and sedimentary rocks along a 80-km transect across the Colorado Plateau-Basin and Range boundary in west central Arizona show differences in the low-temperature cooling histories between the provinces. The transect extends from Cypress Mountain in the Colorado Plateau transition zone to the eastern Buckskin Mountains in the Basin and Range. Along the northeast margin of the Basin and Range province, metamorphic rocks exposed in the footwall of a major detachment fault system yield zircon and apatite fission track ages of 16-10 Ma. These ages are similar to K-Ar fusion ages of biotite and age minima of K-feldspar on Ar-40/Ar-39 age spectra and collectively indicate rapid cooling. One K-feldspar age spectrum has an age maximum of about 22.8 Ma, an age minimum of 11.8 Ma, and a spectrum whose shape is suggestive of reheating, possibly in middle Miocene time. The heating event was probably related to hydrothermal activity during emplacement of Cu and Mn deposits in and above the detachment fault zone. Effects of this heating are only locally detected in rocks above the detachment fault. In the Poachie Range fission track ages of apatite and zircon are 60-50 and 80-70 Ma, respectively. The disparity between the apatite and zircon ages indicates that the rocks cooled slowly in Late Cretaceous and early Tertiary time, probably due to gradual uplift and erosion. Total uplift and denudation in the area of the Poachie Range since Cretaceous time is 6 km or more. To the northeast of the range, fission track ages of apatite and zircon increase and diverge, indicating that apparent uplift decreased in that direction. The apatite ages from the Poachie Range are concordant with early Tertiary hornblende ages determined in other studies of lower plate rocks near the southwest end of the transect. The ages represent cooling of crystalline rocks after Cretaceous regional metamorphism and magmatism. Near Bagdad, 20 km northeast of the Poachie Range, 2 km or less of erosion has occurred since intrusion of high-level plutons and dikes and caldera formation in Late Cretaceous time. Remnants of an erosion surface that developed in middle Tertiary time are preserved in the transition zone. Volcanic and sedimentary rocks at least as old as early Miocene were deposited on the erosion surface and filled valleys cut into it. Dissection of these deposits began about 8 Ma. We interpret these data combined with those from other studies to indicate that in Cretaceous time southward thrusting and later extensive magmatism in the middle crust led to thickening and heating of the crust. The Cretaceous igneous rocks at Bagdad are high-level manifestations of this magmatism. Uplift and slow cooling occurred in Late Cretaceous and early Tertiary time. In late Oligocene and early Miocene time during northeast-southwest extension, middle crustal rocks moved southwest out from beneath the southwest margin of the transition zone. Tectonic denudation rapidly exposed the crust that had been brought up from a depth of 10 km or more and rapidly cooled in the eastern Buckskin and Harcuvar mountains. Middle Miocene reheating occurred locally in the lower plate, along the detachment, and in nearby parts of the upper plate. RP BRYANT, B (reprint author), US GEOL SURVEY,DENVER FED CTR,MS913,BOX 25046,DENVER,CO 80225, USA. NR 62 TC 16 Z9 16 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12375 EP 12388 DI 10.1029/90JB02027 PG 14 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900045 ER PT J AU ELSTON, DP YOUNG, RA AF ELSTON, DP YOUNG, RA TI CRETACEOUS-EOCENE (LARAMIDE) LANDSCAPE DEVELOPMENT AND OLIGOCENE-PLIOCENE DRAINAGE REORGANIZATION OF TRANSITION ZONE AND COLORADO PLATEAU, ARIZONA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID PEACH SPRINGS TUFF; CENOZOIC DRAINAGE; GEOCHRONOLOGY; EROSION; REGION AB Landscape development of central and northern Arizona can no longer be ascribed mainly to events of Miocene and Pliocene age. New information on the age and distribution of older Cenozoic deposits has led to the recognition of a regional Cretaceous-Paleocene(?) surface of erosion that conforms to major elements of the present topography and to the recognition that a formerly thick deposit of gravel accumulated on this regional surface of erosion. These relations cast new light on the history of evolution of the landscape and indicate a much greater age for the main landscape elements and a more complicated and prolonged history of erosion and deposition than has been previously supposed. The timing of events postulated for development of drainage on the Colorado Plateau can now be compared and partly reconciled with events recognized in the adjacent closely related Mountain Region (Transition Zone) of central Arizona. As a consequence of Late Cretaceous-Paleocene (Laramide) compression, central and northern Arizona underwent at least 1200 m of uplift, documented by paleochannels cut into erosionally truncated Paleozoic strata on the Hualapai Plateau of the southwestern Colorado Plateau. During this time, a highly irregular erosion surface was developed on Proterozoic rocks across the Transition Zone south of the Mogollon Rim, the scarp of the Mogollon Rim was eroded to its present height (600-900 m), and an extensive stripped surface was developed on resistant upper Paleozoic strata north of the rim. Deposition of several hundred meters of Paleocene-Eocene "Rim gravels" derived from highlands south and west of the region followed, covering much of the Cretaceous-Paleocene erosion surface. Nearly complete burial of the rim is suggested by the distribution of remnants of the Rim gravels across the erosional scarps and on high plateau areas north of the rim. A second increment of uplift, apparently occurring in late Eocene time and apparently recorded by a series of fission track cooling ages from the Marble and Grand canyons, is inferred to have been responsible for ending deposition of the Rim gravels, for initiating differential uplift of contemporaneous deposits (Canaan Peak and Claron formations) to their positions in the high plateaus of central Utah, and for causing the drainage reorganization required to explain the extensive removal of Rim gravels from much of the region. A southerly flowing ancestral Verde River related to the drainage reorganization removed much of the older gravel cover from the Transition Zone of central Arizona, resulting in a younger regional erosion surface having 600-900 m of relief, a surface closely approximating the Cretaceous-Paleocene erosion surface. Late Oligocene and early Miocene rocks locally rest unconformably on remnants of Rim gravels in the Transition Zone, indicating that the second episode of regional erosion had been completed by late Oligocene time. North of the Mogollon Rim, a west flowing(?) ancestral Colorado River is inferred to have become established on the Rim gravels, draining the interior parts of the Colorado Plateau and transporting detritus off the plateau. Exhumation of the Mogollon Rim and development of 600-900 m of topographic relief in the Transition Zone by an ancestral Verde River system suggests the potential for a comparable, coeval entrenchment of an ancestral Colorado River in Paleozoic strata north of the Mogollon Rim. Regional extension and volcanic activity ensued in late Oligocene to Pliocene time. The Oligocene erosion surface in the extensional basins of central Arizona became largely concealed by Miocene and Pliocene deposits as the Neogene climate became drier. In late Miocene and Pliocene time, perennial streams appear to have been lacking, transport of detritus appears to have been principally by flash flooding, little or no detritus appears to have been removed from the region, and much of the precipitation presumably moved by groundwater flow through the deposits of aggradation. A coeval episode of aggradation in the Grand Canyon is suggested by deposits that appear to have once choked much of the canyon. If this event parallels the episode of late Miocene and Pliocene aggradation recorded east, south, and west of the Grand Canyon, the Colorado River could have been incised to its present level by late Miocene time. A return to wetter conditions in late Pliocene time presumably was responsible for renewed erosion and reexcavation of older drainages and basins. An understanding of this Tertiary structural, erosional, and depositional history can be important for the geological analysis of geophysical transects across the region. C1 SUNY GENESEO,DEPT GEOL SCI,GENESEO,NY 14454. RP ELSTON, DP (reprint author), US GEOL SURVEY,2255 GEMINI DR,FLAGSTAFF,AZ 86001, USA. NR 87 TC 44 Z9 44 U1 0 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12389 EP 12406 DI 10.1029/90JB01978 PG 18 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900046 ER PT J AU SHERROD, DR TOSDAL, RM AF SHERROD, DR TOSDAL, RM TI GEOLOGIC SETTING AND TERTIARY STRUCTURAL EVOLUTION OF SOUTHWESTERN ARIZONA AND SOUTHEASTERN CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID K-AR AGES; SOUTHERN-CALIFORNIA; ROCKS; MOUNTAINS; STRATIGRAPHY; TECTONICS; NEVADA AB Volcanic and sedimentary rocks and structures record the Tertiary structural evolution of the lower Colorado River region in southwestern Arizona and southeastern California. A late Eocene or early Oligocene (prior to approximately 33 Ma) episode of faulting is indicated by medium- to coarse-grained arkosic rocks in the Chocolate and southern Trigo Mountains. Much of the area was relatively quiescent tectonically during extrusion of volcanic rocks from approximately 33 to 22 Ma, but the southernmost part was periodically uplifted and eroded into its underlying crystalline rocks. A major episode of extensional deformation and tilting occurred after deposition of welded tuff about 22 Ma and affected the entire area from the Palo Verde Mountains on the west to the Kofa Mountains on the east. Extension-related faulting quickly waned and had largely ceased by about 20 Ma in the Kofa Mountains; elsewhere the timing is poorly constrained. By approximately 13 Ma, thick alluvial fans filled many grabens and half grabens among tilted fault blocks throughout the area. Volcanism in the lower Colorado River region may have been coincident with a broad structural depression now oriented east-west. The northern limit of the volcanic terrane defines a tilt-domain boundary. The northern boundary, reaching from the New Water Mountains in Arizona to the little Chuckwalla Mountains in California, ultimately evolved to separate a terrane of relatively untilted crystalline horsts on the north from a series of east or northeast dipping fault blocks on the south. The southern margin is less well defined but is subparallel to the northern boundary and to the Chocolate Mountains anticlinorium. C1 US GEOL SURVEY,WESTERN MINERAL RESOURCE BRANCH,MENLO PK,CA 94025. NR 60 TC 19 Z9 19 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12407 EP 12423 DI 10.1029/90JB02688 PG 17 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900047 ER PT J AU HILLHOUSE, JW WELLS, RE AF HILLHOUSE, JW WELLS, RE TI MAGNETIC FABRIC, FLOW DIRECTIONS, AND SOURCE AREA OF THE LOWER MIOCENE PEACH SPRINGS TUFF IN ARIZONA, CALIFORNIA, AND NEVADA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID CENTRAL MOJAVE DESERT; SAN-JUAN MOUNTAINS; SOUTHEASTERN CALIFORNIA; PALEOMAGNETIC EVIDENCE; COLORADO-PLATEAU; ORIENTATION DATA; SOUTHERN NEVADA; ANISOTROPY; SUSCEPTIBILITY; REMANENCE AB We have used anisotropy of magnetic susceptibility (AMS) to define the flow fabric and possible source area of the Peach Springs Tuff, a widespread rhyolitic ash flow tuff in the Majave Desert and Great Basin of California, Arizona, and Nevada. The tuff is an important stratigraphic marker from the Colorado Plateau to Barstow, California, a distance of 350 km; however, the location of its source caldera is unknown. Dated at 18.5 Ma by Ar-40/Ar-39, the tuff erupted during the early stages of Miocene extension along the lower Colorado River. The thicker accumulations (> 100 m) occur at Kingman, Arizona, and in the Piute Mountains, California, on opposite sides of the Colorado River extensional corridor. Our AMS studies produced well-defined magnetic lineations in 30 of 42 sites distributed throughout the tuff. Typical ratios of the principal AMS axes are 1.01 for the magnetic lineation (k(max)/k(int) and 1.02 for the foliation (k(int)/k(min); the bulk magnetic susceptibility of the Peach Springs Tuff averages 2.0 x 10(-3) in the SI unit system. The subhorizontal lineations, which presumably parallel the flow directions, form a pattern radiating outward from the approximate center of the outcrop area. Magnetic foliations define an imbication that generally dips away from the distal margins and toward the center of the outcrop of the tuff. The lineation and imbrication indicate a source region near the southern tip of Nevada. Defining the best intersection of the AMS lineations required restoration of major extension, strike-slip faulting, and associated tectonic rotation in the disrupted tuff. The optimum intersection of magnetic lineations lies in the southern Black Mountains of Arizona on the eastern side of the Colorado River extensional corridor. No caldera structures are known from that area, but the area contains thick sections of the Peach Springs Tuff above a silicic volcanic center. The caldera may be buried under younger deposits in the Mohave Valley of Arizona. Tertiary granite in the Newberry Mountains may represent a deeper level of the Peach Springs Tuff vent that has been exhumed by detachment faulting. RP HILLHOUSE, JW (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 975,MENLO PK,CA 94025, USA. NR 65 TC 69 Z9 70 U1 2 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12443 EP 12460 DI 10.1029/90JB02257 PG 18 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900049 ER PT J AU HOWARD, KA AF HOWARD, KA TI INTRUSION OF HORIZONTAL DIKES - TECTONIC SIGNIFICANCE OF MIDDLE PROTEROZOIC DIABASE SHEETS WIDESPREAD IN THE UPPER CRUST OF THE SOUTHWESTERN UNITED-STATES SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID EASTERN MOJAVE DESERT; SEISMIC-REFLECTION; TRANSITION ZONE; GRAND-CANYON; LAKE NIPIGON; RIFT SYSTEM; CALIFORNIA; ARIZONA; STRESS; REGION AB Initially horizontal sheet intrusions of Middle Proterozoic diabase are abundant in a region 650 by 300 km across in Arizona and California. The diabase forms discordant sheets in basement granite and gneiss and sills in overlying shelf sedimentary sequences. Massive granite is the most common basement host for the sheets, probably because it fractured more easily than foliated hosts during sheet emplacement. Steep feeder dikes are rare compared to the sheets. The diabase in many places is exposed in fault blocks that were tilted during Tertiary tectonic extension. Structure sections restored from the map patterns of upended blocks show that the sheets were intruded at levels throughout the upper crust, to depths of at least 13 km. Sheet intrusion implies a vertical orientation of the least compressive stress, so I conclude that the crust was under tectonic compression or in an isotropic state of stress at the time of diabase intrusion about 1.1 Ga. Magma overpressures, water encountered by rising magma, vertical changes in the crustal stress regime, and flotation of low-density granite all may be important factors for sheet intrusion. The stress conditions suggested by the presence of the sheets argue against an extensional tectonic regime earlier proposed for the diabase event. The diabase province contrasts structurally with similar-age provinces of basaltic magmatism elsewhere in North America that show evidence of tectonic extension, such as the midcontinent rift. The consistent orientations of the sheets commonly allow them to be used as structural markers for postdiabase deformation of basement blocks. Sheet intrusions in the geologic record may be seriously underreported. Their recognition is important for the interpretation of seismic reflection profiles of continental crust. Sheets in Arizona may be responsible for the Bagdad reflection sequence, which extends to depths of at least 15 km. RP HOWARD, KA (reprint author), US GEOL SURVEY,WESTERN REG GEOL,345 MIDDLEFIELD RD,MS 975,MENLO PK,CA 94025, USA. NR 141 TC 50 Z9 50 U1 1 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12461 EP 12478 DI 10.1029/91JB00112 PG 18 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900050 ER PT J AU WARD, PL AF WARD, PL TI ON PLATE-TECTONICS AND THE GEOLOGIC EVOLUTION OF SOUTHWESTERN NORTH-AMERICA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID METAMORPHIC CORE COMPLEXES; PORPHYRY COPPER-DEPOSITS; MENDOCINO FRACTURE-ZONE; WEST-CENTRAL ARIZONA; SOUTHERN-CALIFORNIA; BAJA-CALIFORNIA; SIERRA-NEVADA; UNITED-STATES; PACIFIC-PLATE; CORDILLERAN TECTONICS AB Very rapid subduction of the Farallon plate under southwestern North America between 60 and 40 Ma was accompanied by a relatively low volume of magmatism throughout the southwestern United States and northern Mexico. Between 40 and 20 Ma, when subduction slowed significantly and in one area may have even stopped, magmatism became widespread and voluminous from Nevada and Utah to central Mexico. This correlation of rapid subduction with a relatively low volume of magmatism can be explained by the observation that subduction-related andesitic arc volcanism, often formed in a Laramide-style compressional regime, is relatively low volume compared to continental volcanism. The shallow roots of arc volcanic systems are clearly exposed in the porphyry copper deposits found in currently active arcs and common throughout southwestern North America between 60 and 50 Ma. By 43 Ma, worldwide plate motions changed, the Pacific plate began moving away from North America, and subduction of the Farallon plate slowed. By around 36 Ma, the easternmost part of the East Pacific Rise, which was located between the Pioneer and Murray fracture zones, approached the trench and the young, hot, buoyant lithosphere appears to have clogged part of the subduction zone. Uplift on land became widespread. Voluminous continental magmatism formed the Sierra Madre Occidental (SMO) of Mexico, one of the largest batholiths in the world, as well as volcanic centers now exposed in the San Juan Mountains of Colorado and the Rio Grande Rift of New Mexico. Vectors of motion of the Pacific plate relative to the North American plate determined by Stock and Molnar (1988) are consistent with formation of a transtensional environment along the plate boundary sufficient to create a 100- to 200-km-wide void just landward of the old volcanic arc. While the SMO batholith was forming within this void, the Monterey and Arguello microplates just offshore to the west were broken off from the Farallon plate and rotated so that the East Pacific Rise in this immediate area became nearly perpendicular to the trench and perpendicular to the vector of motion of the Pacific plate relative to North America. Formation of the SMO batholith was followed between 24 and 20 Ma by a major increase in the rate of subduction of the Guadalupe plate, a fragment of the former Farallon plate, and by increasing mylonitization, extension, and uplift in the metamorphic core complexes that extend northwestward through southern Arizona from the northern end of the SMO batholith. The plate margin underwent another major change between 12.5 and 10 Ma when subduction again stopped, strike slip faulting became dominant along the coast, the Basin and Range Province opened, and numerous tectonostratigraphic terrances in southern California underwent large rotations. By 3 Ma a large, new terrane had been served from North America immediately west of the SMO batholith as the Gulf of California opened. These observations can be explained by a model for the weakening and ultimate falling apart of the uppermost part of the subducted oceanic plate in the 20-30 m.y. after the end of rapid subduction. As the plate falls apart, not only is compressional stress relieved, but significant backslip along the old subduction zone is also possible, perhaps bringing blueschists rapidly upward from 20- to 30-km depths. RP WARD, PL (reprint author), US GEOL SURVEY,MS 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 144 TC 33 Z9 33 U1 2 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUL 10 PY 1991 VL 96 IS B7 BP 12479 EP 12496 DI 10.1029/91JB00606 PG 18 WC Geosciences, Multidisciplinary SC Geology GA FW819 UT WOS:A1991FW81900051 ER PT J AU LITWIN, RJ TRAVERSE, A ASH, SR AF LITWIN, RJ TRAVERSE, A ASH, SR TI PRELIMINARY PALYNOLOGICAL ZONATION OF THE CHINLE FORMATION, SOUTHWESTERN USA, AND ITS CORRELATION TO THE NEWARK SUPERGROUP (EASTERN USA) SO REVIEW OF PALAEOBOTANY AND PALYNOLOGY LA English DT Article ID LATE TRIASSIC PALYNOLOGY; DOLORES FORMATIONS; LUNGFISH BURROWS; COLORADO PLATEAU; PALYNOSTRATIGRAPHY; DOLOMITES; SEDIMENTS; ARIZONA; ORIGIN; SPORES AB Three informal palynological assemblage zones can be distinguished in samples from Chinle Formation outcrops in Utah, Arizona and New Mexico. The oldest zone (zone I) is in the Temple Mountain Member in southeastern Utah; the middle zone (zone II) is in the Shinarump, Moss Back, Monitor Butte and (lower part of the) Petrified Forest Members (Utah, Arizona and New Mexico); the youngest zone (zone III) is in the upper Petrified Forest Member and siltstone member in Arizona and Utah and the siltstone member in northcentral New Mexico. Present palynological evidence suggests that Chinle deposition on the Colorado Plateau began locally in late Carnian time and continued at least into the early part of Norian time of the Late Triassic period. Because the upper boundary of the Chinle Formation is an unconformity and the overlying formations are palynologically barren, the length of time represented by this stratigraphic hiatus is not known with certainty. Current palynological evidence suggests, however, that the unconformity at the top of the Chinle cannot be older than early Norian nor younger than Hettangian. Zones I, II and III can now be recognized in the palynomorph assemblage sequences from the Eastern Mesozoic basins, which modifies earlier palynological zonations for the lower portions of the Newark Supergroup. This is based on our identification of palynomorphs not previously known from portions of the Newark Supergroup and the discovery that specific biomarker taxa combinations are the same for both the western and eastern palynomorph sequences. At present palynomorph assemblages from the Chinle Formation and Newark Supergroup compare more closely for zones II and III than they do for zone I, but research is still in progress. C1 PENN STATE UNIV, UNIVERSITY PK, PA 16802 USA. WEBER STATE UNIV, DEPT GEOL, OGDEN, UT 84408 USA. RP LITWIN, RJ (reprint author), US GEOL SURVEY, 970 NATL CTR, RESTON, VA 22092 USA. NR 84 TC 66 Z9 70 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0034-6667 J9 REV PALAEOBOT PALYNO JI Rev. Palaeobot. Palynology PD JUL 10 PY 1991 VL 68 IS 3-4 BP 269 EP 287 DI 10.1016/0034-6667(91)90028-2 PG 19 WC Plant Sciences; Paleontology SC Plant Sciences; Paleontology GA FX189 UT WOS:A1991FX18900007 ER PT J AU GLOERSEN, P CAMPBELL, WJ AF GLOERSEN, P CAMPBELL, WJ TI RECENT VARIATIONS IN ARCTIC AND ANTARCTIC SEA-ICE COVERS SO NATURE LA English DT Article ID CARBON-DIOXIDE; TEMPERATURE; VARIABILITY AB Variations in the extents of sea-ice cover at the poles and the areas of open water enclosed within them were observed every other day during the interval 1978-1987 by a satellite-borne scanning multispectral microwave radiometer. A band-limited regression technique shows that the trends in coverage of the Arctic and Antarctic sea-ice packs are not the same. During these nine years, there are significant decreases in ice extent and open-water areas within the ice cover in the Arctic, whereas in the Antarctic, there are no significant trends. C1 UNIV PUGET SOUND,US GEOL SURVEY,ICE & CLIMATE PROJECT,TACOMA,WA 98416. RP GLOERSEN, P (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROSPHER PROC LAB,CODE 971,GREENBELT,MD 20771, USA. NR 23 TC 107 Z9 108 U1 2 U2 6 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD JUL 4 PY 1991 VL 352 IS 6330 BP 33 EP 36 DI 10.1038/352033a0 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FV178 UT WOS:A1991FV17800060 ER PT J AU WEAVER, LR PARDUE, GB NEVES, RJ AF WEAVER, LR PARDUE, GB NEVES, RJ TI REPRODUCTIVE-BIOLOGY AND FISH HOSTS OF THE TENNESSEE CLUBSHELL PLEUROBEMA-OVIFORME (MOLLUSCA, UNIONIDAE) IN VIRGINIA SO AMERICAN MIDLAND NATURALIST LA English DT Article ID GLOCHIDIA AB The reproductive cycle and fish hosts of the freshwater mussel Pleurobema oviforme were determined during a 14-mo study (1979-1980) in Big Moccasin Creek, southwestern Virginia. Histological sectioning of mussel gonads collected throughout the year showed that gametogenesis for both sexes began in late spring and continued into early autumn; fertilization began in late March. Glochidial development in the outer gills of females required 3-5 wk. Judged by biweekly samples of stream drift, glochidia were released from mid-April through july. Six species of cyprinids, collected between May and September 1979, were naturally infested with amblemine glochidia. Induced infestations of putative fish hosts in the laboratory confirmed five host species: whitetail shiner (Notropis galacturus), common shiner (N. cornutus), river chub (Nocomis micropogon), stoneroller (Campostoma anomalum) and fantail darter (Etheostoma flabellare). C1 VIRGINIA POLYTECH INST & STATE UNIV, US FISH & WILDLIFE SERV, DEPT FISHERIES & WILDLIFE SCI, BLACKSBURG, VA 24061 USA. NR 21 TC 27 Z9 28 U1 2 U2 6 PU AMER MIDLAND NATURALIST PI NOTRE DAME PA UNIV NOTRE DAME, BOX 369, ROOM 295 GLSC, NOTRE DAME, IN 46556 USA SN 0003-0031 EI 1938-4238 J9 AM MIDL NAT JI Am. Midl. Nat. PD JUL PY 1991 VL 126 IS 1 BP 82 EP 89 DI 10.2307/2426152 PG 8 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA GA853 UT WOS:A1991GA85300008 ER PT J AU SMITH, RL HOWES, BL GARABEDIAN, SP AF SMITH, RL HOWES, BL GARABEDIAN, SP TI INSITU MEASUREMENT OF METHANE OXIDATION IN GROUNDWATER BY USING NATURAL-GRADIENT TRACER TESTS SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID LAKE WASHINGTON; GRAVEL AQUIFER; TRANSPORT; SEDIMENTS; RATES; SAND; BIOTRANSFORMATION; DISTRIBUTIONS; BACTERIA; SOIL AB Methane oxidation was measured in an unconfined sand and gravel aquifer (Cape Cod, Mass.) by using in situ natural-gradient tracer tests at both a pristine, oxygenated site and an anoxic, sewage-contaminated site. The tracer sites were equipped with multilevel sampling devices to create target grids of sampling points; the injectate was prepared with groundwater from the tracer site to maintain the same geochemical conditions. Methane oxidation was calculated from breakthrough curves of methane relative to halide and inert gas (hexafluoroethane) tracers and was confirmed by the appearance of C-13-enriched carbon dioxide in experiments in which C-13-enriched methane was used as the tracer. A V(max) for methane oxidation could be calculated when the methane concentration was sufficiently high to result in zero-order kinetics throughout the entire transport interval. Methane breakthrough curves could be simulated by modifying a one-dimensional advection-dispersion transport model to include a Michaelis-Menten-based consumption term for methane oxidation. The K(m) values for methane oxidation that gave the best match for the breakthrough curve peaks were 6.0 and 9.0-mu-M for the uncontaminated and contaminated sites, respectively. Natural-gradient tracer tests are a promising approach for assessing microbial processes and for testing in situ bioremediation potential in groundwater systems. C1 WOODS HOLE OCEANOG INST,DEPT BIOL,WOODS HOLE,MA 02543. US GEOL SURVEY,DIV WATER RESOURCES,MARLBOROUGH,MA 01752. RP SMITH, RL (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,LAKEWOOD,CO 80225, USA. RI Smith, Richard/A-6733-2008 OI Smith, Richard/0000-0002-3829-0125 NR 35 TC 57 Z9 60 U1 2 U2 22 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD JUL PY 1991 VL 57 IS 7 BP 1997 EP 2004 PG 8 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA FV547 UT WOS:A1991FV54700019 PM 1892389 ER PT J AU CLEVELAND, L LITTLE, EE INGERSOLL, CG WIEDMEYER, RH HUNN, JB AF CLEVELAND, L LITTLE, EE INGERSOLL, CG WIEDMEYER, RH HUNN, JB TI SENSITIVITY OF BROOK TROUT TO LOW PH, LOW CALCIUM AND ELEVATED ALUMINUM CONCENTRATIONS DURING LABORATORY PULSE EXPOSURES SO AQUATIC TOXICOLOGY LA English DT Article DE BROOK TROUT; PH; ALUMINUM; PULSE EXPOSURE; SURVIVAL; GROWTH; WHOLE-BODY IONS ID SALMON SALMO-SALAR; SALVELINUS-FONTINALIS FRY; LOW ENVIRONMENTAL PH; WHOLE-BODY IONS; RAINBOW-TROUT; WATER ACIDITY; SWIM-UP; TOXICITY; RESPONSES; ALEVINS AB Yolk-sac larvae of brook trout (Salvelinus fontinalis) were exposed to four sequential low pH and calcium (Ca) pulses, nominally ranging from pH 6.5 to 4.0 in 0.5 pH unit increments, with and without 300-mu-g/l aluminium (Al) in 28-day toxicity tests. Calcium concentrations during the pulses varied from 0.5 to 1.3 mg/l. Swim-up larvae that had begun to feed were exposed to a single pulse of the same pH and Ca concentrations with 300-mu-g/l Al. The larvae were allowed to recover for 120-h at circumneutral pH and Ca concentration that varied from 2.1 to 3.3 mg/l after each pulse exposure. Effects of the pulse exposures on survival, growth, whole-body ion concentrations, and behavioral development were monitored. Mortality of larvae was significant in all low pH and Ca treatments with Al after the first pulse and after the first low pH and Ca pulse at pH 4.0. Growth was significantly reduced among larvae exposed to the low pH and Ca pulses at pH 4.0. In general, growth was most severely affected among larvae exposed to the low pH and Ca pulses with Al at pH 6.1 and lower. Relative to controls, the low pH and Ca pulse exposures with and without Al reduced whole-body Na+, Ca2+, K+, Mg2+, P, and Cl-. Whole-body Ca2+ was most severely reduced followed by Na+, K+, Cl-, P, and Mg2+. The pulse exposures also caused delayed development and significant reductions in swimming activity and feeding of the larvae. These results support field observations that cyclic pH and Ca depressions, and concurrent increases in Al concentrations may cause mortality and have other adverse effects on natural fish populations. RP CLEVELAND, L (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,ROUTE 2,4200 NEW HAVEN RD,COLUMBIA,MO, USA. NR 43 TC 24 Z9 24 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-445X J9 AQUAT TOXICOL JI Aquat. Toxicol. PD JUL PY 1991 VL 19 IS 4 BP 303 EP 318 DI 10.1016/0166-445X(91)90055-E PG 16 WC Marine & Freshwater Biology; Toxicology SC Marine & Freshwater Biology; Toxicology GA FY178 UT WOS:A1991FY17800004 ER PT J AU FABACHER, DL BESSER, JM SCHMITT, CJ HARSHBARGER, JC PETERMAN, PH LEBO, JA AF FABACHER, DL BESSER, JM SCHMITT, CJ HARSHBARGER, JC PETERMAN, PH LEBO, JA TI CONTAMINATED SEDIMENTS FROM TRIBUTARIES OF THE GREAT-LAKES - CHEMICAL CHARACTERIZATION AND CARCINOGENIC EFFECTS IN MEDAKA (ORYZIAS-LATIPES) SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; INVITRO GENETIC TOXICITY; METHYLAZOXYMETHANOL-ACETATE; RAINBOW-TROUT; ENVIRONMENTAL CARCINOGENESIS; HEPATIC-TUMORS; CRUDE-OIL; FISH; INDUCTION; NEOPLASMS AB Sediments from four inshore industrial sites and a reference site in the Great Lakes were extracted with organic solvents to produce a crude extract, which was separated on alumina into two fractions: predominantly polycyclic aromatic hydrocarbons; and predominantly nitrogen-containing polycyclic aromatic compounds. Crude extracts were redissolved in acetone and analyzed by gas chromatography and gas chromatography-mass spectrometry. The acetone-redissolved crude extracts from the four industrialized sites contained 5.6-313.3-mu-g total polycyclic aromatic compounds/g sediment and 3.0-36.4-mu-g other compounds/g sediment. In addition to the typical EPA priority pollutants, a substantial amount (228.7-mu-g/g sediment) of alkyl-polycyclic-aromatic compounds was detected in sediments from one of the industrialized sites. Extracts from the reference site contained 1.55-mu-g total polycyclic aromatic compounds/g sediment. Medaka (Oryzias latipes) were exposed to multiple pulse doses of acetone-redissolved extracts and fractions. Medaka were also exposed to a known carcinogen, methylazoxymethanol acetate, to verify that chemicals produced tumors in the test fish. Acetone-redissolved extracts and fractions from contaminated sediments were toxic to medaka. Fin erosion and non-neoplastic liver abnormalities were more prevalent in medaka after exposure to acetone-redissolved extracts and fractions from contaminated sediments. Neoplasms previously associated with chemical exposure in wild fishes were induced in medaka exposed to acetone-redissolved extracts and fractions from two of the contaminated sites, but not from the reference site or controls. These findings further support the hypothesis that chemical contaminants in sediments are involved in epizootics of neoplasms in wild fishes at contaminated sites. C1 NATL MUSEUM NAT HIST,REGISTRY TUMORS LOWER ANIM,WASHINGTON,DC 20560. RP FABACHER, DL (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,ROUTE 2,4200 NEW HAVEN RD,COLUMBIA,MO 65201, USA. NR 63 TC 23 Z9 24 U1 2 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD JUL PY 1991 VL 21 IS 1 BP 17 EP 34 PG 18 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FR206 UT WOS:A1991FR20600003 PM 1898114 ER PT J AU TILLITT, DE ANKLEY, GT VERBRUGGE, DA GIESY, JP LUDWIG, JP KUBIAK, TJ AF TILLITT, DE ANKLEY, GT VERBRUGGE, DA GIESY, JP LUDWIG, JP KUBIAK, TJ TI H4IIE RAT HEPATOMA-CELL BIOASSAY-DERIVED 2,3,7,8-TETRACHLORODIBENZO-PARA-DIOXIN EQUIVALENTS IN COLONIAL FISH-EATING WATERBIRD EGGS FROM THE GREAT-LAKES SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID ARYL-HYDROCARBON HYDROXYLASE; DIBENZO-PARA-DIOXINS; COPLANAR POLYCHLORINATED-BIPHENYLS; INVITRO AHH INDUCTION; O-DEETHYLASE; CHICK-EMBRYOS; HERRING-GULLS; AROMATIC-HYDROCARBONS; CLEFT-PALATE; FACTORS TEFS AB Fish-eating waterbirds from the Great Lakes of North America have shown symptoms of poisoning similar to those observed in laboratory exposures of various avian species to planar halogenated hydrocarbons (PHHs). PHHs, include among others, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) and have been implicated in some of the reproductive problems of Great Lakes waterbirds. The objectives of this study were to assess the overall potencies of PCB-containing extracts from colonial waterbird eggs taken from the Great Lakes and to compare the potencies with the location and spatial distribution of the colonies. The potencies of the extracts were assessed by their ability to induce cytochrome P450IA1-associated ethoxyresorufin O-deethylase (EROD) activity in H4IIE rat hepatoma cells as compared to the standard, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The H4IIE bioassay-derived TCDD-equivalents (TCCD-EQs) in the waterbird eggs concur with residue analyses and biological data from other studies. The greatest concentrations of TCDD-EQs were found in waterbird eggs from historically polluted, industrialized or urbanized areas in which the reproductive impairment of colonial waterbirds was most severe. However, significant concentrations of TCDD-EQs were detected at all sites tested; with a range of 49 to 415 pg TCDD-EQ/g egg, uncorrected for extraction efficiencies. The H4IIE bioassay proved to be a useful biomonitoring tool to assess the overall potency of complex PHH mixtures in environmental samples. C1 ECOL RES SERV,ANN ARBOR,MI 48104. US FISH & WILDLIFE SERV,ECOL SERV,FIELD OFF,E LANSING,MI 48823. MICHIGAN STATE UNIV,DEPT FISHERIES & WILDLIFE,PESTICIDE RES CTR,INST ENVIRONM TOXICOL,E LANSING,MI 48824. NR 57 TC 102 Z9 103 U1 2 U2 8 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD JUL PY 1991 VL 21 IS 1 BP 91 EP 101 PG 11 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FR206 UT WOS:A1991FR20600013 PM 1654867 ER PT J AU MENKENS, GE MALECKI, RA AF MENKENS, GE MALECKI, RA TI WINTER SIGHTINGS OF CANADA GEESE, BRANTA-CANADENSIS, BANDED IN NORTHERN QUEBEC AND JAMES BAY SO CANADIAN FIELD-NATURALIST LA English DT Article DE CANADA GEESE; BRANTA-CANADENSIS; ATLANTIC FLYWAY; BREEDING POPULATIONS; NECKBANDS; WINTER DISTRIBUTION AB January observations of Canada Geese (Branta canadensis) neckbanded in three northern Canada breeding areas were used to examine the relationship between goose breeding and wintering distributions and to determine if winter observations could be used to delineate breeding goose populations. Winter distributions of birds from three breeding areas differed and these differences were consistent between 1987-1989. However, all breeding segments overlapped sufficiently in their use of winter areas to preclude their delineation using winter observations alone. C1 CORNELL UNIV,US FISH & WILDLIFE SERV,ITHACA,NY 14853. NR 0 TC 1 Z9 1 U1 2 U2 3 PU OTTAWA FIELD-NATURALISTS CLUB PI OTTAWA PA PO BOX 35069, WESTGATE PO, OTTAWA ON K1Z 1A2, CANADA SN 0008-3550 J9 CAN FIELD NAT JI Can. Field-Nat. PD JUL-SEP PY 1991 VL 105 IS 3 BP 350 EP 353 PG 4 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA HF035 UT WOS:A1991HF03500006 ER PT J AU WILCOX, DA MEEKER, JE AF WILCOX, DA MEEKER, JE TI DISTURBANCE EFFECTS ON AQUATIC VEGETATION IN REGULATED AND UNREGULATED LAKES IN NORTHERN MINNESOTA SO CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE LA English DT Article DE RESERVOIRS; LAKE-LEVEL REGULATION; WINTER DRAWDOWN; AQUATIC VEGETATION; GROWTH FORM; DISTURBANCE ID SHORELINE VEGETATION; MACROPHYTES; ZONATION AB The effects of water-level regulation on aquatic macrophyte communities were investigated by comparing two regulated lakes in northern Minnesota with a nearby unregulated lake. Natural annual fluctuations of about 1.8 m were replaced with fluctuations of 1.1 m and 2.7 m in the regulated lakes, and the timing of water-level changes was also altered. Quadrats were sampled along transects that followed depth contours representing different plant habitats in the unregulated lake. Ordinations showed that the macrophyte communities at all sampled depths of the regulated lakes differed from those in the unregulated lake. The unregulated lake supported structurally diverse plant communities at all depths. In the lake with reduced fluctuations, only four taxa were present along transects that were never dewatered; all were erect aquatics that extended through the entire water column. In the lake with increased fluctuations, rosette and mat-forming species dominated transects where drawdown occurred in early winter and disturbance resulted from ice formation in the sediments. The natural hydrologic regime at the unregulated lake resulted in intermediate disturbance and high diversity. There was either too little or too much disturbance from water-level fluctuations in the regulated lakes, both resulting in reduced structural diversity. C1 UNIV WISCONSIN,DEPT BOT,MADISON,WI 53706. RP WILCOX, DA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,1451 GREEN RD,ANN ARBOR,MI 48105, USA. NR 25 TC 69 Z9 77 U1 2 U2 15 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4026 J9 CAN J BOT JI Can. J. Bot.-Rev. Can. Bot. PD JUL PY 1991 VL 69 IS 7 BP 1542 EP 1551 PG 10 WC Plant Sciences SC Plant Sciences GA GE796 UT WOS:A1991GE79600020 ER PT J AU KINCHELOE, KL STEHN, RA AF KINCHELOE, KL STEHN, RA TI VEGETATION PATTERNS AND ENVIRONMENTAL GRADIENTS IN COASTAL MEADOWS ON THE YUKON-KUSKOKWIM DELTA, ALASKA SO CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE LA English DT Article DE ALASKA; ORDINATION; PLANT COMMUNITIES; SALT MARSH; TUNDRA; YUKON-KUSKOKWIM DELTA ID DETRENDED CORRESPONDENCE-ANALYSIS; SALT MARSHES; PLANT ZONATION; ISLAND; BAY; ELEVATION AB Tundra vegetation and environmental variables were sampled on the Yukon-Kuskokwim delta in western Alaska. On transects extending from intertidal mudflat to upland tundra, we estimated cover by vascular plant species, soil moisture, salinity, relative elevation, depth to permafrost, and distance upriver from the coast. Two-way indicator species analysis (TWINSPAN) classified 21 communities. Ordination by detrended correspondence analysis (DECORANA) revealed a gradient correlated with the combination of elevation, permafrost depth, and salinity along the first axis for both upriver and downriver transects. C1 US FISH & WILDLIFE SERV,ALASKA FISH & WILDLIFE RES CTR,1011 E TUDOR RD,ANCHORAGE,AK 99503. NR 39 TC 36 Z9 36 U1 3 U2 7 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4026 J9 CAN J BOT JI Can. J. Bot.-Rev. Can. Bot. PD JUL PY 1991 VL 69 IS 7 BP 1616 EP 1627 PG 12 WC Plant Sciences SC Plant Sciences GA GE796 UT WOS:A1991GE79600027 ER PT J AU HEWETT, SW KRAFT, CE JOHNSON, BL AF HEWETT, SW KRAFT, CE JOHNSON, BL TI CONSUMPTION, GROWTH, AND ALLOMETRY - A COMMENT SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Letter ID AMONG-POPULATION VARIABILITY; STIZOSTEDION-VITREUM-VITREUM; FOOD-CONSUMPTION; YELLOW PERCH; FISH GROWTH; LAKE-MICHIGAN; BODY-WEIGHT; DAILY RATES; MEAL SIZE; MODELS C1 US FISH & WILDLIFE SERV, NATL FISHERIES RES CTR, LA CROSSE, WI 54602 USA. UNIV WISCONSIN, SEA GRANT OFF, GREEN BAY, WI 54311 USA. RP UNIV MARYLAND, CHESAPEAKE BIOL LAB, CTR ESTUARINE & ENVIRONM STUDIES, POB 38, SOLOMONS, MD 20688 USA. NR 26 TC 24 Z9 25 U1 0 U2 3 PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS PI OTTAWA PA 65 AURIGA DR, SUITE 203, OTTAWA, ON K2E 7W6, CANADA SN 0706-652X EI 1205-7533 J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD JUL PY 1991 VL 48 IS 7 BP 1334 EP 1337 PG 4 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA FY950 UT WOS:A1991FY95000025 ER PT J AU FANCY, SG WHITTEN, KR AF FANCY, SG WHITTEN, KR TI SELECTION OF CALVING SITES BY PORCUPINE HERD CARIBOU SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article AB Characteristics of 305 calving sites used by 131 different radio-collared caribou (Rangifer tarandus) cows from the Porcupine herd in northeastern Alaska and the northern Yukon Territory were investigated between 1983 and 1990 to determine the factors influencing calving site selection. Cows selected areas north of the foothills primarily to reduce exposure of calves to predators. Sites dominated by Eriophorum tussocks were selected secondarily for access to newly emerging vegetation. Highest calf mortality occurred in years when snowmelt was relatively late and calving occurred closer to the foothills and in Canada. Industrial development of the coastal plain of the Arctic National Wildlife Refuge could increase calf mortality if calving were displaced south and east of potential development areas. C1 US FISH & WILDLIFE SERV,FAIRBANKS,AK 99701. ALASKA DEPT FISH & GAME,FAIRBANKS,AK 99701. NR 27 TC 36 Z9 40 U1 3 U2 16 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD JUL PY 1991 VL 69 IS 7 BP 1736 EP 1743 DI 10.1139/z91-242 PG 8 WC Zoology SC Zoology GA GP060 UT WOS:A1991GP06000003 ER PT J AU MEYER, RF DEWITT, W AF MEYER, RF DEWITT, W TI WHAT GOODS ALL THAT GUNK SO CHEMTECH LA English DT Article RP MEYER, RF (reprint author), US GEOL SURVEY,955 NATL CTR,RESTON,VA 22092, USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0009-2703 J9 CHEMTECH JI Chemtech PD JUL PY 1991 VL 21 IS 7 BP 432 EP 437 PG 6 WC Chemistry, Applied SC Chemistry GA FW944 UT WOS:A1991FW94400012 ER PT J AU BASU, AR WANG, JW HUANG, WK XIE, GH TATSUMOTO, M AF BASU, AR WANG, JW HUANG, WK XIE, GH TATSUMOTO, M TI MAJOR ELEMENT, REE, AND PB, ND AND SR ISOTOPIC GEOCHEMISTRY OF CENOZOIC VOLCANIC-ROCKS OF EASTERN CHINA - IMPLICATIONS FOR THEIR ORIGIN FROM SUBOCEANIC-TYPE MANTLE RESERVOIRS SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article ID CHEMICAL GEODYNAMICS; BASALTS; OCEAN; EVOLUTION; PACIFIC; HETEROGENEITY; CONSTRAINTS; XENOLITHS; HANNUOBA; GENESIS AB Major- and rare-earth-element (REE) concentrations and U-Th-Pb, Sm-Nd, and Rb-Sr isotope systematics are reported for Cenozoic volcanic rocks from northeastern and eastern China. These volcanic rocks, characteristically lacking the calc-alkaline suite of orogenic belts, were emplaced in a rift system which formed in response to the subduction of the western Pacific plate beneath the eastern Asiatic continental margin. The rocks sampled range from basanite and alkali olivine basalt, through olivine tholeiite and quartz tholeiite, to potassic basalts, alkali trachytes, pantellerite, and limburgite. These rock suites represent the volcanic centers of Datong, Hanobar, Kuandian, Changbaishan and Wudalianchi in northeastern China, and Mingxi in the Fujian Province of eastern China. The major-element and REE geochemistry is characteristic of each volcanic suite broadly evolving through cogenetic magmatic processes. Some of the outstanding features of the isotopic correlation arrays are as follows: (1) Nd-Sr shows an anticorrelation within the field of ocean island basalts, extending from the MORB end-member to an enriched, time-averaged high Rb/Sr and Nd/Sr end-member (EM1), (2) Sr-Pb also shows an anticorrelation, similar to that of Hawaiian and Walvis Ridge basalts, (3) Nd-Pb shows a positive correlation, and (4) the Pb-207/Pb-204 vs Pb-206/Pb-204 plot shows linear arrays parallel to the general trend (NHRL) for MORB on both sides of the geochron, although in the Pb-208/Pb-204 vs Pb-206/Pb-204 plot the linear array is significantly displaced above the NHRL in a pattern similar to that of the oceanic island basalts that show the Dupal signatures. In all isotope correlation patterns, the data arrays define two different mantle components-a MORB-like component and an enriched mantle component. The isotopic data presented here clearly demonstrate the existence of Dupal compositions in the sources of the continental volcanic rocks of eastern China. We suggest that the subcontinental mantle beneath eastern China served as the reservoir for the EMI component, and that the MORB component was either introduced by subduction of the Kula-Pacific Ridge beneath the Asiatic plate in the Late Cretaceous, as proposed by Uyeda and Miyashiro, or by upwellings in the subcontinental asthenosphere due to subduction. C1 ACAD SINICA,INST GEOCHEM,GUIYANG,PEOPLES R CHINA. US GEOL SURVEY,DENVER,CO 80225. RP BASU, AR (reprint author), UNIV ROCHESTER,DEPT GEOL SCI,ROCHESTER,NY 14627, USA. NR 45 TC 246 Z9 292 U1 8 U2 38 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD JUL PY 1991 VL 105 IS 1-3 BP 149 EP 169 DI 10.1016/0012-821X(91)90127-4 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GD519 UT WOS:A1991GD51900012 ER PT J AU SAVINO, JF HENRY, MG AF SAVINO, JF HENRY, MG TI FEEDING RATE OF SLIMY SCULPIN AND BURBOT ON YOUNG LAKE CHARR IN LABORATORY REEFS SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE PREDATION; FORAGING; CONTAMINANTS; SPAWNING; LAKE TROUT; SALVELINUS-NAMAYCUSH; COTTUS-COGNATUS; LOTA-LOTA; GREAT LAKES ID TROUT EGGS; MICHIGAN; DIET; REPRODUCTION; BEHAVIOR; SUPERIOR; ONTARIO; GROWTH; FRY AB Predation and contaminants are two possible factors in the poor recruitment of young lake charr Salvelinus namaycush in the Great Lakes. We measured the feeding rate of slimy sculpins Cottus cognatus and burbot Lota lota on young lake charr (uncontaminated young from eggs of a hatchery brook stock and contaminated young from eggs of Lake Michigan lake charr) in laboratory test chambers with a cobble substrate. The median daily consumption rate of sculpins for all tests was 2 lake charr eggs (N = 22 tests; 95% confidence interval, 0-13) and 2 lake charr free embryos (N = 31 tests; 95% confidence interval, 0-10). Feeding rate did not differ between hatchery and contaminated prey. Slimy sculpins continued to feed on lake charr when another prey organism, the deepwater amphipod Pontoporeia hoyi, was present. Feeding by burbot on free embryos (4-36 d-1) increased as the mobility of young increased, but burbot consumed about 10% of their body weight weekly in free-swimming young (140-380 d-1). Predation on lake charr eggs by sculpins could be considerable over the 100 to 140 d incubation period, and burbot could eat large numbers of free-swimming lake charr as the young fish left the reef. Predation pressure on young lake charr may inhibit rehabilitation of self-sustaining populations of lake charr on some reefs unless a critical egg density has been reached. RP SAVINO, JF (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,1451 GREEN RD,ANN ARBOR,MI 48105, USA. NR 35 TC 26 Z9 27 U1 1 U2 14 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD JUL PY 1991 VL 31 IS 3 BP 275 EP 282 DI 10.1007/BF00000692 PG 8 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA FV721 UT WOS:A1991FV72100005 ER PT J AU SUDEKUM, AE PARRISH, JD RADTKE, RL RALSTON, S AF SUDEKUM, AE PARRISH, JD RADTKE, RL RALSTON, S TI LIFE-HISTORY AND ECOLOGY OF LARGE JACKS IN UNDISTURBED, SHALLOW, OCEANIC COMMUNITIES SO FISHERY BULLETIN LA English DT Article ID FRENCH FRIGATE SHOALS; CORAL-REEF ECOSYSTEM; PRISTIPOMOIDES-FILAMENTOSUS; HAWAIIAN SNAPPER; FISHES; OTOLITHS; PATTERNS; ISLANDS; MODEL; AGE AB The large jack species Caranx ignobilis and Caranx melampygus were collected from the nearly pristine shallow waters of the atolls, reefs, and shoals of the Northwestern Hawaiian Islands. Both species were aged by counting daily otolith increments and validating frequency of otolith deposition by marking captive fish with tetracycline. Growth for each species was well described by a von Bertalanffy relationship. Measured growth of captive C. melampygus was also in agreement. Gravid fish of both species were found only in April-November; peak spawning season for both was about May-August. Reproduction began at approximately 350 mm SL (approximately 2 years old) in C. melampygus and at approximately 600 mm SL (approximately 3 1/2 years old) in C. ignobilis. Fecundity of female C. melampygus varied approximately as the 1.7 power of body weight. Both species were > 90% piscivorous, as judged from combined volume and number of prey and incidence of predation. Crustaceans and cephalopods comprised several percent of the diet of C. ignobilis; both groups were present but less important in C. melampygus. Both jack species ate gastropods in trace amounts. The overall diet of the two species showed moderate overlap: "Pianka's" index of overlap, A(yz) = 0.42. The rate of food consumption for captive C. melampygus was used to estimate the respiratory metabolic coefficient, which in turn was used to estimate respiratory demands for all size-classes of both species. The von Bertalanffy model predicted growth energy, and reproductive energy was estimated from values of the gonadosomatic index. These energy terms were combined to calculate the food consumption required to sustain all size-classes appearing in local catch data. This distribution can be represented by a composite individual for each species consuming a little less than 50 kg/year (C. melampygus) and about 150 kg/year (C. ignobilis). Rough population estimates indicated that at one well-studied atoll, the two species populations combined may eat over 30,000 metric tons of prey per year. These results suggest a quantitatively important trophic role for these top-level carangid predators. C1 UNIV HAWAII,US FISH & WILDLIFE SERV,HAWAII COOPERAT FISHERY RES UNIT,HONOLULU,HI 96822. UNIV HAWAII,SCH OCEAN & EARTH SCI & TECHNOL,HONOLULU,HI 96822. NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,TIBURON LAB,TIBURON,CA 94920. RP SUDEKUM, AE (reprint author), STANFORD UNIV HOSP,DEPT SURG,300 PASTEUR DR,STANFORD,CA 94305, USA. NR 59 TC 64 Z9 69 U1 1 U2 18 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 1991 VL 89 IS 3 BP 493 EP 513 PG 21 WC Fisheries SC Fisheries GA GE375 UT WOS:A1991GE37500012 ER PT J AU SMITH, RL HOWES, BL DUFF, JH AF SMITH, RL HOWES, BL DUFF, JH TI DENITRIFICATION IN NITRATE-CONTAMINATED GROUNDWATER - OCCURRENCE IN STEEP VERTICAL GEOCHEMICAL GRADIENTS SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID NITROUS-OXIDE REDUCTION; ISOTOPE FRACTIONATION; CARBON MINERALIZATION; GRAVEL AQUIFER; ACETYLENE; TRANSPORT; SEDIMENTS; FIXATION; AMMONIUM; KINETICS AB A relatively narrow vertical zone (5-6 m thick) of NO3- containing groundwater was identified using multilevel sampling devices in a sand and gravel aquifer on Cape Cod, MA, USA. The aquifer has been chronically contaminated by surface disposal of treated sewage 0.3 km upgradient from the study area. The NO3- zone was anoxic and contained high concentrations of N2O (16.5-mu-M), suggesting that it was a zone of active denitrification. Denitrifying activity was confirmed with direct measurement using acetylene block incubations with aquifer core material; the peak rate was 2.4 nmol N reduced (g sed)-1 day-1. Concentrations of dissolved inorganic carbon and N2 were close to atmospheric equilibrium in uncontaminated groundwater, but were more than 2 times higher within the contaminant plume. Excess CO2 and N2 suggested in situ formation with a stoichiometry of C and N mineralized via denitrification of 0.8 (C/N). Denitrification within the aquifer resulted in an increase in the natural delta-15 N of NO3- (from + 13.6 to +42.0 parts per thousand) and the N2 produced, with an isotopic enrichment factor, epsilon, of -13.9 parts per thousand. Vertical profiles of NH4+ and delta-N-15 of NH4+ indicated that dissimilatory reduction of NO3- to NH4+ was also occurring, but mass balance calculations indicated that denitrification was the predominant process. These results demonstrate that a combination approach using field mass balance, stable isotope analysis, and laboratory incubations yields useful insight as to the significance of denitrification in aquifer sediments and that closely spaced vertical sampling is necessary to adequately quantify the processes controlling C and N transport and transformation within these environments. C1 WOODS HOLE OCEANOG INST,DEPT BIOL,WOODS HOLE,MA 02543. US GEOL SURVEY,DIV WATER RESOURCES,MS 496,LAKEWOOD,CO 80225. RP SMITH, RL (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,MS 408,LAKEWOOD,CO 80225, USA. RI Smith, Richard/A-6733-2008; Shrestha, Yesha/N-8890-2014 OI Smith, Richard/0000-0002-3829-0125; NR 42 TC 167 Z9 171 U1 5 U2 38 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD JUL PY 1991 VL 55 IS 7 BP 1815 EP 1825 DI 10.1016/0016-7037(91)90026-2 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FY221 UT WOS:A1991FY22100006 ER PT J AU SENDEROV, EE HEARN, PP KUZNETSOVA, TP TOBELKO, KT AF SENDEROV, EE HEARN, PP KUZNETSOVA, TP TOBELKO, KT TI THE STRUCTURAL STATE OF SECONDARY POTASSIUM FELDSPARS AS A FUNCTION OF THEIR CONDITION OF FORMATION SO GEOKHIMIYA LA Russian DT Article ID BRINE MIGRATION; CARBONATE ROCKS AB Results of unit-cell refinement are reported for 16 potassium feldspars (K-feldspars), including authigenic overgrowths and their associated detrital cores, metasomatized clays, altered tuffs, and homogeneous crystals from veins and vug fillings. The analyzed K-feldspars are close in composition to end-member orthoclase in the solid solution series and are characterized, in general, by the absence of strain. The structural state of the secondary K-feldspars varies from maximum microcline to sanidine (0.95 greater-than-or-equal-to greater-than-or-equal-to 2t(i) greater-than-or-equal-to 0.62). Triclinic and monoclinic phases usually occur together when 2t(i) exceeds 0.85-0.90. This work reports the first structural state determinations on purified separates of authigenic overgrowths, which were separated from their detrital cores by air abrasion techniques. The results show that the structural state of secondary overgrowths is not determined by that of the detrital core. It is also concluded that secondary K-feldspars in carbonate rocks are structurally well-ordered due to the low silica supersaturation and high concentration of the precipitating fluids, which facilitate relatively slow growth kinetics and the direct emplacement of Al and Si into growing crystal lattices. C1 US GEOL SURVEY,RESTON,VA 22092. RP SENDEROV, EE (reprint author), VI VERNADSKII GEOCHEM & ANAL CHEM INST,MOSCOW,USSR. NR 24 TC 0 Z9 0 U1 0 U2 0 PU ROSSIISKAYA AKADEMIYA NAUK PI MOSCOW PA SAVELEVSKII PER., 13 OCTOZHENKA, 119034 MOSCOW, RUSSIA SN 0016-7525 J9 GEOKHIMIYA+ JI Geokhimiya PD JUL PY 1991 IS 7 BP 958 EP 971 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GT623 UT WOS:A1991GT62300005 ER PT J AU STEVENS, CH STONE, P BELASKY, P AF STEVENS, CH STONE, P BELASKY, P TI PALEOGEOGRAPHIC AND STRUCTURAL SIGNIFICANCE OF AN UPPER MISSISSIPPIAN FACIES BOUNDARY IN SOUTHERN NEVADA AND EAST-CENTRAL CALIFORNIA SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID VALLEY; GEOLOGY; RANGES AB A major facies boundary separating Meramecian (lower Upper Mississippian) shallow-water, carbonate-platform rocks to the south-east from coeval to slightly younger relatively deep-water siliciclastic rocks to the northwest can be traced throughout southern Nevada and east-central California. Although the precise depositional relation between the two facies is not entirely clear, the outer margin of the shallow-water carbonate rocks almost certainly marks the edge of the carbonate platform in earliest late Meramecian time. This facies boundary is distinct and unambiguous enough that it and a parallel subfacies boundary within the carbonate-platform rocks can be used to estimate amounts of displacement on Cenozoic right-slip faults in the region. The carbonate-siliciclastic facies boundary is offset by about 170 km in a right-lateral sense parallel to the Death Valley-Furnace Creek fault zone between the west side of that fault zone and the northeast side of the Las Vegas Valley shear zone. This offset is Cenozoic in age and is interpreted to be distributed as follows: 45-50 km on the Las Vegas Valley shear zone, 80 km on the Death Valley-Furnace Creek fault zone, 30 km on the Stewart Valley fault, and an additional 10-15 km that is not specifically accounted for. Restoration of these offsets successfully reconstructs the Meramecian carbonate shelf edge and aligns several thrust faults now exposed on opposite sides of the right-slip faults. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP STEVENS, CH (reprint author), SAN JOSE STATE UNIV,DEPT GEOL,SAN JOSE,CA 95192, USA. NR 47 TC 28 Z9 28 U1 0 U2 1 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD JUL PY 1991 VL 103 IS 7 BP 876 EP 885 DI 10.1130/0016-7606(1991)103<0876:PASSOA>2.3.CO;2 PG 10 WC Geosciences, Multidisciplinary SC Geology GA FV903 UT WOS:A1991FV90300003 ER PT J AU VEDDER, JG MCLEAN, H STANLEY, RG WILEY, TJ AF VEDDER, JG MCLEAN, H STANLEY, RG WILEY, TJ TI PALEOGEOGRAPHIC IMPLICATIONS OF AN EROSIONAL REMNANT OF PALEOGENE ROCKS SOUTHWEST OF THE SUR-NACIMIENTO FAULT ZONE, SOUTHERN COAST RANGES, CALIFORNIA SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID WEST-CENTRAL CALIFORNIA AB A small tract of heretofore-unrecognized Paleogene rocks lies about 30 km northeast of Santa Maria and 1 km southwest of the Sur-Nacimiento fault zone near upper Pine Creek. This poorly exposed assemblage of rocks is less than 50 m thick, lies unconformably on regionally distributed Upper Cretaceous submarine-fan deposits, and consists of three units: fossiliferous lower Eocene mudstone, Oligocene(?) conglomerate, and basaltic andesite that has a radiometric age of 26.6 +/- 0.5 Ma. Both the sedimentary and igneous constituents in the Paleogene sequence are unlike those of known sequences on either side of the Sur-Nacimiento fault zone. Conventional paleogeographic restorations need to be modified to accommodate the conditions of deposition and emplacement represented by the three rock units. The Paleogene sedimentary rocks near upper Pine Creek presumably are remnants of formerly widespread early Eocene bathyal deposits and locally distributed Oligocene(?) fluvial deposits southwest of the fault zone. The 26.6 Ma basaltic andesite, however, may not have extended much beyond its present outcrops. Although the history, nature, and amount of pre-Miocene slip along the Sur-Nacimiento fault zone are not resolved, an episode of Oligocene(?) displacement is required by the contrast in thicknesses, depositional patterns, and paleobathymetry of the juxtaposed rock sequences. RP VEDDER, JG (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 999,MENLO PK,CA 94025, USA. NR 41 TC 9 Z9 9 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD JUL PY 1991 VL 103 IS 7 BP 941 EP 952 DI 10.1130/0016-7606(1991)103<0941:PIOAER>2.3.CO;2 PG 12 WC Geosciences, Multidisciplinary SC Geology GA FV903 UT WOS:A1991FV90300009 ER PT J AU HAGSTRUM, JT SEDLOCK, RL AF HAGSTRUM, JT SEDLOCK, RL TI REMAGNETIZATION AND NORTHWARD TRANSLATION OF MESOZOIC RED CHERT FROM CEDROS ISLAND AND THE SAN BENITO ISLANDS, BAJA-CALIFORNIA, MEXICO - REPLY SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Letter ID CRETACEOUS LAYTONVILLE LIMESTONE; FOLD TEST C1 STANFORD UNIV,DEPT GEOL,STANFORD,CA 94305. RP HAGSTRUM, JT (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD JUL PY 1991 VL 103 IS 7 BP 968 EP 969 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FV903 UT WOS:A1991FV90300012 ER PT J AU ZHOU, L KYTE, FT BOHOR, BF AF ZHOU, L KYTE, FT BOHOR, BF TI CRETACEOUS TERTIARY BOUNDARY OF DSDP SITE 596, SOUTH-PACIFIC SO GEOLOGY LA English DT Article ID NEW-ZEALAND; CARAVACA; SPAIN; CLAYS; EVENT AB Sediments from the Cretaceous/Tertiary (K/T) boundary at Deep Sea Drilling Project Site 596 record accumulation of pelagic clays at about lat 45-degrees-S, in the center of the ancestral South Pacific. The K/T boundary in this region is characterized by oxidized, thoroughly bioturbated sediments containing large amounts of Ir and relict high-pressure and high-temperature mineral phases. The net Ir fluence (320 ng cm-2) is among the largest on Earth, and the number of shocked quartz grains > 30-mu-m in size (approximately 1800 cm-2) exceeds that in all localities outside of North America. C1 US GEOL SURVEY,DENVER,CO 80225. RP ZHOU, L (reprint author), UNIV CALIF LOS ANGELES,INST GEOPHYS & PLANETARY PHYS,LOS ANGELES,CA 90024, USA. NR 22 TC 29 Z9 30 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUL PY 1991 VL 19 IS 7 BP 694 EP 697 DI 10.1130/0091-7613(1991)019<0694:CTBODS>2.3.CO;2 PG 4 WC Geology SC Geology GA FV902 UT WOS:A1991FV90200006 ER PT J AU ATWATER, BF YAMAGUCHI, DK AF ATWATER, BF YAMAGUCHI, DK TI SUDDEN, PROBABLY COSEISMIC SUBMERGENCE OF HOLOCENE TREES AND GRASS IN COASTAL WASHINGTON-STATE SO GEOLOGY LA English DT Article ID EARTHQUAKES AB Growth-position plant fossils in coastal Washington State imply a suddenness of Holocene submergence that is better explained by coseismic lowering of the land than by decade- or century-long rise of the sea. These fossils include western red cedar and Sitka spruce whose death probably resulted from estuarine submergence close to 300 yr ago. Rings in eroded, bark-free trunks of the red cedar show that growth remained normal within decades of death. Rings in buried, bark-bearing stumps of the spruce further show normal growth continuing until the year of death. Other growth-position fossils implying sudden submergence include the stems and leaves of salt-marsh grass entombed in tide-flat mud close to 300 yr ago and roughly 1700 and 3100 yr ago. The preservation of these stems and leaves shows that submergence and initial burial outpaced decomposition, which appears to take just a few years in modern salt marshes. In some places the stems and leaves close to 300 yr old are surrounded by sand left by an extraordinary, landward-directed surge-probably a tsunami from a great thrust earthquake on the Cascadia subduction zone. C1 UNIV COLORADO,INST ARCTIC & ALPINE RES,MT RES STN,BOULDER,CO 80309. RP ATWATER, BF (reprint author), UNIV WASHINGTON,US GEOL SURVEY,DEPT GEOL SCI,AJ-20,SEATTLE,WA 98195, USA. NR 22 TC 91 Z9 92 U1 0 U2 11 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUL PY 1991 VL 19 IS 7 BP 706 EP 709 DI 10.1130/0091-7613(1991)019<0706:SPCSOH>2.3.CO;2 PG 4 WC Geology SC Geology GA FV902 UT WOS:A1991FV90200009 ER PT J AU SHANLEY, KW MCCABE, PJ AF SHANLEY, KW MCCABE, PJ TI PREDICTING FACIES ARCHITECTURE THROUGH SEQUENCE STRATIGRAPHY - AN EXAMPLE FROM THE KAIPAROWITS PLATEAU, UTAH SO GEOLOGY LA English DT Article ID SEDIMENTARY AB Recognition of depositional sequences in Upper Cretaceous strata in the Kaiparowits Plateau allows examination of facies-tract geometries within coeval shoreface, alluvial, and coal-bearing strata. Changes in depositional architecture, sandstone-connectedness, sandshale ratios, coal-bed geometry, and degree of shoreface and foreshore preservation are related to position within a depositional sequence. Base-level falls produced regionally extensive sequence boundary unconformities and a basinward shift in facies tracts. Slow rates of base-level rise resulted in amalgamated fluvial channel complexes, thin discontinuous coal beds, and progradational shoreface parasequence sets. More rapid rates of base-level rise produced vertically isolated meander-belt sandstones, thick extensive coal beds, and aggradational shoreface parasequence sets. The highest rates of base-level rise resulted in retrogradational shoreface parasequence and tidally influenced fluvial systems at least 60 km inland of coeval shoreface deposits. C1 US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. RP SHANLEY, KW (reprint author), COLORADO SCH MINES,DEPT GEOL & GEOL ENGN,GOLDEN,CO 80401, USA. OI McCabe, Peter/0000-0001-5262-1018 NR 17 TC 106 Z9 110 U1 1 U2 10 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUL PY 1991 VL 19 IS 7 BP 742 EP 745 DI 10.1130/0091-7613(1991)019<0742:PFATSS>2.3.CO;2 PG 4 WC Geology SC Geology GA FV902 UT WOS:A1991FV90200018 ER PT J AU DAVIS, AS CLAGUE, DA SCHULZ, MS HEIN, JR AF DAVIS, AS CLAGUE, DA SCHULZ, MS HEIN, JR TI LOW SULFUR-CONTENT IN SUBMARINE LAVAS - AN UNRELIABLE INDICATOR OF SUBAERIAL ERUPTION SO GEOLOGY LA English DT Article ID BACK-ARC BASIN; VOLCANIC-ROCKS; ISLAND-ARC; RIDGE; BASALTS; VOLATILES; PETROGENESIS; SOLUBILITY AB Low S content (< 250 ppm) has been used to identify subaerially erupted Hawaiian and Icelandic lavas. Large differences in S content of submarine-erupted lavas from different tectonic settings indicate that the behavior of S is complex. Variations in S abundance in undegassed, submarine-erupted lavas can result from different source compositions, different percentages of partial melting, and crystal fractionation. Low S concentrations in highly vesicular submarine lavas suggest that partial degassing can occur despite great hydrostatic pressure. These processes need to be evaluated before using S content as an indicator of eruption depth. RP DAVIS, AS (reprint author), US GEOL SURVEY,MS-999,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. OI Schulz, Marjorie/0000-0001-5597-6447 NR 30 TC 19 Z9 20 U1 0 U2 1 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUL PY 1991 VL 19 IS 7 BP 750 EP 753 DI 10.1130/0091-7613(1991)019<0750:LSCISL>2.3.CO;2 PG 4 WC Geology SC Geology GA FV902 UT WOS:A1991FV90200020 ER PT J AU GREEN, AU WORTHINGTON, EU PILIPENKO, VA HERZOG, GB KURNEVA, NA AF GREEN, AU WORTHINGTON, EU PILIPENKO, VA HERZOG, GB KURNEVA, NA TI EFFECT OF MAGNETOSPHERIC ALFVEN RESONANCE ON THE SPECTRUM OF PACKETS OF PC3-4 PULSATIONS AT MID LATITUDES SO GEOMAGNETIZM I AERONOMIYA LA Russian DT Article ID OSCILLATIONS C1 US GEOL SURVEY,DENVER,CO 80225. RP GREEN, AU (reprint author), ACAD SCI USSR,INST EARTH PHYS,MOSCOW V-71,USSR. NR 11 TC 1 Z9 1 U1 0 U2 0 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0016-7940 J9 GEOMAGN AERON+ JI Geomagn. Aeron. PD JUL-AUG PY 1991 VL 31 IS 4 BP 619 EP 624 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA GU089 UT WOS:A1991GU08900008 ER PT J AU VANDERHILST, RD ENGDAHL, ER AF VANDERHILST, RD ENGDAHL, ER TI ON ISC PP AND PP DATA AND THEIR USE IN DELAY-TIME TOMOGRAPHY OF THE CARIBBEAN REGION SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article DE CARIBBEAN; DATA ERRORS; DELAY-TIME TOMOGRAPHY; DIFFERENTIAL TRAVEL-TIMES; RESOLUTION ID 3-DIMENSIONAL SEISMIC STRUCTURE; CENTRAL ALEUTIAN EARTHQUAKES; SPARSE LINEAR-EQUATIONS; SUBDUCTION ZONE; LOWER MANTLE; PULSE DISTORTION; LEAST-SQUARES; TRAVEL-TIMES; BODY WAVES; VELOCITY AB A major problem in P delay-time tomography is the inhomogeneous sampling of mantle structure by the P-wave ray paths resulting in low resolution in images of large regions of the upper mantle. Incorporation of PP and pP phases can improve the quality and reliability of tomographic images because they: (1) sample Earth structure not ordinarily sampled by direct P phases; (2) add rays that are oblique to rays of direct phases, which is especially important where the latter sample mantle structure is selected directions; and (3) pP data better constrain the earthquake focal depths. PP traveltimes have often been used in combination with P data in differential traveltime studies. We show that the assumptions and approximations necessary for this approach are problematic, and that they can be avoided when the P, PP and P data are used in tomographic inversion. We investigated the applicability of PP and pP delay times to the tomographic study of the aspherical mantle structure below the Caribbean region. The success of the application of data of the later arriving reflected waves depends critically on the quality of these data. We examined possible sources of error in the ISC PP and pP data and assessed the contribution to the delay times used in this study. For the Caribbean region, analyses of the ISC PP and pP delay times do not reveal biases due to effects of PP-waveform distortions, the asymmetry of the reflections, or due to misidentifications of phases that reflect at a surface other than that assumed. The noise level of PP and pP data is high with respect to data of the direct P-wave. This is accommodated by weighting with the inverse of the variance of the data of each of the three phases. The independent information that is revealed from the PP and pP data results in modifications of tomographic images based solely on P data. These modifications are important if the tomographic images are being used to understand the geodynamical history of convergent margins in the Caribbean region. We investigated the effect of adding data of later arriving phases to the ISC P data with sensitivity tests: we inverted synthetic delay times to which we added Gaussian noise with a standard error typical for the data of the three seismic phases. These tests demonstrate that the image resolution of shallow mantle structure is enhanced significantly by the incorporation of later arriving phases. Due to the absence of seismicity below 200 km the resolution improved less at deeper levels below the Caribbean region. In some poorly constrained parts of the solution the test results even indicate an apparent decrease of resolution. This is explained by changes in the rate of convergence of the inversion algorithm: in mantle regions where the effective sampling of structure improved by the addition of PP- and pP-wave ray paths, the convergence was speeded up at the expense of the convergence rate in regions where fewer or no PP- or pP-wave ray paths were added. A shortcoming of the resolution tests used in our study is that some specific problems of reported delay times are not reflected in synthetic data. We observe that ISC delay times of later arriving phases are not necessarily consistent with the reported hypocentral parameters, as most ISC-reported earthquake locations are computed from direct P-wave data. For the pP data, the inconsistency with event location not only results in a decrease of focal depths during relocation, but in a bias of the imaged velocity perturbations as well. This property of reported data is not modelled in resolution tests. C1 STATE UNIV UTRECHT,DEPT THEORET GEOPHYS,3508 TA UTRECHT,NETHERLANDS. US GEOL SURVEY,DENVER FED CTR,NATL EARTHQUAKE INFORMAT CTR,DENVER,CO 80225. NR 54 TC 36 Z9 36 U1 0 U2 2 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0956-540X J9 GEOPHYS J INT JI Geophys. J. Int. PD JUL PY 1991 VL 106 IS 1 BP 169 EP 188 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FV404 UT WOS:A1991FV40400014 ER PT J AU ANDERSON, WL AF ANDERSON, WL TI APPROXIMATE INVERSION OF HIGH-FREQUENCY ELECTROMAGNETIC SOUNDINGS USING COMPLEX IMAGE THEORY SO GEOPHYSICS LA English DT Article ID HALF-SPACE; FIELD; EARTH AB Electromagnetic (EM) soundings in an intermediate range between quasi-static and radar frequencies (e.g., 30 kHz - 300 MHz) were studied with an approximate inversion method for shallow-layered earth models using complex image theory. The half-space image theory formulas for calculating forward soundings for any dipole source are easily extended to accommodate a multilayered earth, and only involve elementary complex functions. Approximate inversion using the modified image formulas is compared with more exact numerical integration inversion for horizontal-layered models to yield the conductivity, thickness, and dielectric permittivity of each layer. A nonlinear least-squares algorithm was used to obtain parameter and linear parameter error estimates. The results, using known exact forward models and one field data case, indicate that approximate image inversion is more than an order-of-magnitude faster than numerical integration inversion. However, approximate inversion could not always resolve deeper layer parameters as well as with exact inversion. Accuracy of both methods, however, depends on the frequency range used. Nevertheless, approximate inversion can be a useful quick reconnaissance tool, and could easily be written for on-site personal computers. RP ANDERSON, WL (reprint author), US GEOL SURVEY,DENVER FED CTR,GEOPHYS BRANCH,BOX 25046,MS 964,DENVER,CO 80225, USA. NR 16 TC 10 Z9 10 U1 0 U2 1 PU SOC EXPLORATION GEOPHYSICISTS PI TULSA PA 8801 S YALE ST, TULSA, OK 74137 SN 0016-8033 J9 GEOPHYSICS JI Geophysics PD JUL PY 1991 VL 56 IS 7 BP 1087 EP 1092 DI 10.1190/1.1443120 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FW153 UT WOS:A1991FW15300021 ER PT J AU SOLLER, DR AF SOLLER, DR TI APPLYING GIS TO RESOURCE-MANAGEMENT SO GEOTIMES LA English DT Article RP SOLLER, DR (reprint author), US GEOL SURVEY,926 NATL CTR,RESTON,VA 22092, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER GEOLOGICAL INST PI ALEXANDRIA PA 4220 KING ST, ALEXANDRIA, VA 22302-1507 SN 0016-8556 J9 GEOTIMES JI Geotimes PD JUL PY 1991 VL 36 IS 7 BP 16 EP 18 PG 3 WC Geosciences, Multidisciplinary SC Geology GA FW929 UT WOS:A1991FW92900018 ER PT J AU WOLF, SH CELIA, MA HESS, KM AF WOLF, SH CELIA, MA HESS, KM TI EVALUATION OF HYDRAULIC CONDUCTIVITIES CALCULATED FROM MULTIPORT-PERMEAMETER MEASUREMENTS SO GROUND WATER LA English DT Article ID MACROSCOPIC DISPERSION; STOCHASTIC-ANALYSIS; POROUS-MEDIA; TRANSPORT AB A multiport permeameter was developed for use in estimating hydraulic conductivity over intact sections of aquifer core using the core liner as the permeameter body. Six cores obtained from one borehole through the upper 9 m of a stratified glacial-outwash aquifer were used to evaluate the reliability of the permeameter. Radiographs of the cores were used to assess core integrity and to locate 5- to 10-cm sections of similar grain size for estimation of hydraulic conductivity. After extensive testing of the permeameter, hydraulic conductivities were determined for 83 sections of the six cores. Other measurement techniques included permeameter measurements on repacked sections of core, estimates based on grain-size analyses, and estimates based on borehole flowmeter measurements. Permeameter measurements of 33 sections of core that had been extruded, homogenized, and repacked did not differ significantly from the original measurements. Hydraulic conductivities estimated from grain-size distributions were slightly higher than those calculated from permeameter measurements; the significance of the difference depended on the estimating equation used. Hydraulic conductivities calculated from field measurements, using a borehole flowmeter in the borehole from which the cores were extracted, were significantly higher than those calculated from laboratory measurements and more closely agreed with independent estimates of hydraulic conductivity based on tracer movement near the borehole. This indicates that hydraulic conductivities based on laboratory measurements of core samples may underestimate actual field hydraulic conductivities in this type of stratified glacial-outwash aquifer. C1 PRINCETON UNIV,DEPT CIVIL ENGN,PRINCETON,NJ 08544. US GEOL SURVEY,MARLBOROUGH,MA 01752. RP WOLF, SH (reprint author), ENSR CONSULTING & ENGN,35 NAGOG PK,ACTON,MA 01720, USA. NR 28 TC 45 Z9 45 U1 0 U2 9 PU GROUND WATER PUBLISHING CO PI COLUMBUS PA 2600 GROUND WATER WAY, COLUMBUS, OH 43219 SN 0017-467X J9 GROUND WATER JI Ground Water PD JUL-AUG PY 1991 VL 29 IS 4 BP 516 EP 525 DI 10.1111/j.1745-6584.1991.tb00543.x PG 10 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA FU269 UT WOS:A1991FU26900006 ER PT J AU PIERCE, BS STANTON, RW EBLE, CF AF PIERCE, BS STANTON, RW EBLE, CF TI FACIES DEVELOPMENT IN THE LOWER FREEPORT COAL BED, WEST-CENTRAL PENNSYLVANIA, USA SO INTERNATIONAL JOURNAL OF COAL GEOLOGY LA English DT Article ID APPALACHIAN BASIN USA; SWAMP VEGETATION; ILLINOIS AB The Lower Freeport coal bed in west-central Pennsylvania is interpreted to have formed within a lacustrine-mire environment. Conditions of peat formation, caused by the changing chemical and physical environments, produced five coal facies and two mineral-rich parting facies within the coal bed. The coal bed facies are compositionally unique, having developed under varying conditions, and are manifested by megascopic, petrographic, palynologic and quality characteristics. The initial environment of the Lower Freeport peat resulted in a coal facies that is relatively high in ash yield and contains large amounts of lycopod miospores and moderate abundances of crypto-telinite, crypto-gelocollinite, inertinite and tree fem miospores. This initial Lower Freeport peat is interpreted to have been a topogenous body that was low lying, relatively nutrient rich (mesotrophic to eutrophic), and susceptible to ground water and to sediment influx from surface water. The next facies to form was a ubiquitous, clay-rich durain parting which is attributed to a general rise in the water table accompanied by widespread flooding. Following formation of the parting, peat accumulation resumed within an environment that inhibited clastic input. Development of doming in this facies restricted deposition of the upper shale parting to the margins of the mire and allowed low-ash peat to form in the interior of the mire. Because this environment was conducive to preservation of cellular tissue, this coal facies also contains large amounts of crypto-telinite. This facies development is interpreted to have been a transitional phase from topogenous, planar peat formation to slightly domed, oligotrophic (nutrient-poor) peat formation. As domed peat formation continued, fluctuations in the water table enabled oxidation of the peat surface and produced high inertinite concentrations toward the top of the coal bed. Tree ferns became an increasingly important peat contributor in these upper facies, based on the palynoflora. This floral change is interpreted to have resulted from the peat surface becoming less wet or better drained, a condition that inhibited proliferation of lycopod trees. Accumulation of the peat continued until rising water levels formed a freshwater lake within which clays and silts were deposited. The development of the Lower Freeport peat from a planar mire through transitional phases toward domed peat formation may be an example of the type of peat formation of other upper Middle and Upper Pennsylvanian coal beds. RP PIERCE, BS (reprint author), US GEOL SURVEY,956 NATL CTR,RESTON,VA 22092, USA. NR 65 TC 24 Z9 24 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-5162 J9 INT J COAL GEOL JI Int. J. Coal Geol. PD JUL PY 1991 VL 18 IS 1-2 BP 17 EP 43 DI 10.1016/0166-5162(91)90042-H PG 27 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA FX134 UT WOS:A1991FX13400002 ER PT J AU NETHERLAND, MD GREEN, WR GETSINGER, KD AF NETHERLAND, MD GREEN, WR GETSINGER, KD TI ENDOTHALL CONCENTRATION AND EXPOSURE TIME RELATIONSHIPS FOR THE CONTROL OF EURASIAN WATERMILFOIL AND HYDRILLA SO JOURNAL OF AQUATIC PLANT MANAGEMENT LA English DT Article DE HERBICIDE; CHEMICAL CONTROL; ENDOTHALL; BIOMASS; EXPOSURE TIME; EURASIAN WATERMILFOIL; HYDRILLA AB Herbicide concentration and exposure time relationships were determined for endothall (the dipotassium salt of 7-oxabicyclo [2,2,1] heptane-2,3- dicarboxylic acid) and control of Eurasian watermilfoil (Myriopyllum spicatum L.) and dioecious hydrilla (Hydrilla verticillata L. F. Royle) under controlled-environment conditions. Sixteen endothall concentration and exposure time combinations were tested for Eurasian watermilfoil: concentrations ranged from 0.5 to 5.0 mg acid equivalent (ae)/1; exposure times ranged from 2 to 72 hr. Twenty-seven endothall concentration and exposure time combinations were tested for hydrilla: concentrations ranged from 1.0 to 5.0 mg ae/1; exposure times ranged from 6 to 72 hr. Plant control was based on shoot and root biomass harvested at the end of the experiments. Weekly visual injury ratings were used to characterize efficacy during the course of the experiments. Plant control increased (biomass decreased), as either concentration or exposure time increased. A threshold level was reached in which a concentration/exposure time combination provided satisfactory control. Severe Eurasian watermilfoil injury (> 85% biomass reduction) occurred when exposed to 0.5 mg ae/1 for 48 hr, 1.0 mg ae/1 for 36 hr, 3.0 mg ae/1 for 18 hr, and 5.0 mg ae/1 for 12 hr. Severe hydrilla injury (> 85% biomass reduction) occurred when exposed to 2.0 mg ae/1 for 48 hr, and 3.0, 4.0 and 5.0 mg ae/1 for 24 hr. The 1.0 mg ae/1 treatment failed to produce severe hydrilla injury at the maximum exposure time tested of 72 hr. Increased control of Eurasian watermilfoil and hydrilla is likely for treatments in systems where plants remain in contact with endothall concentrations and exposure times greater than the developed threshold levels. C1 US GEOL SURVEY,LITTLE ROCK,AR 72205. RP NETHERLAND, MD (reprint author), USA,ENGN WATERWAYS EXPT STN,ENVIRONM LAB,3909 HALLS FERRY RD,VICKSBURG,MS 39180, USA. NR 12 TC 39 Z9 39 U1 1 U2 4 PU AQUATIC PLANT MANAGEMENT SOC, INC PI CLERMONT PA PO BOX 121086, CLERMONT, FL 34712-1086 SN 0146-6623 J9 J AQUAT PLANT MANAGE JI J. Aquat. Plant Manage. PD JUL PY 1991 VL 29 BP 61 EP 67 PG 7 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA GF535 UT WOS:A1991GF53500001 ER PT J AU ADAMS, CD THURMAN, EM AF ADAMS, CD THURMAN, EM TI FORMATION AND TRANSPORT OF DEETHYLATRAZINE IN THE SOIL AND VADOSE ZONE SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID CO-METABOLISM; ATRAZINE; DEGRADATION AB Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) and two degradation products were monitored at seven depths in the soil and vadose zone throughout the growing season in two experimental plots in which corn (Zea mays L.) was grown. The soils in these plots were a Kimo silty clay loam (clayey over loamy, montmorillonitic, mesic, Fluvaquentic Hapludoll) and a Eudora slit loam (coarse, silty, mixed, mesic, Fluventic Hapludoll). The purpose of this field study was to identify and quantify the mobile and persistent degradation products of atrazine that comprise the input, or "source term," to groundwater resulting from the application of atrazine to the soils. The formation of deethylatrazine (2-amino-4-chloro-6-isopropylamino-s-triazine) and deisopropylatrazine (2-amino-4-chloro-6-ethylamino-s-triazine) was monitored at various depths using suction lysimeters to determine the relative proportions at which these compounds enter the aquifer. Deethylatrazine was the major degradation product of atrazine identified in the soil water and appeared to enter the underlying aquifer at a concentration of 5.0-mu-g/L, which was greater than the concentration of atrazine entering the aquifer. Deisopropylatrazine also was detected in the soil water, but only in minor concentrations relative to atrazine and deethylatrazine. Because deethylatrazine was the major degradation product in the unsaturated zone, the deethylatrazine-to-atrazine ratio (DAR) may be a good indicator of transport of atrazine through the soil. The hypothesis is proposed that the DAR may be used to distinguish point-source from nonpoint-source contamination of an aquifer. C1 US GEOL SURVEY,LAWRENCE,KS 66049. RP ADAMS, CD (reprint author), UNIV KANSAS,DEPT CIVIL ENGN ENVIRONM HLTH ENGN,LAWRENCE,KS 66045, USA. RI Thurman, Earl/B-5131-2011 NR 17 TC 166 Z9 167 U1 0 U2 14 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD JUL-SEP PY 1991 VL 20 IS 3 BP 540 EP 547 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA FZ678 UT WOS:A1991FZ67800007 ER PT J AU GENISE, JF BOWN, TM AF GENISE, JF BOWN, TM TI A REASSESSMENT OF THE ICHNOFOSSIL CHUBUTOLITHES-GAIMANENSIS BOWN AND RATCLIFFE - REPLY SO JOURNAL OF PALEONTOLOGY LA English DT Note C1 US GEOL SURVEY,PALEONTOL & STRATIG BRANCH,DENVER,CO 80225. RP GENISE, JF (reprint author), MUSEO ARGENTINO CIENCIAS NAT BERNARDINO RIVADAVIA,DEPT ENTOMOL,BUENOS AIRES,ARGENTINA. NR 6 TC 3 Z9 3 U1 0 U2 0 PU PALEONTOLOGICAL SOC INC PI ITHACA PA 1259 TRUMANSBURG ROAD, ITHACA, NY 14850 SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD JUL PY 1991 VL 65 IS 4 BP 705 EP 706 PG 2 WC Paleontology SC Paleontology GA FV984 UT WOS:A1991FV98400020 ER PT J AU SEDGWICK, JA KNOPF, FL AF SEDGWICK, JA KNOPF, FL TI PRESCRIBED GRAZING AS A SECONDARY IMPACT IN A WESTERN RIPARIAN FLOODPLAIN SO JOURNAL OF RANGE MANAGEMENT LA English DT Article DE COMMUNITY COMPOSITION; COTTONWOOD LEAVES; FLOODING; LATE-AUTUMN GRAZING; PLANT BIOMASS; POPULUS-SARGENTII ID CATTLE; BOTTOMLAND; BIOMASS; FOREST; BIRDS AB The effect of late-autumn cattle grazing on plant biomass was examined in a western Great Plains cottonwood riparian zone prone to catastrophic flooding every 5-8 years. Following 1 year of pre-treatment data collection in 1982, five 16-ha pastures were grazed from 1982 to 1984 and compared to 5 control pastures within the South Platte River floodplain in northeastern Colorado. At a prescribed grazing level of 0.46 ha/AUM, riparian vegetation proved to be resilient to the impacts of grazing. We detected only a few significant treatment effects for above-ground biomass after succeeding growing seasons. Willows (Salix spp.) responded negatively to grazing whereas biomass of prairie cord-grass (Spartina pectinata Link) was greater on grazed plots. Yearly changes in above-ground biomass, especially dramatic following a severe flood in 1983, suggest that periodic, catastrophic flooding is a major perturbation to the ecosystem, and in conjunction with our results on grazing impacts, indicate that dormant-season grazing within Soil Conservation Service (SCS) guidelines is a comparatively minor impact within the floodplain. In addition, grazing impacts were probably further mitigated by a major forage supplement of cottonwood leaves which was available at the time of cattle introductions. This local forage supplement ultimately created a lighter grazing treatment than that originally prescribed. RP SEDGWICK, JA (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,FT COLLINS,CO 80525, USA. NR 42 TC 18 Z9 18 U1 1 U2 6 PU SOC RANGE MANAGEMENT PI DENVER PA 1839 YORK ST, DENVER, CO 80206 SN 0022-409X J9 J RANGE MANAGE JI J. Range Manage. PD JUL PY 1991 VL 44 IS 4 BP 369 EP 374 DI 10.2307/4002401 PG 6 WC Agriculture, Dairy & Animal Science; Ecology SC Agriculture; Environmental Sciences & Ecology GA FY103 UT WOS:A1991FY10300015 ER PT J AU HINDALL, SM AF HINDALL, SM TI TEMPORAL TRENDS IN FLUVIAL-SEDIMENT DISCHARGE IN OHIO, 1950-1987 SO JOURNAL OF SOIL AND WATER CONSERVATION LA English DT Article AB The U.S. Geological Survey, in cooperation with state, local, and other federal agencies, has been collecting fluvial-sediment data for Ohio streams since April 1950. The amount of data collected, period of data collection, and purpose of the networks have varied over the years. Long-term fluvial-sediment records of annual suspended-sediment-discharge data are available for eight daily suspended-sediment stations operated in Ohio. Graphical and statistical analyses of long-term sediment records indicate that, in general, no long-term (> 3- to 5-year) trends are readily apparent in the relation between annual mean suspended-sediment discharge and water discharge in Ohio; however, some short-term, year-to-year changes in that relation occur for Ohio streams. Double-mass curves for five daily suspended-sediment stations and seasonal Kendall analysis of data from eight daily suspended-sediment stations clearly illustrate the lack of any discernible changes in the suspended-sediment-discharge/water-discharge relation or in suspended-sediment concentration for most Ohio streams over the past 36 years. RP HINDALL, SM (reprint author), US GEOL SURVEY,DIV WATER RESOURCE,COLUMBUS,OH 43212, USA. NR 4 TC 7 Z9 7 U1 0 U2 0 PU SOIL WATER CONSERVATION SOC PI ANKENY PA 7515 N E ANKENY RD, ANKENY, IA 50021-9764 SN 0022-4561 J9 J SOIL WATER CONSERV JI J. Soil Water Conserv. PD JUL-AUG PY 1991 VL 46 IS 4 BP 311 EP 313 PG 3 WC Ecology; Soil Science; Water Resources SC Environmental Sciences & Ecology; Agriculture; Water Resources GA GA402 UT WOS:A1991GA40200025 ER PT J AU PHILLIPS, MK SCHECK, J AF PHILLIPS, MK SCHECK, J TI PARASITISM IN CAPTIVE AND REINTRODUCED RED WOLVES SO JOURNAL OF WILDLIFE DISEASES LA English DT Note DE CAPTIVITY; CANIS-RUFUS; FREE-RANGING; PARASITISM; RED WOLF; REINTRODUCTIONS ID GULF COASTAL PRAIRIES; WILD CANIDS; LOUISIANA; TEXAS AB Fecal examinations revealed that at least 10 of 21 (48%) captive red wolves (Canis rufus) and eight of 12 (67%) free-ranging red wolves were infected with intestinal parasites. No captive wolves and only one of seven reintroduced wolves had dirofilariasis. Ticks were collected from 10 of 21 (48%) captive wolves and nine of 12 (75%) free-ranging animals. Ivermectin administered at a dosage of 50-mu-g/kg of estimated body weight every 30 to 60 days apparently prevented or ameliorated parasitism in red wolves. C1 UNIV FLORIDA,DEPT WILDLIFE & RANGE SCI,GAINESVILLE,FL 32611. RP PHILLIPS, MK (reprint author), US FISH & WILDLIFE SERV,ALLIGATOR RIVER NATL WILDLIFE REFUGE,POB 1969,MANTEO,NC 27954, USA. NR 8 TC 18 Z9 21 U1 1 U2 13 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD JUL PY 1991 VL 27 IS 3 BP 498 EP 501 PG 4 WC Veterinary Sciences SC Veterinary Sciences GA FZ642 UT WOS:A1991FZ64200021 PM 1920674 ER PT J AU JENKS, JA LOCHMILLER, RL LESLIE, DM HELLGREN, EC MELCHIORS, MA MATHIS, GT AF JENKS, JA LOCHMILLER, RL LESLIE, DM HELLGREN, EC MELCHIORS, MA MATHIS, GT TI GLYCOSYLATED HEMOGLOBIN AS A STABLE ALTERNATIVE TO SERUM GLUCOSE IN WHITE-TAILED DEER SO JOURNAL OF WILDLIFE DISEASES LA English DT Note DE BLOOD; GLYCOSYLATED HEMOGLOBIN; ODOCOILEUS-VIRGINIANUS; SERUM GLUCOSE; WHITE-TAILED DEER; NUTRITIONAL CONDITION ID DIABETES-MELLITUS; BLOOD AB We compared serum glucose concentration and percent glycosylated hemoglobin (GH) in captive and wild white-tailed deer (Odocoileus virginianus) to determine stability of glucose relative to GH. Temporal changes in levels of serum glucose and GH were ascertained from serial blood samples collected from three captive deer over a 2-week period. State of glycemia also was determined for 17 wild deer that were collected from three populations in southeastern Oklahoma and southwestern Arkansas (USA). Concentration of serum glucose of captive deer decreased (P = 0.04) from 190.4 to 155.8 mg/dl over the 2 weeks; percent GH did not differ temporally (P = 0.30). Percent GH of wild deer did not differ (P = 0.23) when deer were separated into 2 groups (high and low state of glycemia) based on the median serum glucose concentration. We found a significant difference (P = 0.04) in percent GH among wild deer populations; serum glucose concentration did not differ (P = 0.72) among populations. Our results indicate that percent GH is more stable than serum glucose concentration and may be useful in population comparisons of nutritional condition. C1 TEXAS A&I UNIV,CAESAR KLEBERG WILDLIFE RES INST,KINGSVILLE,TX 78363. WEYER HAEUSER CO,HOT SPRINGS,AR 71902. ARKANSAS GAME & FISH COMMISS,PERRYTOWN,AR 71801. RP JENKS, JA (reprint author), OKLAHOMA STATE UNIV,US FISH & WILDLIFE SERV,OKLAHOMA COOPERAT FISH & WILDLIFE RES UNIT,STILLWATER,OK 74078, USA. RI Jenks, Jonathan/B-7321-2009; OI Hellgren, Eric/0000-0002-3870-472X NR 15 TC 9 Z9 9 U1 0 U2 1 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD JUL PY 1991 VL 27 IS 3 BP 502 EP 505 PG 4 WC Veterinary Sciences SC Veterinary Sciences GA FZ642 UT WOS:A1991FZ64200022 PM 1920675 ER PT J AU HELLGREN, EC VAUGHAN, MR STAUFFER, DF AF HELLGREN, EC VAUGHAN, MR STAUFFER, DF TI MACROHABITAT USE BY BLACK BEARS IN A SOUTHEASTERN WETLAND SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID HABITAT AB We determined habitat use by black bears (Ursus americanus) in the Great Dismal Swamp of Virginia and North Carolina by radiotracking 24 female and 16 male bears. on a year-round basis, females preferred (P < 0.05) pocosins and mesic areas and males preferred gum-cypress (Nyssa spp.-Taxodium distichum) and maple-coniferous (Acer spp.-Pinus spp.) stands. Females preferred (P < 0.05) pocosins and disturbed areas during summer months, mesic and gum-cypress habitats in early fall, and pocosins in late fall. Females used maple-dominated habitats less (P < 0.05) than their availability throughout the year. Roads were preferred (P < 0.05) by females during all seasons except early fall, when females made excursions to feeding areas far from roads. Maintenance and enhancement of pocosins, mature gum, oak (Quercus spp.), and disturbed habitats would benefit black bears in southeastern wetlands by providing a wide variety of natural foods throughout the year. C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT FISHERIES & WILDLIFE SCI,BLACKSBURG,VA 24061. VIRGINIA POLYTECH INST & STATE UNIV,US FISH & WILDLIFE SERV,BLACKSBURG,VA 24061. OI Hellgren, Eric/0000-0002-3870-472X NR 26 TC 31 Z9 33 U1 1 U2 7 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1991 VL 55 IS 3 BP 442 EP 448 DI 10.2307/3808972 PG 7 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA GC878 UT WOS:A1991GC87800011 ER PT J AU SAMUEL, MD RUSCH, DH ABRAHAM, KF GILLESPIE, MM PREVETT, JP AF SAMUEL, MD RUSCH, DH ABRAHAM, KF GILLESPIE, MM PREVETT, JP TI FALL AND WINTER DISTRIBUTION OF CANADA GEESE IN THE MISSISSIPPI FLYWAY SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article AB Canada geese (Branta canadensis) from northern Manitoba and northern Ontario were marked with leg bands and neck bands and observed throughout the Mississippi flyway f rom 1978 to 1989. We used observations of neck-banded geese within each state to determine the relative fall/winter distribution of the Eastern Prairie Population (EPP) and the Mississippi Valley Population (MVP). Mississippi Valley geese were affiliated with states east of the Mississippi River; EPP geese were affiliated with states west of the Mississippi River. However, we found geographic differences in population distribution within several states. Significant annual changes in distribution also occurred in most states. Management of Mississippi flyway geese should consider the differences in both population dynamics and spatial and temporal distributions of MVP and EPP geese in determining state and flyway harvest objectives. C1 UNIV WISCONSIN,WISCONSIN COOPERAT WILDLIFE RES UNIT,MADISON,WI 53706. ONTARIO MINIST NAT RESOURCES,CTR NO FOREST ECOSYST RES,THUNDER BAY P7B 5E1,ONTARIO,CANADA. DEPT NAT RESOURCES,WINNIPEG R3H 0W9,MANITOBA,CANADA. UNIV WISCONSIN,DEPT WILDLIFE ECOL,MADISON,WI 53706. RP SAMUEL, MD (reprint author), US FISH & WILDLIFE SERV,NATL WILDLIFE HLTH RES CTR,6006 SCHROEDER RD,MADISON,WI 53711, USA. NR 32 TC 3 Z9 3 U1 3 U2 4 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1991 VL 55 IS 3 BP 449 EP 456 DI 10.2307/3808973 PG 8 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA GC878 UT WOS:A1991GC87800012 ER PT J AU KREMENTZ, DG STOTTS, VD STOTTS, DB HINES, JE FUNDERBURK, SL AF KREMENTZ, DG STOTTS, VD STOTTS, DB HINES, JE FUNDERBURK, SL TI HISTORICAL CHANGES IN LAYING DATE, CLUTCH SIZE, AND NEST SUCCESS OF AMERICAN BLACK DUCKS SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID SURVIVAL AB The breeding population of American black ducks (Anas rubripes) on Chesapeake Bay has declined over the past 30 years. We tested whether there have been changes in laying date, clutch size, and nest success of breeding black ducks on islands in Chesapeake Bay between the 1950's and 1980's. None of these variables differed significantly between decades, suggesting that other factors must be responsible for the decline in locally breeding black ducks. C1 US FISH & WILDLIFE SERV,CHESAPEAKE BAY ESTUARY PROGRAM,ANNAPOLIS,MD 21401. RP KREMENTZ, DG (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 21 TC 5 Z9 5 U1 1 U2 2 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1991 VL 55 IS 3 BP 462 EP 466 DI 10.2307/3808975 PG 5 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA GC878 UT WOS:A1991GC87800014 ER PT J AU REYNOLDS, RE SAUER, JR AF REYNOLDS, RE SAUER, JR TI CHANGES IN MALLARD BREEDING POPULATIONS IN RELATION TO PRODUCTION AND HARVEST RATES SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID SURVIVAL RATES; MORTALITY AB We used breeding population, band recovery, and hunter harvest data to examine whether rates of productivity and harvest correlated with annual changes in mallard (Anas platyrhynchos) breeding populations. Percent change in the size of the breeding population correlated positively with an index of production rate and negatively with an index of harvest rate (R2 = 0.37, F = 8.34, P < 0.005). Average harvest rate indices did not differ (W = 126, P < 0.32) between periods of increasing (1961-69) and decreasing (1970-85) populations. Indices to production tended to be lower (W = 143, P < 0.08) during 1970-85 (xBAR = 0.964) compared to 1961-69 (xBAR = 1.096). C1 US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. US FISH & WILDLIFE SERV,OFF MIGRATORY BIRD MANAGEMENT,LAUREL,MD 20708. NR 27 TC 17 Z9 17 U1 0 U2 1 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1991 VL 55 IS 3 BP 483 EP 487 DI 10.2307/3808979 PG 5 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA GC878 UT WOS:A1991GC87800018 ER PT J AU WATSON, JW GARRETT, MG ANTHONY, RG AF WATSON, JW GARRETT, MG ANTHONY, RG TI FORAGING ECOLOGY OF BALD EAGLES IN THE COLUMBIA RIVER ESTUARY SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID FOOD-HABITS; PREY; BEHAVIOR; OSPREYS AB We studied time budgets and foraging ecology of adult bald eagles (Haliaeetus leucocephalus) in the Columbia River Estuary from 1984 to 1986. Eagles spent most of their time perching (94%); of that time, loafing (54%), foraging (23%), and nesting activities (16%) were most frequently observed. Eagles acquired food by hunting live prey (57%), scavenging (24%), and pirating (19%). Fish were the most important food and comprised 71% of prey remains. Catostomids, cyprinids, and fish < 30 cm long were most often preyed upon. Consumption of waterfowl and seabirds increased in winter as they became more abundant. Foraging was spatially dependent on the distribution of tidal flats and water < 4 m deep and was most common at low tide and first daylight. Differences in diets among pairs and between seasons reflect a strategy of opportunistic foraging. Management of eagle foraging habitats in the estuary should emphasize protection and enhancement of tidal flats and prey to maximize foraging opportunities. C1 OREGON STATE UNIV,US FISH & WILDLIFE SERV,OREGON COOPERAT WILDLIFE RES UNIT,CORVALLIS,OR 97331. NR 32 TC 34 Z9 35 U1 5 U2 14 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1991 VL 55 IS 3 BP 492 EP 499 DI 10.2307/3808981 PG 8 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA GC878 UT WOS:A1991GC87800020 ER PT J AU SMALL, RJ HOLZWART, JC RUSCH, DH AF SMALL, RJ HOLZWART, JC RUSCH, DH TI PREDATION AND HUNTING MORTALITY OF RUFFED GROUSE IN CENTRAL WISCONSIN SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID SURVIVAL; TELEMETRY; RATES AB We monitored 381 radio-marked ruffed grouse (Bonasa umbellus) on public and private woodlands in central Wisconsin during 1982-88 to determine seasonal mortality rates due to predation and hunting. A total of 222 known mortalities were recorded: 159 from predation and 63 from hunting. Adult survival rates gradually decreased from 0.85 in summer to 0.57 in winter, then increased in spring to 0.73. juvenile survival was also highest in summer (0.61), but remained relatively low through all seasons. Hunting mortality rates on public hunting areas were significantly (P < 0.005) higher than on private lands for both adults (0.73 vs. 0.13) and juveniles (0.56 vs. 0.09). In contrast, mortality (viz., predation) was similar during the nonhunting season on public and private lands for both adults (0.44 vs. 0.44) and juveniles (0.80 vs. 0.77, respectively), suggesting that hunting mortality was at least partially, if not completely, additive to natural mortality. Immigration from private lands sustained grouse numbers on public lands because overall population densities gradually increased from 5.8 to 7.8 drumming males per 100 ha during the 6-year study. We conclude that ruffed grouse numbers will be substantially reduced in areas with high hunting mortality and reduced immigration due to fragmented habitat. C1 UNIV WISCONSIN,US FISH & WILDLIFE SERV,WISCONSIN COOPERAT WILDLIFE RES UNIT,MADISON,WI 53706. RP SMALL, RJ (reprint author), UNIV WISCONSIN,DEPT WILDLIFE ECOL,MADISON,WI 53706, USA. NR 34 TC 49 Z9 49 U1 1 U2 13 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1991 VL 55 IS 3 BP 512 EP 520 DI 10.2307/3808983 PG 9 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA GC878 UT WOS:A1991GC87800022 ER PT J AU LEITNER, LA DUNN, CP GUNTENSPERGEN, GR STEARNS, F SHARPE, DM AF LEITNER, LA DUNN, CP GUNTENSPERGEN, GR STEARNS, F SHARPE, DM TI EFFECTS OF SITE, LANDSCAPE FEATURES, AND FIRE REGIME ON VEGETATION PATTERNS IN PRESETTLEMENT SOUTHERN WISCONSIN SO LANDSCAPE ECOLOGY LA English DT Article DE DISTURBANCE; FIRE; HETEROGENEITY; LANDSCAPE PATTERN; TOPOGRAPHY; WISCONSIN AB The presettlement tree cover (1831-33) of 3 townships in a southern Wisconsin landscape was analyzed using original survey records. Four forest types were identified: closed forest, open forest, savanna, and prairie. Comparisons of vegetation types and landscape pattern were made between the east and west sides of the Pecatonica River, which bisects the landscape and could have acted as a natural fire barrier. West of the river, presettlement tree species richness and diversity were lower and trees were smaller in diameter and less dense than to the east. The major vegetation types to the west were prairie (42% of landscape) and savanna (40%), both fire-susceptible types. Prairie was more common on gentle slopes than on other landforms. To the east, the landscape was 70% forested (closed plus open forest). Here, prairie was more frequent on steep dry sites. These vegetation differences, including the contrasting landscape placement of prairie, are attributed to distinct site characteristics and to disturbance (fire) regimes, with the west likely having more frequent fires. In terms of the four vegetation types, the east landscape was more homogeneous, being dominated by closed forest (50%). West of the Pecatonica River, the landscape was more heterogeneous because of the high proportion of both prairie and savanna; however, in terms of flammability of vegetation, the west was essentially homogeneous (82% prairie plus savanna). C1 ARGONNE NATL LAB, DIV ENVIRONM ASSESSMENT & INFORMAT SCI, ARGONNE, IL 60439 USA. US FISH & WILDLIFE SERV, NATL WETLANDS RES CTR, SLIDELL, LA 70458 USA. N CENT FOREST EXPT STN, FORESTRY SCI LAB, RHINELANDER, WI 54501 USA. SO ILLINOIS UNIV, DEPT GEOG, CARBONDALE, IL 62901 USA. RP LEITNER, LA (reprint author), UNIV WISCONSIN, DEPT BIOL SCI, POB 413, MILWAUKEE, WI 53201 USA. NR 0 TC 45 Z9 46 U1 0 U2 8 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0921-2973 J9 LANDSCAPE ECOL JI Landsc. Ecol. PD JUL PY 1991 VL 5 IS 4 BP 203 EP 217 DI 10.1007/BF00141435 PG 15 WC Ecology; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA GG213 UT WOS:A1991GG21300002 ER PT J AU MCKNIGHT, DM AIKEN, GR SMITH, RL AF MCKNIGHT, DM AIKEN, GR SMITH, RL TI AQUATIC FULVIC-ACIDS IN MICROBIALLY BASED ECOSYSTEMS - RESULTS FROM 2 DESERT LAKES IN ANTARCTICA SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Note ID HUMIC SUBSTANCES; STREAM AB We characterized fulvic acids from two Antarctic lakes to determine the chemical characteristics of dissolved fulvic acid derived from organic material of microbial origin. These lakes receive very limited inputs of organic material from the surrounding barren desert, but they sustain algal and bacterial populations under permanent ice cover. One lake has an extensive anoxic zone and high salinities; the other is oxic and has low salinities. Despite these differences, fulvic acids from both lakes had similar elemental compositions, carbon distributions, and amino acid contents, indicating that the chemistry of microbially derived fulvic acids is not strongly influenced by chemical conditions in the water column. Compared to fulvic acids from other natural waters, these fulvic acids have low C: N atomic ratios (19-25) and low contents of aromatic carbons (5-7% of total carbon atoms); they are most similar to marine fulvic acids. RP MCKNIGHT, DM (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,POB 25046,MS 408,LAKEWOOD,CO 80225, USA. RI Smith, Richard/A-6733-2008; OI Smith, Richard/0000-0002-3829-0125; MCKNIGHT, DIANE/0000-0002-4171-1533 NR 18 TC 93 Z9 95 U1 0 U2 13 PU AMER SOC LIMNOLOGY OCEANOGRAPH PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD JUL PY 1991 VL 36 IS 5 BP 998 EP 1006 PG 9 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA GP594 UT WOS:A1991GP59400014 ER PT J AU SIPKIN, SA NEEDHAM, RE AF SIPKIN, SA NEEDHAM, RE TI MOMENT-TENSOR SOLUTIONS ESTIMATED USING OPTIMAL FILTER THEORY - GLOBAL SEISMICITY, 1988-1989 SO PHYSICS OF THE EARTH AND PLANETARY INTERIORS LA English DT Article ID COUPLE EARTHQUAKE MECHANISMS; SOURCE PARAMETERS; WAVEFORM DATA; INVERSION AB Moment-tensor solutions, estimated using optimal filter theory, are listed for 201 moderate-to-large earthquakes occurring from 1988 to 1989. RP SIPKIN, SA (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 967,BOX 25046,DENVER,CO 80225, USA. NR 11 TC 20 Z9 20 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-9201 J9 PHYS EARTH PLANET IN JI Phys. Earth Planet. Inter. PD JUL PY 1991 VL 67 IS 3-4 BP 221 EP 230 DI 10.1016/0031-9201(91)90019-E PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FX911 UT WOS:A1991FX91100002 ER PT J AU RACH, JJ DAWSON, VK AF RACH, JJ DAWSON, VK TI ASPECTS OF THE LIFE-HISTORY OF THE CALICO CRAYFISH WITH SPECIAL REFERENCE TO EGG HATCHING SUCCESS SO PROGRESSIVE FISH-CULTURIST LA English DT Article AB Life history data were collected on adult (greater-than-or-equal-to 25 mm carapace length) female calico crayfish (Orconectes immunis) in conjunction with an egg-hatching study during 1986-1988. Eggs stripped from 10 females in October 1986 and 10 females in September 1987 were pooled each year and hatching success was monitored for samples of 100 eggs placed in each of eight diluter aquaria at 12-degrees-C. In fall 1987, berried calico crayfish were cultured at 12, 25, and 30-degrees-C and hatching was monitored. Data on length, weight, and number of eggs produced were collected for 28 females in September 1987 and 36 females in April 1988. An additional 456 female crayfish were checked for the presence of eggs. Hatching success was 86% in 1986 and 89% in 1987. The eggs on berried females held at 12-degrees-C started to hatch within 33 d. At 25-degrees-C, hatching started within 10 d. At 30-degrees-C, no hatching occurred, the eggs became orange (indicating death), and most of the eggs later developed fungal infections. The average number of eggs carried was significantly higher in fall 1987 (153 +/- 80 SD) than in spring 1988 (105 +/- 96). Of 456 females examined in spring 1988, nearly 84% were berried, but 21% bore 20 or fewer eggs. The condition of the ovaries of 23 females that were not carrying eggs suggested that the eggs were being reabsorbed. RP RACH, JJ (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,POB 818,LA CROSSE,WI 54602, USA. NR 19 TC 1 Z9 2 U1 1 U2 6 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 141 EP 145 DI 10.1577/1548-8640(1991)053<0141:AOTLHO>2.3.CO;2 PG 5 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900002 ER PT J AU HERMAN, RL KINCAID, HL AF HERMAN, RL KINCAID, HL TI EFFECTS OF ORALLY-ADMINISTERED STEROIDS ON LAKE TROUT AND ATLANTIC SALMON SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID GROWTH PROMOTION; RAINBOW-TROUT; ESTRADIOL AB Lake trout (Salvelinus namaycush) and Atlantic salmon (Salmo salar) fed 30 mg beta-estradiol/kg of feed for 100 d from first feeding had liver and kidney pathology similar to but much less severe than that previously reported for rainbow trout (Oncorhynchus mykiss). Mortality was not affected. Both lake trout and Atlantic salmon treated with estradiol weighed significantly less than control fish at the end of the treatment period and at 200 d posttreatment. Testosterone-treated fish or both species weighed less than control fish at the end of the treatment period. By day 200 posttreatment, testosterone-treated and untreated lake trout weighed the same, but testosterone-treated Atlantic salmon were heavier than control fish. Estradiol treatment produced an all-female population of Atlantic salmon but not of lake trout. Testosterone at 5 mg/kg feed increased the ratio of males to females in both species. C1 US FISH & WILDLIFE SERV,NATL FISHERY RES & DEV LAB,WELLSBORO,PA 16901. RP HERMAN, RL (reprint author), US FISH & WILDLIFE SERV,NATL FISH HLTH RES LAB,POB 700,KEARNEYSVILLE,WV 25430, USA. NR 12 TC 5 Z9 5 U1 1 U2 1 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 157 EP 161 PG 5 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900005 ER PT J AU KINDSCHI, GA BARROWS, FT AF KINDSCHI, GA BARROWS, FT TI EVALUATION OF AN ELECTRONIC COUNTER FOR WALLEYE FRY SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID INTENSIVE CULTURE; LARVAL WALLEYES; MORTALITY; EGGS AB We evaluated an electronic fry counter (Jensorter, Inc., model FC 2) for accuracy, precision, ease of use, and effects on survival of walleye fry (Stizostedion vitreum). Average electronic counts of fry differed from hand counts by no more than 4.9%; fry numbers estimated volumetrically differed from hand counts by 90.2% and from gravimetric estimates by 17.2%. Survival of electronically counted walleye fry after 66 h (96.7%) did not differ significantly (P > 0.05) from survival of fry counted by hand (97.1%), gravimetrically (97.4%), or volumetrically (97.8%). The electronic counter records debris as well as fry, so the water must be free of egg fragments, sediment, and other particles. With this constraint, the electronic counter was easy to use, faster than hand counts, and more accurate than gravimetric and volumetric methods of enumeration. Its effect on survival was low. The device may be useful for counting larvae of other species besides walleye. RP KINDSCHI, GA (reprint author), US FISH & WILDLIFE SERV,BOZEMAN FISH TECHNOL CTR,4050 BRIDGER CANYON RD,BOZEMAN,MT 59715, USA. NR 14 TC 4 Z9 4 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 180 EP 183 DI 10.1577/1548-8640(1991)053<0180:EOAECF>2.3.CO;2 PG 4 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900010 ER PT J AU HUNN, JB GREER, IE AF HUNN, JB GREER, IE TI INFLUENCE OF SAMPLING ON THE BLOOD-CHEMISTRY OF ATLANTIC SALMON SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID RAINBOW-TROUT; GAIRDNERI RICHARDSON; SALAR L; TEMPERATURE; CORTISOL; STRESS AB Blood samples were taken from laboratory-reared Atlantic salmon (Salmo salar) to determine the physiological status of the fish. The Atlantic salmon were also subjected to one of eight treatments before blood sampling to determine the influence of various handling stresses on the blood analyses. Treatments included holding the fish in nets in water or air for 2 or 4 min, or anesthesia with benzocaine, benzocaine hydrochloride, or tricaine for 3 min. Fish stunned by a blow to the head were used as controls. These treatments resulted in no major changes in selected blood chemistry characteristics: hematocrit, plasma glucose and chloride levels, and osmolality. Atlantic salmon exhibit a limited stress response to netting, as indicated by minor changes in plasma glucose concentrations. RP HUNN, JB (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,ROUTE 2,4200 NEW HAVEN RD,COLUMBIA,MO 65201, USA. NR 20 TC 15 Z9 15 U1 3 U2 6 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 184 EP 187 DI 10.1577/1548-8640(1991)053<0184:IOSOTB>2.3.CO;2 PG 4 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900011 ER PT J AU ZITZOW, RE AF ZITZOW, RE TI EXTENDED INCUBATION OF WALLEYE EGGS WITH LOW-FLOW INCUBATORS SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB Dechlorinated city water and low-flow fish egg incubators were used successfully to extend the incubation period of eggs from walleyes (Stizostedion vitreum) and produce healthy fry. Delaying the hatch of walleye eggs provides an opportunity to produce a second crop of fingerlings in a drainable earthen pond ir one season. C1 US FISH & WILDLIFE SERV,VALLEY CITY NATL FISH HATCHERY,VALLEY CITY,ND 58072. NR 1 TC 1 Z9 1 U1 0 U2 2 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 188 EP 189 DI 10.1577/1548-8640(1991)053<0188:TNEIOW>2.3.CO;2 PG 2 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900012 ER PT J AU LIU, HW STICKNEY, RR SMITH, SD AF LIU, HW STICKNEY, RR SMITH, SD TI A NOTE ON THE ARTIFICIAL SPAWNING OF PACIFIC HALIBUT SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB Adult Pacific halibut (Hippoglossus stenolepis) taken from the wild were held in captivity beginning in 1986. The first successful captive spawning with subsequent development of Pacific halibut larvae in the USA was conducted during February and March 1988. One of the eight larvae produced survived for 6 d, by which time eye pigment was visible. C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,SEATTLE,WA 98115. RP LIU, HW (reprint author), UNIV WASHINGTON,SCH FISHERIES,SEATTLE,WA 98195, USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 189 EP 192 PG 4 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900013 ER PT J AU MASON, WT NOBLE, JD ALLEMAND, RP AF MASON, WT NOBLE, JD ALLEMAND, RP TI AN UNDERWATER VIEWING TUBE SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB A viewing device is described for observing fish in turbid water, using diving weights to control buoyancy and a waterproof flashlight for improved viewing. RP MASON, WT (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,7920 N W 71ST ST,GAINESVILLE,FL 32606, USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD JUL PY 1991 VL 53 IS 3 BP 198 EP 199 DI 10.1577/1548-8640(1991)053<0198:AUVT>2.3.CO;2 PG 2 WC Fisheries SC Fisheries GA GQ649 UT WOS:A1991GQ64900016 ER PT J AU HEALY, RW MILLS, PC AF HEALY, RW MILLS, PC TI VARIABILITY OF AN UNSATURATED SAND UNIT UNDERLYING A RADIOACTIVE-WASTE TRENCH SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID SOIL HYDRAULIC-PROPERTIES; SOLUTE TRANSPORT; PHYSICAL-PROPERTIES; WATER MOVEMENT; CONDUCTIVITY; DRAINAGE; MODELS; INFILTRATION; MOISTURE; TEXTURE AB Properties of soils vary considerably within any field. This study was conducted to investigate the variability in properties of an unsaturated sand unit that lies at a depth of 13 m below land surface. Four-hundred-forty soil core samples, obtained from a 1.75 by 18-m horizontal plane within a sand unit underlying a waste trench, were used to describe the variability of moisture content, tritium concentration, and several physical properties. A simple model based on unit-gradient theory was used to calculate fluxes of water and tritium through the study plane. The effects of including spatial variability of properties in model calculations were examined. The sand was uniform in terms of median particle size, bulk density, and porosity, but several variables, including saturated hydraulic conductivity (K(s)) and tritium concentration, showed considerable variability. In general, correlation coefficients calculated between variables were low. Spatial correlation structures were identified for moisture content, tritium concentration, and a few particle-size variables, but were absent for K(s) and most other variables. Variances of K(s) and field-measured volumetric moisture content (theta) were lower than published values for soils. Model-calculated fluxes of water and tritium that accounted for spatial variability of properties were considerably higher than those that did not account for the variability. Model results were more sensitive to changes in theta and residual moisture content (each parameters of the relative hydraulic conductivity function) than to changes in K(s). C1 US GEOL SURVEY,DIV WATER RESOURCES,URBANA,IL 61801. RP HEALY, RW (reprint author), US GEOL SURVEY,DENVER FED CTR,DIV WATER RESOURCES,MS 413,POB 25046,DENVER,CO 80225, USA. NR 45 TC 11 Z9 12 U1 0 U2 2 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD JUL-AUG PY 1991 VL 55 IS 4 BP 899 EP 907 PG 9 WC Soil Science SC Agriculture GA GC436 UT WOS:A1991GC43600001 ER PT J AU ANDRASKI, BJ AF ANDRASKI, BJ TI BALLOON AND CORE SAMPLING FOR DETERMINING BULK-DENSITY OF ALLUVIAL DESERT SOIL SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Note ID CALIBRATION AB Samples were collected from major strata in the upper 5 m of an alluvial soil profile in the Amargosa Desert of southern Nevada to compare rubber-balloon and drive-core bulk-density measurement methods. For strata where the fine soil was < 82% sand and < 15% clay, differences between total and fine-soil bulk-density values determined by the two methods were typically < 10 and 15%, respectively, even where rock-fragment content was as great as 48% by volume. Outside this range of fine-soil texture, where soil consistency was either very loose or very hard, the core method appeared to sample inaccurately, resulting in bulk-density values > 0.30 Mg m-3 less than those determined by the balloon method. Under the severe sampling conditions encountered, large decreases in the relative accuracy of the core method were not directly related to rock-fragment content, but were related to extremes in the cohesiveness of the strata sampled. RP ANDRASKI, BJ (reprint author), US GEOL SURVEY,705 N PL ST,CARSON CITY,NV 89701, USA. NR 8 TC 18 Z9 18 U1 0 U2 3 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD JUL-AUG PY 1991 VL 55 IS 4 BP 1188 EP 1190 PG 3 WC Soil Science SC Agriculture GA GC436 UT WOS:A1991GC43600048 ER PT J AU POE, TP HANSEL, HC VIGG, S PALMER, DE PRENDERGAST, LA AF POE, TP HANSEL, HC VIGG, S PALMER, DE PRENDERGAST, LA TI FEEDING OF PREDACEOUS FISHES ON OUT-MIGRATING JUVENILE SALMONIDS IN JOHN-DAY-RESERVOIR, COLUMBIA RIVER SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID NORTHERN SQUAWFISH PTYCHOCHEILUS; STIZOSTEDION-VITREUM-VITREUM; FAST-START PERFORMANCE; GAS SUPERSATURATION; SIZE; PREY; STEELHEAD; OREGONENSIS; CONSUMPTION; ABUNDANCE AB Diets of northern squawfish Ptychocheilus, smallmouth bass Micropterus dolomieu, walleye Stizostedion vitreum, and channel catfish Ictalurus punctatus from John Day Reservoir were examined to determine the extent of predation on juvenile salmonids during seaward migrations of the salmonids during April-August 1983-1986. Juvenile Pacific salmon Oncorhynchus spp. and steelhead O. mykiss were the most important food group (by weight) of northern squawfish-about 67%-but made up smaller proportions of the food of the other predators: channel catfish, 33%; walleyes, 14%; smallmouth bass, 4%. Seasonal changes in diets indicated that northern squawfish preferred juvenile salmonids in May and August (generally the peak period of salmonid out-migration), and switched to prickly sculpin Cottus asper when numbers of juvenile salmonids declined; walleyes and smallmouth bass showed a preference only for prickly sculpin among the prey fishes analyzed. As judged by dietary composition and prey selectivity, the northern squawfish was the major fish predator on juvenile salmonids in the reservoir; channel catfish also were important predators in the upper reservoir in spring. Walleyes and smallmouth bass were much less important predators on salmonids, and appeared to select subyearling chinook salmon only in August when the distribution of this prey overlapped with that of the predators. Size-selective predation by northern squawfish may also play an important role in reducing survival of the smaller individuals within each run of out-migrating juvenile salmonids. RP POE, TP (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,SEATTLE COLUMBIA RIVER FIELD STN,COOK,WA 98605, USA. NR 60 TC 90 Z9 92 U1 2 U2 13 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD JUL PY 1991 VL 120 IS 4 BP 405 EP 420 DI 10.1577/1548-8659(1991)120<0405:FOPFOO>2.3.CO;2 PG 16 WC Fisheries SC Fisheries GA GC662 UT WOS:A1991GC66200001 ER PT J AU VIGG, S POE, TP PRENDERGAST, LA HANSEL, HC AF VIGG, S POE, TP PRENDERGAST, LA HANSEL, HC TI RATES OF CONSUMPTION OF JUVENILE SALMONIDS AND ALTERNATIVE PREY FISH BY NORTHERN SQUAWFISH, WALLEYES, SMALLMOUTH BASS, AND CHANNEL CATFISH IN JOHN-DAY-RESERVOIR, COLUMBIA RIVER SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID STIZOSTEDION-VITREUM-VITREUM; FOOD-CONSUMPTION; LARGEMOUTH BASS; FEEDING-BEHAVIOR; CANADENSE; SAUGER; LAKE; AVAILABILITY; REQUIREMENTS; TEMPERATURE AB Adult northern squawfish Ptychocheilus oregonensis, walleyes Stizostedion vitreum, smallmouth bass Micropterus dolomieu, and channel catfish Ictalurus punctatus were sampled from four regions of John Day Reservoir from April to August 1983-1986 to quantify their consumption of 13 species of prey fish, particularly seaward-migrating juvenile Pacific salmon and steelhead (Oncorhynchus spp.). Consumption rates were estimated from field data on stomach contents and digestion rate relations determined in previous investigations. For each predator, consumption rates varied by reservoir area, month, time of day, and predator size or age. The greatest daily consumption of salmonids by northern squawfish and channel catfish (0.7 and 0.5 prey/predator) occurred in the upper end of the reservoir below McNary Dam. Greatest daily predation by walleyes (0.2 prey/predator) and smallmouth bass (0.04) occurred in the middle and lower reservoir. Consumption rates of all predators were highest in July, concurrent with maximum temperature and abundance of juvenile salmonids. Feeding by the predators tended to peak after dawn (0600-1200 hours) and near midnight (2000-2400). Northern squawfish below McNary Dam exhibited this pattern, but fed mainly in the morning hours down-reservoir. The daily ration of total prey fish was highest for northern squawfish over 451 mm fork length (> 13.2 mg/g predator), for walleyes 201-250 mm (42.5 mg/g), for smallmouth bass 176-200 mm (30.4 mg/g), and for channel catfish 401-450 mm (17.1 mg/g). Averaged over all predator sizes and sampling months (April-August), the total daily ration (fish plus other prey) of smallmouth bass (28.7 mg/g) was about twice that of channel catfish (12.6), northern squawfish (14.1), and walleyes (14.2). However, northern squawfish was clearly the major predator on juvenile salmonids. C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,SEATTLE COLUMBIA RIVER FIELD STN,COOK,WA 98605. NR 61 TC 73 Z9 76 U1 3 U2 18 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD JUL PY 1991 VL 120 IS 4 BP 421 EP 438 DI 10.1577/1548-8659(1991)120<0421:ROCOJS>2.3.CO;2 PG 18 WC Fisheries SC Fisheries GA GC662 UT WOS:A1991GC66200002 ER PT J AU RIEMAN, BE BEAMESDERFER, RC VIGG, S POE, TP AF RIEMAN, BE BEAMESDERFER, RC VIGG, S POE, TP TI ESTIMATED LOSS OF JUVENILE SALMONIDS TO PREDATION BY NORTHERN SQUAWFISH, WALLEYES, AND SMALLMOUTH BASS IN JOHN-DAY-RESERVOIR, COLUMBIA RIVER SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID PTYCHOCHEILUS-OREGONENSIS; CONSUMPTION; DIGESTION AB We estimated the loss of juvenile salmonids Oncorhynchus spp. to predation by northern squawfish Ptychocheilus oregonensis, walleyes Stizostedion vitreum, and smallmouth bass Micropterus dolomieu in John Day Reservoir during 1983-1986. Our estimates were based on measures of daily prey consumption, predator numbers, and numbers of juvenile salmonids entering the reservoir during the April-August period of migration. We estimated the mean annual loss was 2.7 million juvenile salmonids (95% confidence interval, 1.9-3.3 million). Northern squawfish were responsible for 78% of the total loss; walleyes accounted for 13% and smallmouth bass for 9%. Twenty-one percent of the loss occurred in a small area immediately below McNary Dam at the head of John Day Reservoir. We estimated that the three predator species consumed 14% (95% confidence interval, 9-19%) of all juvenile salmonids that entered the reservoir. Mortality changed by month and increased late in the migration season. Monthly mortality estimates ranged from 7% in June to 61% in August. Mortality from predation was highest for chinook salmon O. tshawytscha, which migrated in July and August. Despite uncertainties in the estimates, it is clear that predation by resident fish predators can easily account for previously unexplained mortality of out-migrating juvenile salmonids. Alteration of the Columbia River by dams and a decline in the number of salmonids could have increased the fraction of mortality caused by predation over what it was in the past. C1 OREGON DEPT FISH & WILDLIFE,CLACKAMAS,OR 97015. US FISH & WILDLIFE SERV,NATL FISHERY RES CTR,SEATTLE COLUMBIA RIVER FIELD STN,COOK,WA 98605. NR 46 TC 103 Z9 108 U1 1 U2 15 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD JUL PY 1991 VL 120 IS 4 BP 448 EP 458 DI 10.1577/1548-8659(1991)120<0448:ELOJST>2.3.CO;2 PG 11 WC Fisheries SC Fisheries GA GC662 UT WOS:A1991GC66200004 ER PT J AU HOSTETLER, SW AF HOSTETLER, SW TI ANALYSIS AND MODELING OF LONG-TERM STREAM TEMPERATURES ON THE STEAMBOAT CREEK BASIN, OREGON - IMPLICATIONS FOR LAND-USE AND FISH HABITAT SO WATER RESOURCES BULLETIN LA English DT Article DE TIME SERIES ANALYSIS; MODELING STATISTICS; FOREST HYDROLOGY; WATERSHED MANAGEMENT WILDLAND HYDROLOGY; SURFACE WATER HYDROLOGY AB Steamboat Creek basin is an important source of timber and provides crucial spawning and rearing habitat for anadromous steelhead trout (Oncorhynchus mykiss). Because stream temperatures are near the upper limit of tolerance for the survival of juvenile steelhead, the possible long-term effect of clear-cut logging on stream temperatures was assessed. Twenty-year (1969-1989) records of summer stream temperature and flow from four tributaries and two reaches of Steamboat Creek and Boulder Creek (a nearby unlogged watershed) were analyzed. Logging records for the Steamboat Creek basin and air temperature records also were used in the analysis. A time-series model of the components of stream temperature (seasonal cycle of solar radiation, air temperature, streamflow, an autoregressive term of order 1, and a linear trend variable) was fitted to the water-temperature data. The linear trend variable was significant in all the fitted models except Bend Creek (a tributary fed by cool ground-water discharge) and Boulder Creek. Because no trends in either climate (i.e., air temperature) or streamflow were found in the data, the trend variable was associated with the pre-1969 loss and subsequent regrowth of riparian vegetation and shading canopies. RP HOSTETLER, SW (reprint author), US GEOL SURVEY,NATL CTR ATMOSPHER RES,POB 3000ML,BOULDER,CO 80307, USA. NR 15 TC 32 Z9 32 U1 0 U2 6 PU AMER WATER RESOURCES ASSOC PI HERNDON PA 950 HERNDON PARKWAY SUITE 300, HERNDON, VA 20170-5531 SN 0043-1370 J9 WATER RESOUR BULL JI Water Resour. Bull. PD JUL-AUG PY 1991 VL 27 IS 4 BP 637 EP 647 PG 11 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA GZ740 UT WOS:A1991GZ74000007 ER PT J AU PHILPOTTS, J TATSUMOTO, M LI, XH WANG, KY AF PHILPOTTS, J TATSUMOTO, M LI, XH WANG, KY TI SOME ND AND SR ISOTOPIC SYSTEMATICS FOR THE REE-ENRICHED DEPOSIT AT BAYAN OBO, CHINA SO CHEMICAL GEOLOGY LA English DT Article AB Sm-Nd and Rb-Sr isotopic systematics have been determined for rare-earth element (REE) rich samples of carbonate, iron ore, and silicate types from the world's largest known REE deposit at Bayan Obo, China. The results yielded neither Rb-Sr nor Sm-Nd isochrons within analytical error. Isochronous relationships may have been disturbed in part by younger events. Modes in isotopic composition suggest two Sr reservoirs; the low Sr-87/Sr-86 ratios of 0.703 and 0.704 measured for two carbonates may be of mantle origin. The Sm-Nd data delineate a trend at approximately 1 Ga; this trend might represent a disturbed fractionation event or mixing of Nd reservoirs. The REE ores could not have formed in a single fractionation event during the igneous activity at 260 Ma. Model ages suggest that the ore REE were isolated from mantle sources between approximately 1.7 and approximately 1.3 Ga. This time period hosts major anorogenic igneous activity, including anorthosites, and a number of other unusual REE iron ores. C1 US GEOL SURVEY,DENVER,CO 80225. CHINESE ACAD SCI,INST GEOL,BEIJING,PEOPLES R CHINA. ACAD SINICA,INST GEOCHEM,KUANZHOU,PEOPLES R CHINA. RP PHILPOTTS, J (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 22 TC 22 Z9 25 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD JUN 25 PY 1991 VL 90 IS 3-4 BP 177 EP 188 DI 10.1016/0009-2541(91)90098-C PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FX144 UT WOS:A1991FX14400001 ER PT J AU JACKSON, LL FRIES, TL GROSSMAN, JN KING, BSW LAMOTHE, PJ AF JACKSON, LL FRIES, TL GROSSMAN, JN KING, BSW LAMOTHE, PJ TI GEOLOGICAL AND INORGANIC MATERIALS SO ANALYTICAL CHEMISTRY LA English DT Article ID ATOMIC-ABSORPTION SPECTROMETRY; PLASMA-MASS-SPECTROMETRY; X-RAY-FLUORESCENCE; NEUTRON-ACTIVATION-ANALYSIS; RARE-EARTH ELEMENTS; PLATINUM-GROUP ELEMENTS; ROCK REFERENCE SAMPLES; COLUMN ION CHROMATOGRAPHY; ORIENTED GEOCHEMICAL LABORATORIES; CRETACEOUS TERTIARY BOUNDARY C1 US GEOL SURVEY,MENLO PK,CA 94025. US GEOL SURVEY,NATL CTR,RESTON,VA 22092. RP JACKSON, LL (reprint author), US GEOL SURVEY,DENVER FED CTR,POB 25046,MS 973,DENVER,CO 80225, USA. NR 426 TC 10 Z9 10 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JUN 15 PY 1991 VL 63 IS 12 BP R33 EP R48 PG 16 WC Chemistry, Analytical SC Chemistry GA FR519 UT WOS:A1991FR51900003 ER PT J AU IZETT, GA DALRYMPLE, GB SNEE, LW AF IZETT, GA DALRYMPLE, GB SNEE, LW TI AR-40/AR-39 AGE OF CRETACEOUS-TERTIARY BOUNDARY TEKTITES FROM HAITI SO SCIENCE LA English DT Article ID IMPACT; GEOCHRONOLOGY; CRATER AB Ar-40/Ar-39 dating of tektites discovered recently in Cretaceous-Tertiary (K-T) boundary marine sedimentary rocks on Haiti indicates that the K-T boundary and impact event are coeval at 64.5 +/- 0.1 million years ago. Sanidine from a bentonite that lies directly above the K-T boundary in continental, coal-bearing, sedimentary rocks of Montana was also dated and has a Ar-40/Ar-39 age of 64.6 +/- 0.2 million years ago, which is indistinguishable statistically from the age of the tektites. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP IZETT, GA (reprint author), US GEOL SURVEY,DENVER FED CTR,MAIL STOP 913,DENVER,CO 80225, USA. NR 49 TC 91 Z9 92 U1 0 U2 12 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD JUN 14 PY 1991 VL 252 IS 5012 BP 1539 EP 1542 DI 10.1126/science.252.5012.1539 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FR040 UT WOS:A1991FR04000043 PM 17834880 ER PT J AU BARKER, JS HARTZELL, SH BURDICK, LJ HELMBURGER, DV AF BARKER, JS HARTZELL, SH BURDICK, LJ HELMBURGER, DV TI ANALYSIS OF LOCAL SEISMIC WAVE-FORMS FROM UNDERGROUND NUCLEAR-EXPLOSIONS - FORWARD MODELING FOR EFFECTIVE SOURCE FUNCTIONS AT PAHUTE-MESA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID TEST SITE; TELESEISMIC OBSERVATIONS; NEAR-FIELD; ATTENUATION; DETONATIONS; WAVES AB In this study we use forward modeling of surface particle velocity data recorded within 15 km of underground nuclear explosions at Pahute Mesa in the Nevada Test Site. A plane-layered velocity structure model is developed, and effective source functions are obtained for six events with yields of 155-1300 kt (kilotons), recorded at ranges presumed to be well outside the zone of inelastic deformation. We then use the effective source functions determined from well outside the elastic radius to compute synthetic seismograms for comparison with recordings within the spall zone. Prior to the onset of spall the comparison is good, enabling us to estimate effective source functions for two additional events for which only recordings from the spall zone are available. As surface zero is approached, however, the first half cycle of the observed velocity records includes an inflection, which appears as a shoulder in acceleration records. This suggests that, in addition to the elastic arrival, we are seeing secondary arrivals due to spall opening or inelastic shock wave propagation. Elastic wave propagation predicts the observed peak velocities well beyond a scaled slant range of about 175 m/(kt)1/3 but overpredicts the first phase at closer ranges. This limit of applicability of elastic wave propagation provides a useful estimate of the elastic radius for Pahute Mesa explosions. Yield scaling relations are determined using three events of known yield, and these are then used to estimate yields for the eight Pahute Mesa explosions modeled in this study. Finally, implications for the attenuation of teleseismic body waves are discussed. C1 WOODWARD CLYDE CONSULTANTS, PASADENA, CA 91101 USA. US GEOL SURVEY, DENVER, CO 80225 USA. CALTECH, SEISMOL LAB, PASADENA, CA 91125 USA. RP SUNY, DEPT GEOL SCI & ENVIRONM STUDIES, BINGHAMTON, NY 13902 USA. NR 36 TC 2 Z9 2 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUN 10 PY 1991 VL 96 IS B6 BP 10129 EP 10143 DI 10.1029/91JB00476 PG 15 WC Geosciences, Multidisciplinary SC Geology GA FR246 UT WOS:A1991FR24600021 ER PT J AU CHOUET, B SHAW, HR AF CHOUET, B SHAW, HR TI FRACTAL PROPERTIES OF TREMOR AND GAS PISTON EVENTS OBSERVED AT KILAUEA VOLCANO, HAWAII SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID FLUID-DRIVEN CRACK; STRANGE ATTRACTORS; CHAOS; DIMENSIONS; MECHANISM; DYNAMICS; SPECTRUM; SYSTEMS; SETS AB We study the fractal properties of shallow volcanic tremor and gas piston events associated with magma degassing at Kilauea Volcano, Hawaii, using data from two dense short-baseline arrays of seismographs deployed near the active crater of Puu Oo on the east rift of the volcano. We found an upper bound on the fractal dimension of a strange attractor common to phase portraits of both tremor and gas piston activities in the range of 3.1-4.5 with a mean of 3.75 over a scale length of the wave field of the order of 100 m. The dimension of the attractor fluctuates over the course of tremor and gas piston episodes within a range comparable to the spatial variations of fractal dimensions found in the wave field. The existence of a categorically stable attractor characterizing both types of activities strongly suggests that the excitation mechanism of tremor is similar to that of gas piston events, which in turn are correlated with visual observations at the volcanic vent. The low value derived for the dimension of the attractor in phase space points to significant self-organization in the process of generation of tremor and offers general constraints on the dimensionality of attractors derived from models of acoustic emission associated with magma flow, vesiculation, and degassing. RP CHOUET, B (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 53 TC 42 Z9 42 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUN 10 PY 1991 VL 96 IS B6 BP 10177 EP 10189 DI 10.1029/91JB00772 PG 13 WC Geosciences, Multidisciplinary SC Geology GA FR246 UT WOS:A1991FR24600024 ER PT J AU SHAW, HR CHOUET, B AF SHAW, HR CHOUET, B TI FRACTAL HIERARCHIES OF MAGMA TRANSPORT IN HAWAII AND CRITICAL SELF-ORGANIZATION OF TREMOR SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID FLUID-DRIVEN CRACK; KILAUEA VOLCANO; MECHANISM; ASCENT; MOTION; MODEL AB A hierarchical model of magma transport in Hawaii is developed from the seismic records of deep (30-60 km) and intermediate-depth (5-15 km) harmonic tremor between January 1, 1962, and December 31, 1983. We find two kinds of spatial distributions of magma fractions at depths below 5 km, defined by the fractal dimension D3, where the subscript is the embedding dimension. The first is a focused distribution with D3 = 0.28, and the second is a disperse distribution with D3 = 1.52. The former dimension reflects conduitlike structures where the magma flow converges toward a summit magma chamber and the fractal dimension tends to zero. The latter dimension reflects multifractal clustering of dendritic fractures where hypocentral domains represent subsets of fractures within spherical domains with an average radius of about 1 km. These geometries constitute a percolation network of clustered intermittent fracture and magma transport. The magma volume of the average fracture is about 2 x 10(4) m3. A tremor model of magma transport is developed from mass balances of percolation that are proportional to tremor durations. It gives reasonable magma fractions and residence times for a vertical drift velocity of 4 km yr-1 and yields patterns of intermittency that are in accord with singularity analyses of the 22-year time series record. According to the model, sustained tremor is generated by the relaxation oscillations of the percolation network with a dominant frequency of about 1 Hz to obtain internally consistent values of fracture geometry, fracture opening force, and magma supply rate. Calculated tremor frequencies are higher in fracture networks of small volume in harmony with the observed relation between seismic amplitude and dominant frequency of tremor. Tectonic relaxation times of rock stresses versus magma pressures are in fair agreement with the average length of tremor episodes and average period of tremor intermittencies. These observations suggest that a high degree of self-organization is characteristic of the nonlinear dynamics of fracture percolation and coupled tremor processes. Logarithms of frequencies (in hertz) of high-amplitude tremor (1-s period), mean tremor duration (28-min period), and mean onset interval (14-day period) are 0, -3.2, and -6.1, implying broadband maxima in the frequency spectrum of transport at intervals of 10(3). The next longer period of this sequence, which corresponds to eruptions and shallow intrusions, is about 32 years (10(-9) Hz), comparable to the average eruption intermission of Mauna Loa during the last 150 years (about 20 years). This and other evidence suggest that spatiotemporal universality extends from small to large scales in Hawaiian and other magmatic systems. The apparent universal scaling of frequencies may be more than 15 decades in time (1 s to about 60 m.y.) and 10 decades in length (0.1 mm to 10(3) km). RP SHAW, HR (reprint author), US GEOL SURVEY, 345 MIDDLEFIELD RD, MS 977, MENLO PK, CA 94025 USA. NR 51 TC 29 Z9 29 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUN 10 PY 1991 VL 96 IS B6 BP 10191 EP 10207 DI 10.1029/91JB00771 PG 17 WC Geosciences, Multidisciplinary SC Geology GA FR246 UT WOS:A1991FR24600025 ER PT J AU QUILTY, EG ROELOFFS, EA AF QUILTY, EG ROELOFFS, EA TI REMOVAL OF BAROMETRIC-PRESSURE RESPONSE FROM WATER LEVEL DATA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID WELLS AB The removal from water level data fluctuations due to barometric forcing at subtidal frequencies is studied using transfer functions. In a poorly confined well-aquifer system these transfer functions are, in general, dependent upon air diffusivity through the unsaturated zone and diffusivity from the water table into the unsaturated zone. The stability in time of estimated transfer functions from selected water well sites near Parkfield, California, is examined, and an average transfer function is computed for each site that demonstrates reasonable stability over time. Two of these transfer functions that show marked frequency dependence in the subtidal frequency band are used to filter water level data in this frequency range. A comparison is made with residuals after subtracting the best fitting multiple of band-passed barometric pressure from the water level data, and transfer function filtering is shown to be superior. Comparing the estimated transfer functions with previously derived theoretical ones shows that in one case the well-aquifer system can be reasonably well modeled by assuming that the effects of air and water diffusivity are nonnegligible, while the remaining frequency-dependent transfer function can be better modeled by assuming minimal air diffusivity through the unsaturated zone. RP QUILTY, EG (reprint author), US GEOL SURVEY,OFF EARTHQUAKES VOLCANOES & ENGN,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 9 TC 29 Z9 33 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUN 10 PY 1991 VL 96 IS B6 BP 10209 EP 10218 DI 10.1029/91JB00429 PG 10 WC Geosciences, Multidisciplinary SC Geology GA FR246 UT WOS:A1991FR24600026 ER PT J AU BROCHER, TM NOKLEBERG, WJ CHRISTENSEN, NI LUTTER, WJ GEIST, EL FISHER, MA AF BROCHER, TM NOKLEBERG, WJ CHRISTENSEN, NI LUTTER, WJ GEIST, EL FISHER, MA TI SEISMIC-REFLECTION REFRACTION MAPPING OF FAULTING AND REGIONAL DIPS IN THE EASTERN ALASKA RANGE SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID SOUTHERN ALASKA; DENALI-FAULT; WRANGELLIA; TRANSECT; TERRANE; ORIGIN; SYSTEM; ROCKS; CRUST AB We present the results of a Trans-Alaska Crustal Transect (TACT) investigation of the upper 2-5 km of the eastern Alaska Range in the vicinity of the Denali fault based on seismic reflection/refraction data, laboratory measurements of rock velocities, and structural mapping. The Denali fault is a major dextral slip structure mappable for more than 2000 km separating the Wrangellia and adjacent terranes to the south from the Yukon-Tanana and adjacent terranes to the north. Geologic mapping suggests over 400 km of dextral slip has occurred on the fault, yet within the upper 1.5 km of the crust along the TACT corridor, basement rocks juxtaposed along the Denali fault reveal no significant seismic velocity differences, although the fault zone itself is associated with a minor lowering of velocity. The lack of seismic velocity contrast adjacent to the fault is in agreement with laboratory measurements of elastic wave velocities of samples from terranes bordering the fault. Laboratory measurements of elastic wave velocities of the metasedimentary mica-quartz schists comprising the Yukon-Tanana basement are highly anisotropic because of preferred orientation of mica and predict significant variations in velocity accompanying variations in foliation dip. Although other interpretations are possible, the northward shallowing of foliation dip of basement rocks in the Yukon-Tanana terrane combined with the strong anisotropy associated with these highly foliated rocks can explain an observed northward increase in seismic velocity within this terrane. Seismic reflections from basement rocks within the Yukon-Tanana terrane may originate from variations in anisotropy with depth and/or changes in composition reflecting different proportions of sandstone and shale in the protolith. C1 PURDUE UNIV,DEPT EARTH & ATMOSPHER SCI,W LAFAYETTE,IN 47907. RP BROCHER, TM (reprint author), US GEOL SURVEY,MS 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 30 TC 12 Z9 12 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD JUN 10 PY 1991 VL 96 IS B6 BP 10233 EP 10249 DI 10.1029/91JB00905 PG 17 WC Geosciences, Multidisciplinary SC Geology GA FR246 UT WOS:A1991FR24600028 ER PT J AU SCHUENEMEYER, JH DREW, LJ AF SCHUENEMEYER, JH DREW, LJ TI A FORECAST OF UNDISCOVERED OIL AND GAS IN THE FRIO STRAND PLAIN TREND - THE UNFOLDING OF A VERY LARGE EXPLORATION PLAY SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Article AB In this study, we examined the rate at which oil and gas fields were discovered in the Frio strand plain exploration play, which is located in the central coastal plain of Texas, and estimated the size distribution of the oil and gas fields remaining to be discovered. The analysis of past rates of discovery in this play provides insight into the advanced stages of an exploration play in which many very small fields have been discovered. This observation was made during examination of changes in the distribution of field sizes as the play was driven toward total physical exhaustion by the increased petroleum demand due to the massive rise in oil and gas prices in the late 1970s and early 1980s. During this period, exploratory drilling was directed at a suite of prospects that contained very small oil and gas fields (almost all having less than 1 million bbl of recoverable oil equivalent). Analysis of this data suggests that the size distribution of fields is log geometric in form. On the basis of data obtained through February 1982, when 5000 wildcat wells had been drilled in the play, we predicted that 1163.2 fields remained to be discovered. Each field was estimated to contain more than 95,000 bbl of recoverable oil. The total volume of oil equivalent remaining to be discovered was predicted to be 726.8 million bbl, 51.5% of which is in fields smaller than 1.52 million bbl in size. C1 US GEOL SURVEY,RESTON,VA 22092. RP SCHUENEMEYER, JH (reprint author), UNIV DELAWARE,DEPT MATH SCI,501 EWING HALL,NEWARK,DE 19716, USA. NR 14 TC 2 Z9 3 U1 0 U2 2 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1107 EP 1115 PG 9 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800006 ER PT J AU BARKER, CE JOHNSON, RC PAWLEWICZ, MJ CRYSDALE, BL CLARK, AC AF BARKER, CE JOHNSON, RC PAWLEWICZ, MJ CRYSDALE, BL CLARK, AC TI COAL-BED METHANE SHOW WITHIN THE WIND RIVER INDIAN RESERVATION ENHANCES GAS PROSPECTS IN DEEPER PORTIONS OF THE WIND RIVER BASIN, WYOMING SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1122 EP 1122 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800012 ER PT J AU BARKER, CE PETERSON, JA POOLE, FG AF BARKER, CE PETERSON, JA POOLE, FG TI THERMAL MATURITY TRENDS FROM ROCK-EVAL AND VITRINITE REFLECTANCE ANALYSIS ON POTENTIAL SOURCE ROCKS IN EASTERN NEVADA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1123 EP 1123 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800013 ER PT J AU DYMAN, TS ANDERSON, SB CAMPEN, EB COBBAN, WA FOX, JE HAMMOND, RH PORTER, KW RICE, DD SETTERHOLM, DR SHURR, GU AF DYMAN, TS ANDERSON, SB CAMPEN, EB COBBAN, WA FOX, JE HAMMOND, RH PORTER, KW RICE, DD SETTERHOLM, DR SHURR, GU TI WEST-EAST STRATIGRAPHIC TRANSECT OF CRETACEOUS ROCKS - SOUTHWESTERN MONTANA TO WESTERN MINNESOTA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. N DAKOTA GEOL SURVEY,BISMARCK,ND. S DAKOTA SCH MINES,RAPID CITY,SD. S DAKOTA GEOL SURVEY,VERMILLION,SD. MINNESOTA GEOL SURVEY,ST PAUL,MN. ST CLOUD STATE UNIV,ST CLOUD,MN. NR 0 TC 0 Z9 0 U1 2 U2 2 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1125 EP 1125 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800023 ER PT J AU FLORES, RM KEIGHIN, CW KEEFER, WR AF FLORES, RM KEIGHIN, CW KEEFER, WR TI BASIN-WIDE ARCHITECTURE OF SANDSTONE RESERVOIRS IN THE FORT UNION FORMATION, WIND RIVER BASIN, WYOMING SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1126 EP 1126 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800028 ER PT J AU HESTER, TC SCHMOKER, JW AF HESTER, TC SCHMOKER, JW TI REGIONAL GEOLOGIC CHARACTERISTICS RELEVANT TO HORIZONTAL DRILLING, WOODFORD SHALE, ANADARKO BASIN, OKLAHOMA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1128 EP 1128 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800035 ER PT J AU HIGLEY, DK TAKAHASHI, KI DYMAN, TS AF HIGLEY, DK TAKAHASHI, KI DYMAN, TS TI INTERACTIVE COMPUTER DISPLAY OF PETROLEUM-EXPLORATION HISTORY FOR BASINS IN THE NORTHERN ROCKY-MOUNTAIN REGION OF THE UNITED-STATES SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1128 EP 1128 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800036 ER PT J AU LAW, BE AF LAW, BE TI THE RELATIONSHIP BETWEEN COAL RANK AND CLEAR DENSITY - A PRELIMINARY-REPORT SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1131 EP 1131 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800047 ER PT J AU LUND, K BEARD, LS PERRY, WJ AF LUND, K BEARD, LS PERRY, WJ TI EXTENSIONAL GEOMETRIES IN THE NORTHERN GRANT RANGE, EAST-CENTRAL NEVADA - IMPLICATIONS FOR OIL OCCURRENCES IN RAILROAD VALLEY SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. US GEOL SURVEY,FLAGSTAFF,AZ 86001. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1131 EP 1132 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800050 ER PT J AU MULLARKEY, JC CLAYTON, JL WENDLANDT, RF DAWS, TA AF MULLARKEY, JC CLAYTON, JL WENDLANDT, RF DAWS, TA TI PETROLEUM SOURCE ROCK EVALUATION OF THE CRETACEOUS NEWARK CANYON FORMATION IN NORTH-CENTRAL NEVADA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 COLORADO SCH MINES,GOLDEN,CO 80401. US GEOL SURVEY,DENVER,CO 80225. COLORADO SCH MINES,GOLDEN,CO 80401. NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1134 EP 1134 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800061 ER PT J AU NUCCIO, VF SCHMOKER, JW FOUCH, TD AF NUCCIO, VF SCHMOKER, JW FOUCH, TD TI THERMAL MATURITY, POROSITY, AND FACIES RELATIONSHIPS APPLIED TO GAS GENERATION AND PRODUCTION IN TERTIARY AND CRETACEOUS LOW-PERMEABILITY SANDSTONES, UINTA BASIN, UTAH SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1134 EP 1135 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800063 ER PT J AU PAWLEWICZ, MJ NUCCIO, VF AF PAWLEWICZ, MJ NUCCIO, VF TI VITRINITE REFLECTANCE STUDY OF THE UPPER CRETACEOUS FRUITLAND FORMATION, SAN-JUAN BASIN, NEW-MEXICO SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1136 EP 1136 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800068 ER PT J AU PERRY, WJ BARKER, CE LUND, K AF PERRY, WJ BARKER, CE LUND, K TI A NEW OIL-GENERATION MODEL FOR PINE AND RAILROAD VALLEYS, NEVADA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1136 EP 1136 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800069 ER PT J AU POLLASTRO, RM SCHENK, CJ AF POLLASTRO, RM SCHENK, CJ TI ORIGIN AND DIAGENESIS OF CLAY-MINERALS IN RELATION TO SANDSTONE PARAGENESIS - AN EXAMPLE IN EOLIAN DUNE RESERVOIRS AND ASSOCIATED ROCKS, PERMIAN UPPER PART OF THE MINNELUSA FORMATION, POWDER RIVER BASIN, WYOMING SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 1 Z9 1 U1 1 U2 1 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1136 EP 1137 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800071 ER PT J AU POTTER, CJ GROW, JA LUND, K PERRY, WJ MILLER, JJ LEE, MW AF POTTER, CJ GROW, JA LUND, K PERRY, WJ MILLER, JJ LEE, MW TI REGIONAL SEISMIC-REFLECTION PROFILE FROM RAILROAD VALLEY TO LAKE VALLEY, EAST-CENTRAL NEVADA, REVEALS A VARIETY OF STRUCTURAL STYLES BENEATH NEOGENE BASINS SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1137 EP 1137 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800072 ER PT J AU PRICE, L LEFEVER, J AF PRICE, L LEFEVER, J TI HORIZONTAL DRILLING IN THE BAKKEN FORMATION - THE HUNT FOR AN ELEPHANT THAT NEVER LEFT THE SOURCE SYSTEM SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. N DAKOTA GEOL SURVEY,GRAND FORKS,ND. NR 0 TC 0 Z9 0 U1 1 U2 6 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1137 EP 1137 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800073 ER PT J AU RICE, DD AF RICE, DD TI GEOLOGIC SETTINGS AND CONTROLS OF SHALLOW GAS, ROCKY-MOUNTAIN AREA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1138 EP 1138 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800075 ER PT J AU SCHENK, CJ PETERSON, F AF SCHENK, CJ PETERSON, F TI EOLIAN SABKHA SANDSTONES IN THE NUGGET SANDSTONE (JURASSIC), VERNAL AREA, UTAH SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1139 EP 1139 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800080 ER PT J AU WEAVER, JN GRUBER, JR AF WEAVER, JN GRUBER, JR TI TERTIARY FLUVIAL SYSTEMS WITHIN THE BEAR CREEK COAL FIELD, NORTHERN BIG HORN BASIN, MONTANA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. BUR LAND MANAGEMENT,BILLINGS,MT. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD JUN PY 1991 VL 75 IS 6 BP 1143 EP 1143 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FQ258 UT WOS:A1991FQ25800098 ER PT J AU RUMSEY, GL KINSELLA, JE SHETTY, KJ HUGHES, SG AF RUMSEY, GL KINSELLA, JE SHETTY, KJ HUGHES, SG TI EFFECT OF HIGH DIETARY CONCENTRATIONS OF BREWERS DRIED YEAST ON GROWTH-PERFORMANCE AND LIVER URICASE IN RAINBOW-TROUT (ONCORHYNCHUS-MYKISS) SO ANIMAL FEED SCIENCE AND TECHNOLOGY LA English DT Article ID AMINO-ACID SUPPLEMENTATION; FINGERLINGS; RICHARDSON; NITROGEN; PURINES; PROTEIN; FOOD AB The potential of using yeast nitrogen in fish feeds to replace proteins from conventional sources is an attractive option to nutritionists, feed manufacturers and fish farmers. Experiments were conducted to determine the effects of high dietary levels of brewer's dried yeast, with 20% of its protein represented by nucleic acid nitrogen, on the growth, feed conversion efficiency and uric acid metabolism of rainbow trout (Oncorhynchus mykiss). Growth and liver uricase activities were monitored in trout fed diets containing 0, 25, 50 or 75% yeast. Growth was faster and feed conversion more efficient in fish fed diets consisting of 25% yeast; the diets containing 50 and 75% yeast were seemingly unpalatable to trout. Liver uricase activity, present in all fish, was directly correlated with the dietary level of nucleic acids. It was concluded that although feed intake was depressed at yeast levels greater than 25%, the fish did not appear to be adversely affected physiologically by high dietary levels of nucleic acid nitrogen. C1 CORNELL UNIV, INST FOOD SCI, ITHACA, NY 14853 USA. RP US FISH & WILDLIFE SERV, TUNISON LAB FISH NUTR, 3075 GRACIE RD, CORTLAND, NY 13045 USA. NR 20 TC 53 Z9 55 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-8401 EI 1873-2216 J9 ANIM FEED SCI TECH JI Anim. Feed Sci. Technol. PD JUN PY 1991 VL 33 IS 3-4 BP 177 EP 183 DI 10.1016/0377-8401(91)90058-Z PG 7 WC Agriculture, Dairy & Animal Science SC Agriculture GA FV138 UT WOS:A1991FV13800001 ER PT J AU RUMSEY, GL HUGHES, SG SMITH, RR KINSELLA, JE SHETTY, KJ AF RUMSEY, GL HUGHES, SG SMITH, RR KINSELLA, JE SHETTY, KJ TI DIGESTIBILITY AND ENERGY VALUES OF INTACT, DISRUPTED AND EXTRACTS FROM BREWERS DRIED YEAST FED TO RAINBOW-TROUT (ONCORHYNCHUS-MYKISS) SO ANIMAL FEED SCIENCE AND TECHNOLOGY LA English DT Article ID NUCLEIC-ACID; PROTEIN; RICHARDSON AB Although fish meal has historically been used as the primary source of protein in fish feeds, brewer's dried yeast (BDY) is presently being investigated as a primary replacement for fish meal. As little is known about the ability of fish to utilize BDY, studies were conducted to study bioavailability of intact BDY as well as several fractions derived from the disrupted yeast to rainbow trout. Dried BDY was fed to rainbow trout and digestibility and energy values were determined. When the yeast cells were fully disrupted, the absorption of nitrogen increased by more than 20% and the metabolizable energy of the yeast by more than 10%. Energy and nitrogen digestibility were further increased after the removal of all wall material and separation of nitrogen into amino acid and nucleic acid fractions. Disruption of the cell wall significantly increased the nutritional value of BDY for salmonid fishes. The findings suggest that further research be conducted on the use and economy of BDY as a primary nitrogen source in fish feeds. C1 CORNELL UNIV,INST FOOD SCI,ITHACA,NY 14853. RP RUMSEY, GL (reprint author), US FISH & WILDLIFE SERV,TUNISON LAB FISH NUTR,CORTLAND,NY 13045, USA. NR 30 TC 45 Z9 48 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-8401 J9 ANIM FEED SCI TECH JI Anim. Feed Sci. Technol. PD JUN PY 1991 VL 33 IS 3-4 BP 185 EP 193 DI 10.1016/0377-8401(91)90059-2 PG 9 WC Agriculture, Dairy & Animal Science SC Agriculture GA FV138 UT WOS:A1991FV13800002 ER PT J AU TAYLOR, HE GARBARINO, JR KOIRTYOHANN, SR AF TAYLOR, HE GARBARINO, JR KOIRTYOHANN, SR TI FLAME IONIZATION MASS-SPECTROMETRY - ISOTOPE RATIO DETERMINATIONS FOR POTASSIUM SO APPLIED SPECTROSCOPY LA English DT Article DE FLAME SPECTROSCOPY; MASS SPECTROSCOPY ID INDUCTIVELY COUPLED PLASMA AB The air/acetylene flame provides a convenient ion source for the determination of potassium isotopic ratios by mass spectrometry. Unlike the argon inductively coupled plasma (ICP), the flame provides low background in the mass region of interest. Ion production is quite satisfactory for isotope ratio measurements at the micrograms per milliliter (mu-g/mL) level and slightly below, with 1-mu-g/mL potassium giving about 10(5) counts/second at a nominal mass-to-charge ratio of 39. The detection limit for potassium was 2-3 nanograms per milliliter (ng/mL). The ratio of K-41/K-39 was measured with 0.5-1% relative standard deviation, and a K-41 spike representing 0.2% of the total potassium was readily detected. Both signal levels and signal stability were improved by adding a second easily ionized element such as cesium to samples and standards. Alternatively, a cesium solution could be aspirated for about 1 minute between sample measurements to ensure signal stability. C1 UNIV MISSOURI,DEPT CHEM,COLUMBIA,MO 65211. RP TAYLOR, HE (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,DENVER,CO 80225, USA. NR 6 TC 9 Z9 9 U1 0 U2 1 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD JUN PY 1991 VL 45 IS 5 BP 886 EP 889 DI 10.1366/0003702914336444 PG 4 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA FV083 UT WOS:A1991FV08300025 ER PT J AU RUMSEY, GL AF RUMSEY, GL TI CHOLINE BETAINE REQUIREMENTS OF RAINBOW-TROUT (ONCORHYNCHUS-MYKISS) SO AQUACULTURE LA English DT Article ID METHIONINE AB A series of experiments with rainbow trout (Oncorhynchus mykiss) were conducted to quantify the dietary requirement for choline as well as to determine whether betaine or methionine could spare the trout's choline requirement. Fish weighing 1.4 and 3.2 g, which were acclimated to a choline-deficient semipurified diet for 14 days before the start of the experiments, were shown to have a choline requirement of 813 and 714 ppm, respectively. When an excess of betaine was added to the choline-deficient basal diet, the choline requirement was reduced to about 400 ppm. These results suggest that about half of the trout's choline requirement must be met by choline itself, whereas the other half can be supplied by betaine. However, the requirement for choline itself must first be met before a response to betaine can be obtained. The addition of betaine to a choline-deficient diet resulted in no improvement in weight gain. Likewise, the addition of L-methionine, isomethyl to 1000 ppm choline, was without effect on growth in a basal diet marginally adequate in sulfur amino acids - suggesting that the trout's requirement for choline is not replaceable by methionine. Because the effects of dietary choline on liver lipid were variable and difficult to interpret, it was demonstrated that growth was more sensitive than liver lipid as an indicator of choline status. RP RUMSEY, GL (reprint author), US FISH & WILDLIFE SERV,TUNISON LAB FISH NUTR,CORTLAND,NY 13045, USA. NR 26 TC 40 Z9 46 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD JUN 1 PY 1991 VL 95 IS 1-2 BP 107 EP 116 DI 10.1016/0044-8486(91)90077-K PG 10 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA FT848 UT WOS:A1991FT84800011 ER PT J AU XIE, JK LIU, ZY HERRMANN, RB CRANSWICK, E AF XIE, JK LIU, ZY HERRMANN, RB CRANSWICK, E TI SOURCE PROCESSES OF 3 AFTERSHOCKS OF THE 1983 GOODNOW, NEW-YORK, EARTHQUAKE - HIGH-RESOLUTION IMAGES OF SMALL, SYMMETRICAL RUPTURES SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID EMPIRICAL GREEN-FUNCTIONS; HARD-ROCK SITES; SOURCE PARAMETERS; SPECTRAL-ANALYSIS; GROUND MOTION; CALIFORNIA; FREQUENCY; PREDICTION; EASTERN; STRESS AB Broadband, large dynamic range GEOS data from four aftershocks (ML approximately 2 to 3) of the 1983 Goodnow, New York, earthquake, recorded at hard-rock sites 2 to 7 km away from the epicentral area, are used to study rupture processes of three larger events, with an M(L) = 1.6 event as the Green's function event. We analyze the spectra and spectral ratios of ground velocity at frequencies up to 100 Hz, and conclude that (1) there are resolvable P-wave f(max) (51 and 57 Hz) at two sites; (2) there is abundant information on sources of larger events up to frequencies of 50 to 60 Hz; and (3) there is an unstable, nonlinear instrument resonance at about 90 Hz. We analyze the artifacts of low-pass filters in the deconvolved rupture process, including the limited time resolution and biases in the rise-time measurement. Some extensions of the empirical Green's function (EGF) method are proposed to reduce these artifacts and to precisely estimate the relative locations of events that are close both in time and in space. Applying the EGF method to three aftershocks, we find that these events have ruptures that are simple crack-like, characterized by small fault radii (approximately 70 to 120 m) and static stress drops that vary, depending on the size of the events, between about 5 to 16 bars. We also find that two of the events, with origin times differing by 0.60 sec, are separated by 190 +/- 110 meters. Assuming a causal relationship between the two would result in a slow propagation velocity (0.05 +/- 0.03 time of the local shear-wave velocity). We therefore interpret the corresponding ruptures as being distinct, the area between the rupturing patches having a characteristic length much smaller than those of the rupturing patches. Comparison of the results of this study with those obtained for the Goodnow main shock and microearthquakes in California and Hawaii suggests that the stress drops of the Goodnow aftershocks decrease considerably (by up to a factor of 25 or more) from those estimated for the main shock, even after the estimated large uncertainty in the latter estimates is considered. This decrease is similar to those reported for the Nahanni earthquakes (m(b) = 5.0 to 6.5) in Northwest Territories and for the North Palm Springs earthquake (M(L) = 5.9) sequence in California. The stress drops of the simple, crack like microearthquakes are significantly variable (by factors between 3 and 27) within the single source areas. The median of stress drops of the intraplate Goodnow aftershocks is lower (by factors of 2 to 4) than the medians calculated for the other, interplate microearthquake sequences. C1 ST LOUIS UNIV,DEPT EARTH & ATMOSPHERE SCI,ST LOUIS,MO 63103. US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. NR 38 TC 24 Z9 25 U1 0 U2 2 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD JUN PY 1991 VL 81 IS 3 BP 818 EP 843 PG 26 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FR329 UT WOS:A1991FR32900007 ER PT J AU SAVAGE, JC AF SAVAGE, JC TI CRITICISM OF SOME FORECASTS OF THE NATIONAL EARTHQUAKE PREDICTION EVALUATION COUNCIL SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID SAN-ANDREAS; CALIFORNIA AB The Working Group on California Earthquake Probabilities has assigned probabilities for rupture in the interval from 1988 to 2018 to various segments of the San Andreas fault on the basis of the lognormal distribution of recurrence times of characteristic earthquakes postulated by Nishenko and Buland (1987). I question the validity of those probabilities on the basis of three separate arguments: (1) The distributions of recurrence times of the four, best-observed, characteristic-earthquake sequences are each only marginally consistent with the Nishenko-Buland lognormal distribution. (2) The range of possible 30-year conditional probabilities for many of the fault segments is so great due to uncertainty in the average recurrence time for that segment that the assigned probability is virtually meaningless. (3) The 1988 forecasts not subject to the foregoing objection are those in which there is a low probability of an earthquake in the near future (e.g., only a 5 per cent chance of rupture of the North Coast segment before the year 2049 and of the Carrizo segment before the year 2018). The same reasoning would assign only a 5 per cent chance of rupture before mid-1993 to the southern Santa Cruz Mountains segment, the segment that failed in October 1989. Finally, the forecast of the next Parkfield earthquake (95 per cent probability before 1993.0) by Bakun and Lindh (1985) depends upon an ad hoc explanation of the out-of-sequence 1934 earthquake. A less-contrived forecast would have assigned a conditional probability of about 60 +/- 20 per cent to the 1985.0 to 1993.0 interval and 30 +/- 15 per cent to the 1990.0 to 1993.0 interval. RP SAVAGE, JC (reprint author), US GEOL SURVEY,MS-977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 14 TC 53 Z9 53 U1 0 U2 1 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD JUN PY 1991 VL 81 IS 3 BP 862 EP 881 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FR329 UT WOS:A1991FR32900009 ER PT J AU MCGARR, A AF MCGARR, A TI ON A POSSIBLE CONNECTION BETWEEN 3 MAJOR EARTHQUAKES IN CALIFORNIA AND OIL PRODUCTION SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID WHITTIER-NARROWS EARTHQUAKE; FLUID EXTRACTION; LOS-ANGELES; FAULT; DEFORMATION; STRESS; RANGES AB The 1983 Coalinga M 6.5, the 1985 Kettleman North Dome M 6.1, and the 1987 Whittier Narrows M 5.9 earthquake sequences each occurred beneath major producing oil fields and caused an aftershock sequence whose epicentral extent coincides approximately with that of the overlying oil field. Despite this coincidence, a causal relationship between these sequences and oil production has been discounted because the earthquakes were located at depths of the order of 10 km, whereas oil production is confined to the topmost several km. Moreover, because all three oil fields, Coalinga, Kettleman, North Dome, and Montebello, are situated on anticlines that have undergone recent uplift as a consequence of horizontal tectonic compression of the crust, natural earthquakes are not unexpected. A mechanical connection between oil production and the earthquake sequence is suggested, however, by the observation that in each case the total seismic deformation was just that required to offset the force imbalance caused by oil production. Specifically, for each of the three sequences SIGMA-M0 = 2-mu-DELTA-m-gamma/rho-c, where SIGMA-M0 is the sum of the seismic moments, mu is the modulus of rigidity, Am is the mass of the fluid removed due to oil production, gamma is the fraction of the upper crust that is seismogenic, and rho-c, is the average upper crustal density. In essence, net extraction of oil and water reduces slightly the average density of the upper crust, causing an isostatic imbalance. The ductile lower crust deforms in response to this imbalance, thus increasing the load on the seismogenic layer, which fails seismically to thicken the crust so as to restore static equilibrium locally. Accordingly, earthquakes near the base of the upper crust may be an expected outcome of major oil production from growing anticlines, irrespective of the depths of the producing formations. RP US GEOL SURVEY, 345 MIDDLEFIELD RD, MS 977, MENLO PK, CA 94025 USA. NR 58 TC 32 Z9 32 U1 0 U2 7 PU SEISMOLOGICAL SOC AMER PI ALBANY PA 400 EVELYN AVE, SUITE 201, ALBANY, CA 94706-1375 USA SN 0037-1106 EI 1943-3573 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD JUN PY 1991 VL 81 IS 3 BP 948 EP 970 PG 23 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FR329 UT WOS:A1991FR32900013 ER PT J AU HINKLEY, TK AF HINKLEY, TK TI DISTRIBUTION OF METALS BETWEEN PARTICULATE AND GASEOUS FORMS IN A VOLCANIC PLUME SO BULLETIN OF VOLCANOLOGY LA English DT Article AB In order to gain information on the distribution of metals between particles and gaseous forms in the plume of Kilauea volcano, a filter designed to collect metals associated with particles was followed in series by two other collectors intended to trap metals present in gaseous (atomic, molecular, or complexed) form: first an acid-bubbler bath and then a cold trap. Of the six metals measured, all of the In, Tl and Bi, and almost all of the Cd, Pb and Cu were found on the filter. None of any of the metals was detected in the acid-bubbler bath. Masses equivalent to 0.3% of the amount of Cd on the filter, 0.4% of the amount of Pb, and 9.3% of the Cu, were measured in the cold trap. The results indicate that all or nearly all of the six metals were partitioned to the particulate portion of the physical mixture of gases and particles that constitutes a volcanic plume, but that there may be systematic differences between chalcophile metals in the ways they are partitioned between particulate and gaseous phases in a cooled plume, and possibly differences in the acidity or other chemical properties of the molecular phases. RP HINKLEY, TK (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,DENVER,CO 80225, USA. NR 0 TC 33 Z9 33 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0258-8900 J9 B VOLCANOL JI Bull. Volcanol. PD JUN PY 1991 VL 53 IS 5 BP 395 EP 400 DI 10.1007/BF00280229 PG 6 WC Geosciences, Multidisciplinary SC Geology GA FU976 UT WOS:A1991FU97600005 ER PT J AU MANNY, BA EDSALL, TA WUJEK, DE AF MANNY, BA EDSALL, TA WUJEK, DE TI COMPSOPOGON CF COERULEUS, A BENTHIC RED ALGA (RHODOPHYTA) NEW TO THE LAURENTIAN GREAT-LAKES SO CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE LA English DT Article DE BENTHIC; COMPSOPOGON; FRESH-WATER RED ALGAE; GREAT LAKES; LAKE HURON ID NORTH CHANNEL; GEORGIAN BAY; WATER; HURON AB We found Compsopogon cf. coeruleus for the first time in the Laurentian Great Lakes, growing on limestone rocks at a depth of 21 m on Six Fathom Bank in central Lake Huron. It is the first freshwater red alga to be found in the Great Lakes and the only red alga ever found on an offshore reef in the Great Lakes. However, because this alga usually inhabits water 10-28-degrees-C and has not survived freezing winter temperatures elsewhere, it may not be a permanent member of the flora. C1 CENT MICHIGAN UNIV,DEPT BIOL,MT PLEASANT,MI 48859. RP MANNY, BA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,1451 GREEN RD,ANN ARBOR,MI 48105, USA. NR 31 TC 7 Z9 8 U1 0 U2 2 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4026 J9 CAN J BOT JI Can. J. Bot.-Rev. Can. Bot. PD JUN PY 1991 VL 69 IS 6 BP 1237 EP 1240 PG 4 WC Plant Sciences SC Plant Sciences GA GB330 UT WOS:A1991GB33000011 ER PT J AU BACKMAN, TWH AF BACKMAN, TWH TI GENOTYPIC AND PHENOTYPIC VARIABILITY OF ZOSTERA-MARINA ON THE WEST-COAST OF NORTH-AMERICA SO CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE LA English DT Article DE SEAGRASSES; COMMON-GARDEN EXPERIMENT; ECOTYPES; MORPHOMETRICS; GENOTYPES ID EELGRASS; SEAGRASSES; PHENOLOGY; GRADIENTS AB The relation between environmental factors and leaf morphology of Zostera marina L. have long been unclear, primarily because the species is intrinsically variable. The common-garden method was used to determine the genetic, environmental, and interaction components of leaf size variation. Zostera marina consists of several ecotypes with a wide range of phenotypic plasticity. Variation in the morphology of Z. marina was of three types: genetic, accounting for 14% across the localities studied; environmental (phenotypic plasticity along temporal and spatial gradients), accounting for 32%; and interaction between genotype and environmental, accounting for 35%. Five ecotypes were described for the North American Pacific coast: Z. marina L. var. izembekensis Backman, Z. marina L. var. typica Setchell, Z. marina L. var. phillipsii Backman, Z. marina L. var. latifolia Morong, Z. marina L. var. atam Backman. Temporal variation was due to seasonal phenotypic changes in ecotypes. Zostera marina var. izembekensis showed little seasonal morphological changes; Z. marina var. typica demonstrated minor increase in leaf size in spring and summer. Zostera marina var. phillipsii and Z. marina var. latifolia behaved similarly in that leaf size of both increased markedly in spring through early summer. Zostera marina var. phillipsii is adapted to Hood Canal and Puget Sound while Z. marina var. latifolia occupies the outer coast. Zostera marina var. atam exhibits sexual reproduction exclusively and is specifically adapted to the Gulf of California. C1 US FISH & WILDLIFE SERV,NATL FISHERY RES & DEV LAB,WELLSBORO,PA 16901. NR 60 TC 30 Z9 30 U1 9 U2 28 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4026 J9 CAN J BOT JI Can. J. Bot.-Rev. Can. Bot. PD JUN PY 1991 VL 69 IS 6 BP 1361 EP 1371 PG 11 WC Plant Sciences SC Plant Sciences GA GB330 UT WOS:A1991GB33000028 ER PT J AU BREW, DA KARL, SM BARNES, DF JACHENS, RC FORD, AB HORNER, R AF BREW, DA KARL, SM BARNES, DF JACHENS, RC FORD, AB HORNER, R TI A NORTHERN CORDILLERAN OCEAN CONTINENT TRANSECT - SITKA SOUND, ALASKA, TO ATLIN LAKE, BRITISH-COLUMBIA SO CANADIAN JOURNAL OF EARTH SCIENCES LA English DT Article ID SOUTHEASTERN ALASKA; WRANGELLIA; MOUNTAINS; CANADA AB The 155 km wide, 310 km long Sitka Sound - Atlin Lake continent-ocean transect includes almost all the geologic, geophysical, and geotectonic elements of the Canadian Cordillera. It crosses the Chugach, Wrangellia, Alexander, Stikine, and Cache Creek terranes, the Gravina and Laberge overlap assemblages, intrusive and metamorphic belts, and neotectonic faults that bound major blocks. Linear belts of magnetic highs are associated with Jurassic and Cretaceous granitic belts in Wrangellia and the western and central parts of the Alexander terrane and with the granitic rocks of the Coast plutonic-metamorphic complex (CPMC). The Border Ranges fault may be expressed at depth on either side of the Peril Strait fault. An enigmatic northeast-trending gradient in the CPMC and adjacent rocks separates a regional magnetic low to the northwest from a 300 nT high field to the southeast. The Bouguer gravity field decreases in broad steps from Pacific crust high values to lows at the international boundary, with pronounced gradients at the east edge of Chugach terrane and west edge of of CPMC. It indicates that the crust thickens from about 20 to 40 km from southwest to northeast. Ultramafic bodies in the Chugach, Alexander, and Wrangellia terranes and Gravina assemblage underlie local highs. Most of the accumulated seismic strain is released by large earthquakes on the Fairweather-Queen Charlotte Islands plate-margin fault, but the northern part of the Glacier Bay region, the Denali fault zone, and the Coast Mountains also have significant seismicity. Part of the Glacier Bay region is being uplifted at a high rate. Most of these features are related to the joining of (i) Wrangellia to Alexander terrane (Carboniferous), (ii) Stikine to Cache Creek terrane (Early Jurassic), (iii) Alexander terrane and Gravina assemblage to Stikine (Late Cretaceous), and (iv) Chugach to Wrangellia and Alexander terrane (Late Cretaceous or Paleogene). C1 US GEOL SURVEY, ANCHORAGE, AK 99508 USA. GEOL SURVEY CANADA, PACIFIC GEOSCI CTR, SIDNEY V8L 4B2, BC, CANADA. RP BREW, DA (reprint author), US GEOL SURVEY, MS 904, MENLO PK, CA 94025 USA. NR 31 TC 10 Z9 10 U1 0 U2 5 PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS PI OTTAWA PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA SN 0008-4077 EI 1480-3313 J9 CAN J EARTH SCI JI Can. J. Earth Sci. PD JUN PY 1991 VL 28 IS 6 BP 840 EP 853 DI 10.1139/e91-077 PG 14 WC Geosciences, Multidisciplinary SC Geology GA GD679 UT WOS:A1991GD67900002 ER PT J AU GEHRELS, GE MCCLELLAND, WC SAMSON, SD PATCHETT, PJ BREW, DA AF GEHRELS, GE MCCLELLAND, WC SAMSON, SD PATCHETT, PJ BREW, DA TI U-PB GEOCHRONOLOGY OF LATE CRETACEOUS AND EARLY TERTIARY PLUTONS IN THE NORTHERN COAST MOUNTAINS BATHOLITH SO CANADIAN JOURNAL OF EARTH SCIENCES LA English DT Article ID BRITISH-COLUMBIA; SOUTHEAST ALASKA; HOLKHAM-BAY; COMPLEX; ROCKS; EVOLUTION AB U-Pb geochronologic studies demonstrate that steeply dipping, sheetlike tonalitic plutons along the western margin of the northern Coast Mountains batholith were emplaced between approximately 83 and approximately 57 (perhaps approximately 55) Ma. Less elongate tonalitic-granodioritic bodies in central portions of the batholith yield ages of 59-58 Ma, coeval with younger phases of the tonalitic sheets. Large granite-granodiorite bodies in central and eastern portions of the batholith were emplaced at 51-48 Ma. Trends in ages suggest that the tonalitic bodies generally become younger southeastward and that, at the latitude of Juneau, plutonism migrated northeastward across the batholith at approximately 0.9 km/Ma. Variations in the age, shape, location, and degree of fabric development among the various plutons indicate that Late Cretaceous - Paleocene tonalitic bodies were emplaced into a steeply dipping, dip-slip shear zone that was active along the western margin of the batholith. Postkinematic Eocene plutons were emplaced at shallow crustal levels. Inherited zircon components in these plutons range in age from mid-Paleozoic to Early Proterozoic and are coeval with detrital zircons in adjacent metasedimentary rocks. These old zircons, combined with evolved Nd isotopic signatures for most plutons, record assimilation of continental crustal or supracrustal rocks during the generation and (or) ascent of the plutons. C1 US GEOL SURVEY, MENLO PK, CA 94025 USA. RP GEHRELS, GE (reprint author), UNIV ARIZONA, DEPT GEOSCI, TUCSON, AZ 85721 USA. NR 52 TC 48 Z9 48 U1 0 U2 3 PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS PI OTTAWA PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA SN 0008-4077 EI 1480-3313 J9 CAN J EARTH SCI JI Can. J. Earth Sci. PD JUN PY 1991 VL 28 IS 6 BP 899 EP 911 DI 10.1139/e91-082 PG 13 WC Geosciences, Multidisciplinary SC Geology GA GD679 UT WOS:A1991GD67900007 ER PT J AU DISTEFANO, RJ NEVES, RJ HELFRICH, LA LEWIS, MC AF DISTEFANO, RJ NEVES, RJ HELFRICH, LA LEWIS, MC TI RESPONSE OF THE CRAYFISH CAMBARUS-BARTONII-BARTONII TO ACID EXPOSURE IN SOUTHERN APPALACHIAN STREAMS SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID LOW ENVIRONMENTAL PH; 3 LIFE STAGES; ORCONECTES-RUSTICUS; TOXICOLOGICAL RESPONSES; PHYSIOLOGICAL-RESPONSES; SALVELINUS-FONTINALIS; CENTRAL ONTARIO; RAINBOW-TROUT; BROOK TROUT; BASE STATUS AB Intermolt adult and juvenile Cambarus bartonii bartonii (Fabricius) from southern Appalachian Mountains streams tolerated considerable acidity when acutely exposed to greatly reduced pH levels in laboratory bioassays. Tolerance increased with increasing size or age of crayfish. Ninety-six-hour exposures yielded LC50 values of pH 2.43, 2.56, and 2.85 for adults, advanced juveniles, and early juveniles, respectively. Lowering the water temperature increased the acid tolerance and survival time of intermolt adults during severe acidification (temperatures ranged from 20.2 to 13.3-degrees-C). Acid exposure to intermolt adults in soft water up to 96 h caused a linear decrease in hemolymph [Na]. Hemolymph [Ca] increased through 48 h and then returned to near pre-exposure levels. An initial increase in [K] was followed by a decrease to slightly below pre-exposure levels. Hemolymph [Mg] remained unchanged. No Ca was lost from carapaces. These observations indicate that occasional episodes of higher than normal acidity in southern Appalachian streams are not necessarily a threat to intermolt adult and juvenile C. b. bartonii. Nevertheless, gradually increasing acidity and loss of watershed buffering capacity could produce sublethal effects such as altered reproductive activity, or changes in early life history stages and more sensitive molt cycle stages, that could damage these populations. C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT FISHERIES & WILDLIFE SCI,US FISH & WILDLIFE SERV,BLACKSBURG,VA 24061. MICHIGAN STATE UNIV,DEPT ZOOL,E LANSING,MI 48824. NR 57 TC 20 Z9 20 U1 1 U2 9 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD JUN PY 1991 VL 69 IS 6 BP 1585 EP 1591 DI 10.1139/z91-222 PG 7 WC Zoology SC Zoology GA GH352 UT WOS:A1991GH35200020 ER PT J AU DENNIS, B MUNHOLLAND, PL SCOTT, JM AF DENNIS, B MUNHOLLAND, PL SCOTT, JM TI ESTIMATION OF GROWTH AND EXTINCTION PARAMETERS FOR ENDANGERED SPECIES SO ECOLOGICAL MONOGRAPHS LA English DT Review DE CALIFORNIA CONDOR; CONSERVATION BIOLOGY; DIFFUSION PROCESS; ENDANGERED SPECIES; EXPONENTIAL GROWTH; EXTINCTION; GRIZZLY BEAR; INVERSE GAUSSIAN DISTRIBUTION; KIRTLAND WARBLER; LAYSAN FINCH; LOGNORMAL DISTRIBUTION; PALILA; PARAMETER ESTIMATION; PUERTO-RICAN PARROT; STOCHASTIC DIFFERENTIAL EQUATION; STOCHASTIC POPULATION MODEL; WHOOPING CRANE; WIENER PROCESS ID INVERSE GAUSSIAN DISTRIBUTION; POPULATION-SIZE; RANDOM-ENVIRONMENTS; GRIZZLY BEARS; RESERVE FRAGMENTS; CONSERVATION; ABUNDANCE; MODELS; DEMOGRAPHY; STOCHASTICITY AB Survival or extinction of an endangered species is inherently stochastic. We develop statistical methods for estimating quantities related to growth rates and extinction probabilities from time series data on the abundance of a single population. The statistical methods are based on a stochastic model of exponential growth arising from the biological theory of age- or stage-structured populations. The model incorporates the so-called environmental type of stochastic fluctuations and yields a lognormal probability distribution of population abundance. Calculation of maximum likelihood estimates of the two unknown parameters in this model reduces to performing a simple linear regression. We describe techniques for rigorously testing and evaluating whether the model fits a given data set. Various growth- and extinction-related quantities are functions of the two parameters, including the continuous rate of increase, the finite rate of increase, the geometric finite rate of increase, the probability of reaching a lower threshold population size, the mean, median, and most likely time of attaining the threshold, and the projected population size. Maximum likelihood estimates and minimum variance unbiased estimates of these quantities are described in detail. We provide example analyses of data on the Whooping Crane (Grus americana), grizzly bear (Ursus arctos horribilis) in Yellowstone, Kirtland's Warbler (Dendroica kirtlandii), California Condor (Gymnogyps californianus), Puerto Rican Parrot (Amazona vittata), Palila (Loxioides balleui), and Laysan Finch (Telespyza cantans). The model results indicate a favorable outlook for the Whooping Crane, but long-term unfavorable prospects for the Yellowstone grizzly bear population and for Kirtland's Warbler. Results for the California Condor, in a retrospective analysis, indicate a virtual emergency existed in 1980. The analyses suggest that the Puerto Rican Parrot faces little risk of extinction from ordinary environmental fluctuations, provided intensive management efforts continue. However, the model does not account for the possibility of freak catastrophic events (hurricanes, fires, etc.), which are likely the most severe source of risk to the Puerto Rican Parrot, as shown by the recent decimation of this population by Hurricane Hugo. Model parameter estimates for the Palila and the Laysan Finch have wide uncertainty due to the extreme fluctuations in the population sizes of these species. In general, the model fits the example data sets well. We conclude that the model, and the associated statistical methods, can be useful for investigating various scientific and management questions concerning species preservation. C1 UNIV IDAHO,DEPT MATH & STAT,MOSCOW,ID 83843. MONTANA STATE UNIV,DEPT MATH SCI,BOZEMAN,MT 59717. UNIV IDAHO,COLL FORESTRY WILDLIFE & RANGE SCI,US FISH & WILDLIFE SERV,MOSCOW,ID 83843. RP DENNIS, B (reprint author), UNIV IDAHO,DEPT FOREST RESOURCES,MOSCOW,ID 83843, USA. NR 117 TC 381 Z9 393 U1 11 U2 119 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9615 J9 ECOL MONOGR JI Ecol. Monogr. PD JUN PY 1991 VL 61 IS 2 BP 115 EP 143 DI 10.2307/1943004 PG 29 WC Ecology SC Environmental Sciences & Ecology GA FM724 UT WOS:A1991FM72400001 ER PT J AU PRINGLE, CM TRISKA, FJ AF PRINGLE, CM TRISKA, FJ TI EFFECTS OF GEOTHERMAL GROUNDWATER ON NUTRIENT DYNAMICS OF A LOWLAND COSTA RICAN STREAM SO ECOLOGY LA English DT Article DE ALGAE; CHLOROPHYLL-A; COSTA-RICA; GEOTHERMAL; GROUNDWATER; NITROGEN; PHOSPHORUS; TRACER INJECTION; TROPICAL STREAM; VOLCANIC ID LOTIC PERIPHYTON GROWTH; 3RD-ORDER STREAM; FOREST; VEGETATION; RETENTION; TRANSPORT; BIOTA; WATER AB Spatial and temporal variability of surface and groundwater nutrient chemistry was contrasted between two tributaries of the Salto River, which drain the terminus of Pleistocene lava flows in the Atlantic slope foothills of Barva Volcano, Costa Rica. Some riparian zones along the Salto are saturated by subsurface inflows of phosphorus-rich, geothermal groundwater of the sodium-chloride-bicarbonate type. The heterogeneous pattern of solute-rich groundwater inflows results in dramatic differences in soluble reactive phosphorus (SRP) concentration between stream waters of two closely adjacent tributaries. SRP levels also vary dramatically in the water table and in soils across stream riparian zones on a scale of metres. The Salto River (SRP 50-200-mu-g/L) receives steady phosphorus-rich groundwater inflows that become diluted with increasing precipitation. The Pantano lacks these inputs and retains a low background SRP concentration (typically < 10-mu-g/L). SRP levels in waters of the Salto were strongly negatively correlated with discharge (r = - 0.86), while in the Pantano there was no correlation. In situ nutrient bioassays of algal periphyton growth indicated that both nitrate and SRP were at growth-saturating levles in the Salto while, in the Pantano, algal growth was phosphorus limited. The Pantano had a high retention capacity for phosphorus as measured through a whole-stream tracer injection experiment. SRP concentration was reduced by 17 and 94% of injected phosphate over 40 and 800 m reaches, respectively. Results indicate the important linkage between geothermal activity and hydrogeochemical features of the volcanic landscape and their role in regulating ecological processes in these streams. C1 US GEOL SURVEY,DIV WATER RESOURCES,MENLO PK,CA 94025. RP PRINGLE, CM (reprint author), CORNELL UNIV,ECOL & SYSTEMAT SECT,ITHACA,NY 14853, USA. RI Pringle, Catherine/I-1841-2012 NR 47 TC 58 Z9 59 U1 1 U2 7 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9658 J9 ECOLOGY JI Ecology PD JUN PY 1991 VL 72 IS 3 BP 951 EP 965 DI 10.2307/1940596 PG 15 WC Ecology SC Environmental Sciences & Ecology GA FM084 UT WOS:A1991FM08400018 ER PT J AU COMMEAU, JA VALENTINE, PC AF COMMEAU, JA VALENTINE, PC TI A METHOD FOR THE CONCENTRATION OF FINE-GRAINED RUTILE (TIO2) FROM SEDIMENT AND SEDIMENTARY-ROCKS BY CHEMICAL LEACHING SO ECONOMIC GEOLOGY AND THE BULLETIN OF THE SOCIETY OF ECONOMIC GEOLOGISTS LA English DT Note RP COMMEAU, JA (reprint author), US GEOL SURVEY,WOODS HOLE,MA 02543, USA. NR 12 TC 1 Z9 1 U1 0 U2 2 PU ECONOMIC GEOLOGY PUBL CO PI EL PASO PA UNIV TEXAS AT EL PASO ROOM 202 QUINN HALL, EL PASO, TX 79968 SN 0361-0128 J9 ECON GEOL BULL SOC JI Econ. Geol. Bull. Soc. Econ. Geol. PD JUN-JUL PY 1991 VL 86 IS 4 BP 878 EP 882 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FU929 UT WOS:A1991FU92900012 ER PT J AU JENNINGS, DP AF JENNINGS, DP TI BEHAVIORAL-ASPECTS OF COLD TOLERANCE IN BLACKCHIN TILAPIA, SAROTHERODON-MELANOTHERON, AT DIFFERENT SALINITIES SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE CICHLIDAE; CRITICAL THERMAL MINIMUM; SOCIAL BEHAVIOR; DOMINANCE HIERARCHY; EXOTIC FISH ID LETHAL TEMPERATURES AB Cold tolerance and behavioral responses of blackchin tilapia, Sarotherodon melanotheron, to rapidly decreasing temperatures were investigated at salinities of 5, 15, and 35 parts per thousand (ppt). Cold tolerance did not significantly differ with salinity or social rank. Mean temperatures were 10.7-degrees-C for beginning loss of equilibrium, 9.6-degrees-C for complete loss of equilibrium, and 6.9-degrees-C for death at all salinities. Behavioral activity declined with decreasing temperature and ceased between 10-12-degrees-C. Certain behavioral actions were significantly more frequent at 15 or 35 ppt salinity than at 5 ppt. The northward range expansion by introduced populations of the blackchin tilapia in the United States probably will be limited by its lower lethal temperature limits, but may also be affected by temperatures at which social behavior becomes disrupted. RP JENNINGS, DP (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,GAINESVILLE,FL 32606, USA. NR 35 TC 14 Z9 15 U1 0 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD JUN PY 1991 VL 31 IS 2 BP 185 EP 195 DI 10.1007/BF00001019 PG 11 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA FT718 UT WOS:A1991FT71800010 ER PT J AU CARROLL, JF RUSSEKCOHEN, E NICHOLS, JD HINES, JE AF CARROLL, JF RUSSEKCOHEN, E NICHOLS, JD HINES, JE TI POPULATION-DYNAMICS OF AMERICAN DOG TICKS (ACARI, IXODIDAE) ALONG PARK TRAILS SO ENVIRONMENTAL ENTOMOLOGY LA English DT Article DE ARACHNIDA; DERMACENTOR-VARIABILIS; CLOTH DRAG; PARK TRAILS ID DERMACENTOR-VARIABILIS ACARINA; CAPTURE-RECAPTURE MODELS AB We conducted a mark-recapture study in which drag-collected ticks were removed from some park trails weekly from April to July. Weekly survival rates (probability of surviving and remaining on the trails) were significantly lower on trails used heavily by hikers, horses, and pets than on trails used less frequently. Although usage was the only obvious difference among these trails, differences in weekly survival rate estimates may be attributable to differential success in acquiring hosts. The estimated probability of capturing a host-seeking tick located along a trail on a single drag was 0.20 on the drag alone, and 0.25 including the person dragging. When routes parallel to the trails and of equal lengths were dragged immediately after sampling the trails, only almost-equal-to 5% as many ticks (including ticks on the person dragging) were found off the trails as on them. We found no evidence of reduced tick numbers on removal trails, but this result should be considered inconclusive because the power of the discerning test was low. However, the data reported here provide insights into turnover rates of the adult Dermacentor variabilis population and effectiveness of the drag as a sampling device. C1 UNIV MARYLAND,DEPT ANIM SCI,COLLEGE PK,MD 20740. US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,US DEPT INTERIOR,LAUREL,MD 20708. RP CARROLL, JF (reprint author), USDA ARS,BELTSVILLE AGR RES CTR,LIVESTOCK & POULTRY SCI INST,LIVESTOCK INSECTS LAB,BELTSVILLE,MD 20705, USA. NR 26 TC 13 Z9 13 U1 1 U2 2 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 SN 0046-225X J9 ENVIRON ENTOMOL JI Environ. Entomol. PD JUN PY 1991 VL 20 IS 3 BP 922 EP 929 PG 8 WC Entomology SC Entomology GA FT888 UT WOS:A1991FT88800025 ER PT J AU LOVLEY, DR PHILLIPS, EJP LONERGAN, DJ AF LOVLEY, DR PHILLIPS, EJP LONERGAN, DJ TI ENZYMATIC VERSUS NONENZYMATIC MECHANISMS FOR FE(III) REDUCTION IN AQUATIC SEDIMENTS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID ORGANIC-MATTER MINERALIZATION; MICROBIAL IRON REDUCTION; FERRIC IRON; DISSIMILATORY REDUCTION; ANAEROBIC SEDIMENTS; MANGANESE OXIDES; OXIDATION; AVAILABILITY; DISSOLUTION; INHIBITION AB The potential for nonenzymatic reduction of Fe(III) either by organic compounds or by the development of a low redox potential during microbial metabolism was compared with direct, enzymatic Fe(III) reduction by Fe(III)-reducing microorganisms. At circumneutral pH, very few organic compounds nonenzymatically reduced Fe(III). In contrast, in the presence of the appropriate Fe(III)-reducing microorganisms, most of the organic compounds examined could be completely oxidized to carbon dioxide with the reduction of Fe(III). Even for those organic compounds that could nonenzymatically reduce Fe(III), microbial Fe(III) reduction was much more extensive. The development of a low redox potential during microbial fermentation did not result in nonenzymatic Fe(III) reduction. Model organic compounds were readily oxidized in Fe(III)-reducing aquifer sediments, but not in sterilized sediments. These results suggest that microorganisms enzymatically catalyze most of the Fe(III) reduction in the Fe(III) reduction zone of aquatic sediments and aquifers. RP LOVLEY, DR (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,430 NATL CTR,RESTON,VA 22092, USA. NR 51 TC 176 Z9 182 U1 4 U2 38 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD JUN PY 1991 VL 25 IS 6 BP 1062 EP 1067 DI 10.1021/es00018a007 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA FN925 UT WOS:A1991FN92500011 ER PT J AU SLACK, J AF SLACK, J TI 7TH ANNUAL MCKELVEY,V.E. FORUM - RENO, NEVADA, USA, 11-14 FEBRUARY 1991 SO EPISODES LA English DT Editorial Material RP SLACK, J (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT UNION GEOLOGICAL SCIENCES PI KEYWORTH PA C/O BRITISH GEOLOGICAL SURVEY, KEYWORTH, NOTTINGHAM, ENGLAND NG12 5GG SN 0705-3797 J9 EPISODES JI Episodes PD JUN PY 1991 VL 14 IS 2 BP 141 EP 142 PG 2 WC Geosciences, Multidisciplinary SC Geology GA GC807 UT WOS:A1991GC80700006 ER PT J AU BISCHOFF, JL HERBST, DB ROSENBAUER, RJ AF BISCHOFF, JL HERBST, DB ROSENBAUER, RJ TI GAYLUSSITE FORMATION AT MONO LAKE, CALIFORNIA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Letter AB The salinity of Mono Lake has steadily increased since 1941 from 50 parts per thousand to about 90 parts per thousand due to diversion of tributary streams. This increase has resulted in the newly discovered precipitation of gaylussite (Na2Ca(CO3)2 . 5H2O). Chemical modeling of the lake water using Pitzer equations suggests that gaylussite has been forming year round since about 1970 when the salinity first exceeded 80 parts per thousand, and that it was earlier forming intermittently at lower salinities in the winter shortly after diversion began, breaking down incongruently to aragonite during summers. Lake water appears to remain at a constant 9-fold supersaturation with aragonite at all salinities, perhaps buffered by monohydrocalcite which appears to be just at saturation for all salinities. Other saline lakes also appear to be buffered by monohydrocalcite. C1 SIERRA NEVADA AQUAT RES LAB,MAMMOTH LAKES,CA 93546. RP BISCHOFF, JL (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 22 TC 31 Z9 31 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD JUN PY 1991 VL 55 IS 6 BP 1743 EP 1747 DI 10.1016/0016-7037(91)90144-T PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FU772 UT WOS:A1991FU77200023 ER PT J AU SIMPSON, C AF SIMPSON, C TI A REINTERPRETATION OF THE TIMING, POSITION, AND SIGNIFICANCE OF PART OF THE SACRAMENTO MOUNTAINS DETACHMENT FAULT, SOUTHEASTERN CALIFORNIA SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID METAMORPHIC CORE COMPLEXES; EASTERN MOJAVE DESERT; WESTERN ARIZONA; EVOLUTION; DENUDATION; FOOTWALL; WHIPPLE; NEVADA; ORIGIN; UPLIFT AB A contact previously considered to be part of the Sacramento Mountains detachment fault (SDF), exposed in the Sacramento Mountains metamorphic core complex, is reinterpreted as an unconformity between Tertiary rhyolite of Eagle Peak and cataclastically deformed crystalline lower-plate rocks. This reinterpretation is based on outcrop-scale topographic relief and the absence of deformation along the base of the rhyolite, even where underlying rocks are severely deformed and altered. The rhyolite is dated at about 14.3 Ma. Lower-plate rocks of the SDF comprise gneiss intruded by granodiorite, tonalite, and leucogranite. Mylonitic fabrics are variably developed in lower-plate rocks and are cut by brittle shear zones that contain ultracataclasite, and by high- and low-angle faults. Upper-plate rocks include gneiss; nonmylonitic granodiorite, tonalite, and granite; and middle Miocene sedimentary and volcanic rocks. On the south side of Eagle Peak, a thick ultracataclasite zone dips about 30-degrees west, contains subhorizontal hematite-stained slickenlines, and is interpreted to be part of the SDF system. This ultracataclasite zone is uncomformably overlain by more gently dipping, undeformed, 14.3 Ma rhyolite of Eagle Peak. The unconformity records unroofing of a domed SDF after a period of 8 to 9 m.y. of progressive unloading of the lower plate in an evolving extensional shear zone. Extension on part of the SDF was accommodated by a system of high-angle, oblique-slip faults. C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT GEOL SCI,BLACKSBURG,VA 24061. US GEOL SURVEY,MENLO PK,CA 94025. RP SIMPSON, C (reprint author), JOHNS HOPKINS UNIV,DEPT EARTH & PLANETARY SCI,BALTIMORE,MD 21218, USA. NR 50 TC 15 Z9 15 U1 1 U2 3 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD JUN PY 1991 VL 103 IS 6 BP 751 EP 761 DI 10.1130/0016-7606(1991)103<0751:AROTTP>2.3.CO;2 PG 11 WC Geosciences, Multidisciplinary SC Geology GA FQ660 UT WOS:A1991FQ66000003 ER PT J AU MOORE, DE BYERLEE, JD AF MOORE, DE BYERLEE, JD TI COMPARATIVE GEOMETRY OF THE SAN-ANDREAS FAULT, CALIFORNIA, AND LABORATORY FAULT ZONES SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID STRIKE-SLIP FAULTS; EARTHQUAKE; GOUGE; DEFORMATION; EVOLUTION; AFTERSHOCKS; EXAMPLES; VELOCITY; BEHAVIOR; GARLOCK AB Textural examination of fault gouge deformed in triaxial friction experiments has revealed differences in the orientations of secondary shear sets between the stably sliding and stick-slip samples. In order to determine whether such differences can be identified in natural faults, maps of recently active breaks along the San Andreas fault from Point Arena to Cajon Pass, California, were examined to compare the types and orientations of secondary structures mapped in the creeping and locked sections. The fault zone was divided into 52 geometrically defined segments of uniform strike, which were then grouped into 7 sections: 4 straight and 2 curved sections, and Cholame Valley. One of the straight sections is the creeping section between San Juan Bautista and Cholame in central California; the rest of the sections are locked. Many of the gross geometric characteristics of the individual segments, such as length, width, and stepover size, reflect their position in either a straight or a curved section. In contrast, with respect to the orientations of the recent breaks within the segments, the single creeping section differs from all of the locked sections, both straight and curved, as follows: (1) the traces of recent breaks with a more westward orientation than the local strike of the fault zone (P traces) dominate over those with a more northward orientation (R traces) in the creeping section, whereas the opposite relationship holds in the locked sections, and (2) the more northward-oriented (R) traces make larger angles to the local strike of the fault zone in the locked sections than in the creeping section. The latter result is consistent with the orientations of R shears in our various laboratory samples. The former result was unexpected, because of the predominance of R shears in most laboratory samples, but a small number of samples are analogous to the creeping section in terms of their P-shear abundances, R-shear orientations, and sliding behavior. The causes of these distinguishing characteristics are not yet understood. RP MOORE, DE (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 60 TC 16 Z9 16 U1 0 U2 2 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD JUN PY 1991 VL 103 IS 6 BP 762 EP 774 DI 10.1130/0016-7606(1991)103<0762:CGOTSA>2.3.CO;2 PG 13 WC Geosciences, Multidisciplinary SC Geology GA FQ660 UT WOS:A1991FQ66000004 ER PT J AU BLAKELY, RJ JACHENS, RC AF BLAKELY, RJ JACHENS, RC TI REGIONAL STUDY OF MINERAL-RESOURCES IN NEVADA - INSIGHTS FROM 3-DIMENSIONAL ANALYSIS OF GRAVITY AND MAGNETIC-ANOMALIES SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article AB A three-dimensional interpretation of the basins of Nevada was developed based on statewide data bases of digital-gravity, magnetic, geologic, well, and topographic information. An iterative technique was applied to isostatic residual gravity anomalies in Nevada in order to define the location and shape of pre-Tertiary basement and to produce a gravity map that reflects variations of density within the pre-Tertiary basement. The dominant feature of the basement gravity of Nevada is an enormous area of low gravity that spans the entire state between latitudes 37-degrees-N and 40.5-degrees-N. This regional low strongly correlates with the distribution of middle and late Tertiary volcanic rocks and may reflect silicic intrusions within the mid-crust and upper crust that are the counterparts of volcanic rocks at the surface. Although 80% of Nevada is covered by Cenozoic deposits, these deposits are thicker than 1 km over only about 20% of the state. The remaining 60% of Nevada may have pre-Tertiary basement rocks within reach of current mineral-exploration techniques. Aeromagnetic profiles from the National Uranium Resource Evaluation (NURE) were analyzed in order to produce a map showing the location of shallow magnetic sources in Nevada. This analysis shows that 46% of the state has magnetic sources, generally Mesozoic and Cenozoic igneous rocks, within 1 km of the surface. A linear magnetic anomaly in north-central Nevada has been interpreted by others as a rift zone active during middle Miocene time. The rift also is evident in NURE magnetic profiles, but our interpretation suggests that the magnetic expression of the rift continues south-southeast with similar strike to at least 38-degrees-N and perhaps to the amagmatic zone (lat. 37-degrees-N). The survival since the middle Miocene of this narrow crustal feature, essentially linear over a distance of 500 km, is difficult to interpret in light of later Basin and Range deformation. Our analysis of gravity anomalies shows that many deep Cenozoic basins are located near the rift, yet only two basins cut across it, and at least five others change strike near the rift, as if to avoid it. The rift may have remained linear because it is associated with crustal structures that acted to resist subsequent deformation. RP US GEOL SURVEY, MENLO PK, CA 94025 USA. NR 24 TC 28 Z9 28 U1 0 U2 1 PU GEOLOGICAL SOC AMER, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0016-7606 EI 1943-2674 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD JUN PY 1991 VL 103 IS 6 BP 795 EP 803 DI 10.1130/0016-7606(1991)103<0795:RSOMRI>2.3.CO;2 PG 9 WC Geosciences, Multidisciplinary SC Geology GA FQ660 UT WOS:A1991FQ66000007 ER PT J AU DURRHEIM, RJ MOONEY, WD AF DURRHEIM, RJ MOONEY, WD TI ARCHEAN AND PROTEROZOIC CRUSTAL EVOLUTION - EVIDENCE FROM CRUSTAL SEISMOLOGY SO GEOLOGY LA English DT Article ID UPPER MANTLE STRUCTURE; SEISMIC-REFRACTION; CONTINENTAL-CRUST; GROWTH; LITHOSPHERE; AUSTRALIA; PROFILE AB Seismic-velocity models for Archean and Proterozoic provinces throughout the world are analyzed. The thickness of the crust in Archean provinces is generally found to be about 35 km (except at collisional boundaries), whereas Proterozoic crust has a significantly greater thickness of about 45 km and has a substantially thicker high-velocity (> 7.0 km/s) layer at the base. We consider two models that may explain these differences. The first model attributes the difference to a change in the composition of the upper mantle. The higher temperatures in the Archean mantle led to the eruption of komatitic lavas, resulting in an ultradepleted lithosphere unable to produce significant volumes of basaltic melt. Proterozoic crust developed above fertile mantle, and subsequent partial melting resulted in basaltic underplating and crustal inflation. In the second model, convection in the hot Archean mantle is considered to have been too turbulent to sustain stable long-lived subduction zones. By the Proterozoic the mantle had cooled sufficiently for substantial island and continental arcs to be constructed, and the high-velocity basal layer was formed by basaltic underplating. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP DURRHEIM, RJ (reprint author), UNIV WITWATERSRAND,DEPT GEOPHYS,JOHANNESBURG 2050,SOUTH AFRICA. NR 28 TC 138 Z9 144 U1 0 U2 24 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUN PY 1991 VL 19 IS 6 BP 606 EP 609 DI 10.1130/0091-7613(1991)019<0606:AAPCEE>2.3.CO;2 PG 4 WC Geology SC Geology GA FQ661 UT WOS:A1991FQ66100016 ER PT J AU TRIBBLE, GW AF TRIBBLE, GW TI UNDERWATER OBSERVATIONS OF ACTIVE LAVA FLOWS FROM KILAUEA VOLCANO, HAWAII SO GEOLOGY LA English DT Article ID GALAPAGOS RIFT; AXIAL VOLCANO AB Underwater observation of active submarine lava flows from Kilauea volcano, Hawaii, in March-June 1989 revealed both pillow lava and highly channelized lava streams flowing down a steep and unconsolidated lava delta. The channelized streams were 0.7-1.5 m across and moved at rates of 1-3 m/s. The estimated flux of a stream was 0.7 m3/s. Jets of hydrothermal water and gas bubbles were associated with the volcanic activity. The rapidly moving channelized lava streams represent a previously undescribed aspect of submarine volcanism. C1 UNIV HAWAII,SCH OCEAN & EARTH SCI & TECHNOL,DEPT OCEANOG,HONOLULU,HI 96822. RP TRIBBLE, GW (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,677 ALA MOANA BLVD,SUITE 415,HONOLULU,HI 96813, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 25 TC 49 Z9 50 U1 0 U2 5 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUN PY 1991 VL 19 IS 6 BP 633 EP 636 DI 10.1130/0091-7613(1991)019<0633:UOOALF>2.3.CO;2 PG 4 WC Geology SC Geology GA FQ661 UT WOS:A1991FQ66100023 ER PT J AU WHITNEY, JW SHROBA, RR AF WHITNEY, JW SHROBA, RR TI GEOMORPHIC ASSESSMENT OF LATE QUATERNARY VOLCANISM IN THE YUCCA MOUNTAIN AREA, SOUTHERN NEVADA - IMPLICATIONS FOR THE PROPOSED HIGH-LEVEL RADIOACTIVE-WASTE REPOSITORY - COMMENT SO GEOLOGY LA English DT Note RP WHITNEY, JW (reprint author), US GEOL SURVEY,FED CTR,MS 913,BOX 25046,DENVER,CO 80225, USA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUN PY 1991 VL 19 IS 6 BP 661 EP 661 DI 10.1130/0091-7613(1991)019<0661:CAROGA>2.3.CO;2 PG 1 WC Geology SC Geology GA FQ661 UT WOS:A1991FQ66100030 ER PT J AU MCKEOWN, FA HAMILTON, RM DIEHL, SF GLICK, EE AF MCKEOWN, FA HAMILTON, RM DIEHL, SF GLICK, EE TI DIAPIRIC ORIGIN OF THE BLYTHEVILLE AND PASCOLA ARCHES IN THE REELFOOT RIFT, EAST-CENTRAL UNITED-STATES - RELATION TO NEW MADRID SEISMICITY - REPLY SO GEOLOGY LA English DT Note C1 UN,GENEVA,SWITZERLAND. RP MCKEOWN, FA (reprint author), US GEOL SURVEY,DENVER,CO 80225, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD JUN PY 1991 VL 19 IS 6 BP 668 EP 669 PG 2 WC Geology SC Geology GA FQ661 UT WOS:A1991FQ66100039 ER PT J AU HUPP, CR SIMON, A AF HUPP, CR SIMON, A TI BANK ACCRETION AND THE DEVELOPMENT OF VEGETATED DEPOSITIONAL SURFACES ALONG MODIFIED ALLUVIAL CHANNELS SO GEOMORPHOLOGY LA English DT Article AB This paper describes the recovery of stable bank form and development of vegetated depositional surfaces along the banks of channelized West Tennessee streams. Most perennial stream in West Tennessee were straightened and dredged since the turn of the century. Patterns of fluvial ecological responses to channelization have previously been described by a six-stage model. Dendrogeomorphic (tree-ring) techniques allowed the determination of location, timing, amount, and rate of bank-sediment deposition. Channel cross sections and ecological analyses made at 101 locations along 12 streams, encompassing bends and straight reaches, show that channel and bank processes initially react vertically to channelization through downcutting. A depositional surface forms on banks once bed-degradation and heightened bank mass wasting processes have eased or slowed. The formation of this depositional surface marks the beginning of bank recovery from channelization. Dominating lateral processes, characteristic of stable or natural channels, return during the formation and expansion of the depositional surface, suggesting a relation with thalweg deflection, point-bar development, and meanderloop extension. Characteristic woody riparian vegetation begins to grow as this depositional surface develops and becomes part of the process and form of restabilizing banks. The depositional surface initially forms low on the bank and tends to maintain a slope of about 24-degrees. Mean accretion rates ranges from 5.9 cm/yr on inside bends to 0 cm/yr on most outside bends; straight reaches have a mean-accretion rate of 4.2 cm/yr. The relatively stable, convex upward, depositional surface expands and ultimately attaches to the flood plain. The time required for the recovery process to reach equilibrium averaged about 50 years. Indicative pioneer species of woody riparian vegetation include black willow, river birch, silver maple, and boxelder. Stem densities generally decrease with time after and initial flush of about 160 stems per 100 m2. Together bank accretion and vegetative regrowth appear to be the most important environmental processes involved in channel bank recovery from channelization or rejuvenation. RP HUPP, CR (reprint author), US GEOL SURVEY,430 NATL CTR,RESTON,VA 22092, USA. NR 0 TC 64 Z9 64 U1 3 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-555X J9 GEOMORPHOLOGY JI Geomorphology PD JUN PY 1991 VL 4 IS 2 BP 111 EP 124 DI 10.1016/0169-555X(91)90023-4 PG 14 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA FX526 UT WOS:A1991FX52600003 ER PT J AU DALRYMPLE, GB RYDER, G AF DALRYMPLE, GB RYDER, G TI AR-40 AR-39 AGES OF 6 APOLLO 15 IMPACT MELT ROCKS BY LASER STEP HEATING SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB We have obtained 15 high resolution (21-51 step) Ar-40/Ar-39 age spectra on six Apollo 15 impact melt rocks of different compositions using a continuous laser system on submilligram subsamples and on single crystal plagioclase clasts. Four of the six samples gave reproducible age spectra with well-defined intermediate temperature plateaus over 48% or more of the Ar-39 released; the plateaus are interpreted as crystallization ages. Samples 15304,7,69, 15294,6,21, and 15314,26,156 gave virtually identical plateau ages whose weighted mean is 3,870 +/- 6 Ma. These three melt rocks differ in composition and likely formed in three separate impact events. Sample 15356,9 gave replicate plateau ages that average 3,836 +/- 12 Ma and date a fourth and younger impact event. The age spectra for samples 15308,9 and 15414,3,36 increase with increasing increment temperature and may have been formed in or affected by impacts at about 2,700 Ma and 3,870 Ma, respectively. So far there continues to be no convincing evidence in the lunar record for impact melts older than about 3.9 Ga. C1 LUNAR & PLANETARY INST,HOUSTON,TX 77058. RP DALRYMPLE, GB (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 18 TC 15 Z9 15 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUN PY 1991 VL 18 IS 6 BP 1163 EP 1166 DI 10.1029/91GL01143 PG 4 WC Geosciences, Multidisciplinary SC Geology GA FR190 UT WOS:A1991FR19000045 ER PT J AU GOLDHABER, MB REYNOLDS, RL AF GOLDHABER, MB REYNOLDS, RL TI RELATIONS AMONG HYDROCARBON RESERVOIRS, EPIGENETIC SULFIDIZATION, AND ROCK MAGNETIZATION - EXAMPLES FROM THE SOUTH TEXAS COASTAL-PLAIN SO GEOPHYSICS LA English DT Article ID URANIUM DEPOSIT; SULFUR ISOTOPE; SULFIDE; ORIGIN; MINERALS; EVOLUTION; USA AB This paper focuses on the association between concentrations of iron disulfide (FeS2) minerals in the shallow subsurface and underlying hydrocarbon accumulations. Such FeS2 concentrations are the result of migration of either H2S or organic constituents from the underlying hydrocarbons. The H2S from reservoirs is produced inorganically from sulfate in the reservoir rocks at high temperature (> 90-degrees-C) and migrates to shallower beds to react inorganically with iron to form FeS2. Organic constituents from reservoirs, in contrast, provide nourishment for sulfate reducing bacteria in shallow relatively cool (< 90-degrees-C) beds. Sandstone in the Ray Point uranium district in Live Oak County, Texas contains abundant FeS2 which formed both from deep-seated H2S and from H2S produced in the shallow subsurface by bacteria that utilized organic materials from depth. Deep petroleum reservoirs were physically connected to near-surface (< 100 m) beds containing epigenetic FeS2 by the Oakville fault. Epigenetic iron sulfide formation occurred in at least four episodes over at least five million years. Evidence from the Ray Point district and elsewhere in Texas illustrates that sulfidization reactions have destroyed magnetic iron-titanium oxide minerals in the vicinity of major growth faults, resulting in a systematic decrease in magnetic susceptibility and magnitude of remanent magnetization in the vicinity of such faults. Growth faults which tap hydrocarbon deposits may be detectable using aeromagnetic methods. RP GOLDHABER, MB (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046 MS 973,DENVER,CO 80225, USA. NR 31 TC 21 Z9 23 U1 0 U2 5 PU SOC EXPLORATION GEOPHYSICISTS PI TULSA PA 8801 S YALE ST, TULSA, OK 74137 SN 0016-8033 J9 GEOPHYSICS JI Geophysics PD JUN PY 1991 VL 56 IS 6 BP 748 EP 757 DI 10.1190/1.1443092 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FQ073 UT WOS:A1991FQ07300001 ER PT J AU JORGENSEN, DG AF JORGENSEN, DG TI ESTIMATING GEOHYDROLOGIC PROPERTIES FROM BOREHOLE-GEOPHYSICAL LOGS SO GROUND WATER MONITORING AND REMEDIATION LA English DT Article AB Borehole-geophysical logs can be used to estimate geohydrologic properties based on in situ measurement of rock and water properties. Estimates of properties of both formation and water, such as coefficient of diffusion, formation factor, cementation exponent, hydraulic conductivity, irreducible water content and specific yield can be assessed from borehole-geophysical data and selected algorithms and graphs. Water properties, such as resistivity, sodium chloride contration, viscosity and density, can also be estimated using data from borehole-geophysical logs. Water resistivity using the spontaneous-potential method can be estimated if an empirical correction for fresh water is applied. Estimates of formation properties, such as porosity and permeability, can also be made using borehole-geophysical data. RP JORGENSEN, DG (reprint author), US GEOL SURVEY,NATL DRILLING CO,GROUND WATER RES PROJECT,POB 15287,AL AIN,U ARAB EMIRATES. NR 20 TC 3 Z9 3 U1 0 U2 0 PU GROUND WATER PUBLISHING CO PI COLUMBUS PA 2600 GROUND WATER WAY, COLUMBUS, OH 43219 SN 1069-3629 J9 GROUND WATER MONIT R JI Ground Water Monit. Remediat. PD SUM PY 1991 VL 11 IS 3 BP 123 EP 129 DI 10.1111/j.1745-6592.1991.tb00388.x PG 7 WC Water Resources SC Water Resources GA FY222 UT WOS:A1991FY22200007 ER PT J AU MOSS, ME TASKER, GD AF MOSS, ME TASKER, GD TI AN INTERCOMPARISON OF HYDROLOGICAL NETWORK-DESIGN TECHNOLOGIES SO HYDROLOGICAL SCIENCES JOURNAL-JOURNAL DES SCIENCES HYDROLOGIQUES LA English DT Article AB Two network-design technologies are compared by random sub-sampling of actual streamflow data. The technologies, Network Analysis for Regional Information (NARI) and Network Analysis Using Generalized Least Squares (NAUGLS), have a common objective, viz. to maximize regional information within a limited budget and time horizon. The data used for intercomparison are from a network of 146 streamgauges in the central part of the United States. In general, the results for the illustrative example indicate that the NAUGLS method conveys more information than the NARI method to the network designer interested in maximizing regional information about mean annual flows with a limited budget. RP MOSS, ME (reprint author), US GEOL SURVEY,1675 W ANKLAM RD,TUCSON,AZ 85745, USA. NR 0 TC 25 Z9 25 U1 0 U2 0 PU IAHS PRESS, INST HYDROLOGY PI WALLINGFORD PA C/O SARAH CAGE, WALLINGFORD, ENGLAND OX10 8BB SN 0262-6667 J9 HYDROLOG SCI J JI Hydrol. Sci. J.-J. Sci. Hydrol. PD JUN PY 1991 VL 36 IS 3 BP 209 EP 221 DI 10.1080/02626669109492504 PG 13 WC Water Resources SC Water Resources GA FN276 UT WOS:A1991FN27600001 ER PT J AU REIMNITZ, E HAYDEN, E MCCORMICK, M BARNES, PW AF REIMNITZ, E HAYDEN, E MCCORMICK, M BARNES, PW TI PRELIMINARY-OBSERVATIONS ON COASTAL SEDIMENT LOSS THROUGH ICE RAFTING IN LAKE-MICHIGAN SO JOURNAL OF COASTAL RESEARCH LA English DT Article DE COASTAL EROSION; SEDIMENT TRANSPORT; ICE TRANSPORT; GREAT LAKES AB Knowledge of sediment content in drifting coastal ice was combined with aerial observations, ship-board ice sampling, and studies of LANDSAT images to show that ice rafting of sand is an important mechanism influencing processes of coastal erosion and basin-deposition in southern Lake Michigan. During winter, the central lake usually remains open, while sand-charged ice formed in coastal waters in displaced lakeward from the western shore in long, sinuous bands by offshore winds. Under some conditions, these ice streamers are dissipated within 2 to 20 km from the coast. This occurred during offshore collection of ice-rafted sand and gravel, demonstrating a net loss of beach sand from the windward shore to deep water. Under other conditions, ice streamers can cross the lake, leading to ice accumulations at the downwind or lee shore. Northwesterly winds dominate winter weather, so ice accumulations form mainly in the southeastern end of the lake, where they ultimately melt. Thus, ice rafting may be partly responsible for net sediment progradation at this southeastern, lee shore during the last few thousand years, and adds course grains to basin muds. RP REIMNITZ, E (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 14 TC 12 Z9 12 U1 0 U2 3 PU COASTAL EDUCATION & RESEARCH FOUNDATION PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 SN 0749-0208 J9 J COASTAL RES JI J. Coast. Res. PD SUM PY 1991 VL 7 IS 3 BP 653 EP 664 PG 12 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA FW195 UT WOS:A1991FW19500006 ER PT J AU CASTRO, G WUNDER, BA KNOPF, FL AF CASTRO, G WUNDER, BA KNOPF, FL TI TEMPERATURE-DEPENDENT LOSS OF MASS BY SHOREBIRDS FOLLOWING CAPTURE SO JOURNAL OF FIELD ORNITHOLOGY LA English DT Article ID DUNLINS; WADERS; MOLT AB It is well established that birds lose mass following capture. In this paper the effects of bird species and temperature on mass loss are examined, and it is shown that mass loss after capture is independent of bird species, but strongly influenced by temperature, especially above a threshold of about 30 C. Data on body mass must be collected immediately after capture to minimize this potential bias, especially on hot days. C1 COLORADO STATE UNIV,DEPT BIOL,FT COLLINS,CO 80523. US FISH & WILDLIFE SERV,NATL ECOL RES CTR,FT COLLINS,CO 80525. NR 13 TC 12 Z9 14 U1 0 U2 1 PU ASSOC FIELD ORNITHOLOGISTS PI BELOIT PA BELOIT COLLEGE, DEPT BIOLOGY, 700 COLLEGE ST, BELOIT, WI 53511 SN 0273-8570 J9 J FIELD ORNITHOL JI J. Field Ornithol. PD SUM PY 1991 VL 62 IS 3 BP 314 EP 318 PG 5 WC Ornithology SC Zoology GA GH322 UT WOS:A1991GH32200004 ER PT J AU MORING, JR MORING, SW AF MORING, JR MORING, SW TI SHORT-TERM MOVEMENTS OF LARVAL AND JUVENILE LUMPFISH, CYCLOPTERUS-LUMPUS L IN TIDEPOOLS SO JOURNAL OF FISH BIOLOGY LA English DT Article DE CYCLOPTERUS-LUMPUS; TIDEPOOLS; MOVEMENTS ID OLIGOCOTTUS-MACULOSUS; PREDATION; HABITS; FISHES; BAY; USA RP MORING, JR (reprint author), UNIV MAINE,US FISH & WILDLIFE SERV,DEPT ZOOL,ORONO,ME 04469, USA. NR 24 TC 7 Z9 7 U1 2 U2 11 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD JUN PY 1991 VL 38 IS 6 BP 845 EP 850 DI 10.1111/j.1095-8649.1991.tb03624.x PG 6 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA FT488 UT WOS:A1991FT48800006 ER PT J AU HUBERT, WA OSHEA, DT AF HUBERT, WA OSHEA, DT TI TEMPORAL PATTERNS OF THE SMALL FISHES IN THE LITTORAL-ZONE OF GRAYROCKS RESERVOIR, WYOMING SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article ID LAKE; ASSEMBLAGES; ABUNDANCE; WISCONSIN AB The abundance and sizes of small fishes in littoral areas of Grayrocks Reservoir, Wyoming, were assessed from June through August 1990. Of the 14 species collected; 11 were found in numbers sufficient to assess temporal trends. Six species co-occurred during June; all species, except fathead minnow, occupied the littoral areas during July; eight species co-occurred at the end of August. RP HUBERT, WA (reprint author), UNIV WYOMING,US FISH & WILDLIFE SERV,WYOMING COOPERAT FISH & WILDLIFE RES UNIT,LARAMIE,WY 82071, USA. NR 16 TC 5 Z9 5 U1 1 U2 3 PU OIKOS PUBL INC PI LA CROSSE PA PO BOX 2558, LA CROSSE, WI 54601 SN 0270-5060 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD JUN PY 1991 VL 6 IS 2 BP 107 EP 113 DI 10.1080/02705060.1991.9665284 PG 7 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA GB708 UT WOS:A1991GB70800001 ER PT J AU CARTER, V RYBICKI, NB HAMMERSCHLAG, R AF CARTER, V RYBICKI, NB HAMMERSCHLAG, R TI EFFECTS OF SUBMERSED MACROPHYTES ON DISSOLVED-OXYGEN, PH, AND TEMPERATURE UNDER DIFFERENT CONDITIONS OF WIND, TIDE, AND BED STRUCTURE SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article AB Seasonal data on diurnal dissolved-oxygen concentration (DO), pH, temperature and chlorophyll-a were collected and species composition and vertical structure of macrophyte beds were analyzed in the tidal Potomac River during the 1987 growing season. The relationships among these variables and physical and climatic factors were analyzed. Elevated surface temperatures, DO and pH were found in macrophyte beds in June and August; surface temperatures were also elevated in the dense Hydrilla verticillata dominated bed in October-November after senescence had begun. Bottom DO, pH and temperature were lower than surface values. Bottom temperatures in vegetated sites were highly variable compared with bottom temperatures in unvegetated sites. Tide, wind, vegetative structure and available sunshine interacted in a complex fashion to control the magnitude of the diurnal DO, pH and temperature and the stratification of DO, pH and temperature with depth in vegetated sites. Fluctuations in DO and pH at unvegetated sites were the result of phytoplankton photosynthesis and proximity to beds of vegetation as well as wind and available sunshine. The tidal cycle drove the daily exchange of water between macrophyte beds and adjacent water. C1 CTR URBAN ECOL,NATL PK SERV,WASHINGTON,DC 20242. RP CARTER, V (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 16 TC 25 Z9 25 U1 3 U2 15 PU OIKOS PUBL INC PI LA CROSSE PA PO BOX 2558, LA CROSSE, WI 54601 SN 0270-5060 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD JUN PY 1991 VL 6 IS 2 BP 121 EP 133 DI 10.1080/02705060.1991.9665286 PG 13 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA GB708 UT WOS:A1991GB70800003 ER PT J AU SAVINO, JF MILLER, JE AF SAVINO, JF MILLER, JE TI CRAYFISH (ORCONECTES-VIRILIS) FEEDING ON YOUNG LAKE TROUT (SALVELINUS-NAMAYCUSH) - EFFECT OF ROCK SIZE SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article ID PREDATION; DYNAMICS; REEF AB In laboratory studies, we quantified predation rates of crayfish (Orconectes virilis) on the eggs and sac fry of lake trout (Salvelinus namaycush) and a surrogate species, rainbow trout (Oncorhynchus mykiss), dispersed among different sized substrates (bare bottom, gravel, cobble, large rocks). Predation was most severe when no rocks were present. Feeding rate then decreased as the substrate changed from large rocks to cobble to gravel. Crayfish predation rate did not change with prey type -- rainbow trout and lake trout eggs or sac fry. Crayfish foraging in large tanks containing cobble averaged about two eggs or sac fry per day. In most instances, crayfish would have little impact on lake trout egg survival. Only in lake trout spawning grounds with relatively low egg densities, large crayfish populations, and cobble or large rock substrate, would crayfish be expected to have some impact on lake trout egg survival. RP SAVINO, JF (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105, USA. NR 28 TC 46 Z9 49 U1 0 U2 12 PU OIKOS PUBL INC PI LA CROSSE PA PO BOX 2558, LA CROSSE, WI 54601 SN 0270-5060 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD JUN PY 1991 VL 6 IS 2 BP 161 EP 170 DI 10.1080/02705060.1991.9665290 PG 10 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA GB708 UT WOS:A1991GB70800007 ER PT J AU DIETER, CD AF DIETER, CD TI WATER TURBIDITY IN TILLED AND UNTILLED PRAIRIE WETLANDS SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article AB Water turbidity was compared between 54 tilled prairic potholc wetlands, 12 partially tilled wetlands and 52 untilled wetlands in South Dakota. Specific differences in sedimentation as measured by turbidity were indicated. Turbidity was significantly higher in tilled than in partially or untilled wetlands (P < 0.01). Average turbidity was 24 times greater in tilled than in untilled wetlands. There was no significant difference in turbidity between partially tilled and untilled wetlands. Turbidity measurement may be a useful tool for estimating relative sedimentation rates. Current sedimentation rates of tilled wetlands may cause them to be filled in a relatively short period of time. RP DIETER, CD (reprint author), US FISH & WILDLIFE SERV,POB 2206,BROOKINGS,SD 57007, USA. NR 18 TC 8 Z9 9 U1 0 U2 1 PU OIKOS PUBL INC PI LA CROSSE PA PO BOX 2558, LA CROSSE, WI 54601 SN 0270-5060 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD JUN PY 1991 VL 6 IS 2 BP 185 EP 189 DI 10.1080/02705060.1991.9665292 PG 5 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA GB708 UT WOS:A1991GB70800009 ER PT J AU BARKO, JW SMART, RM MCFARLAND, DG AF BARKO, JW SMART, RM MCFARLAND, DG TI INTERACTIVE EFFECTS OF ENVIRONMENTAL-CONDITIONS ON THE GROWTH OF SUBMERSED AQUATIC MACROPHYTES SO JOURNAL OF FRESHWATER ECOLOGY LA English DT Article ID INORGANIC CARBON; PLANTS; LIGHT; AVAILABILITY; ZONATION AB Variations in the growth of dioecious Hydrilla verticillata (L.f.) Royle and Vallisneria americana Michx. were examined in a greenhouse under each of two levels (low and high) of light availability, sediment fertility, and inorganic carbon supply. Under low light (ca. 125 uE/m2/s at midday), effects of sediment fertility and inorganic carbon availability on biomass production were relatively minor. Maximum biomass production in both species was achieved under high light (ca. 550 uE/m2/s at midday) on fertile sediment with a ten-fold increase in ambient CO2 supply. However, with other treatment combinations, biomass and morphological responses differed considerably between species. Biomass production in Hydrilla was most responsive to CO2 supply, while in Vallisneria, production was most responsive to sediment fertility. Shoot elongation in response to low light was much more pronounced in Hydrilla than in Vallisneria. Under high light, Hydrilla maximized shoot density (number) with an accompanying increase in biomass production. In Vallisneria, however, shoot (plant) density diminished with increased biomass production under both light levels. In nature, the outcome of competition between these two important submersed macrophyte species may be influenced significantly by interactions among the studied variables. C1 US FISH & WILDLIFE SERV,CTR ENVIRONM MANAGEMENT TECH,ONALASKA,WI 54650. RP BARKO, JW (reprint author), USA,ENGINEER WATERWAYS EXPT STN,ENVIRONM LAB,VICKSBURG,MS 39180, USA. NR 18 TC 27 Z9 31 U1 3 U2 13 PU OIKOS PUBL INC PI LA CROSSE PA PO BOX 2558, LA CROSSE, WI 54601 SN 0270-5060 J9 J FRESHWATER ECOL JI J. Freshw. Ecol. PD JUN PY 1991 VL 6 IS 2 BP 199 EP 207 DI 10.1080/02705060.1991.9665294 PG 9 WC Ecology; Limnology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA GB708 UT WOS:A1991GB70800011 ER PT J AU BOWN, TM ROSE, KD AF BOWN, TM ROSE, KD TI EVOLUTIONARY RELATIONSHIPS OF A NEW GENUS AND 3 NEW SPECIES OF OMOMYID PRIMATES (WILLWOOD FORMATION, LOWER EOCENE, BIGHORN BASIN, WYOMING) SO JOURNAL OF HUMAN EVOLUTION LA English DT Article DE NEW PRIMATE TAXA; OMOMYIDAE; IMMIGRATION; DIPHYLY; TATMANIUS; ARAPAHOVIUS; STEINIUS; EOCENE PRIMATES RP BOWN, TM (reprint author), US GEOL SURVEY,PALEONTOL & STRATIG BRANCH,MAIL STOP 919,DENVER,CO 80225, USA. NR 25 TC 16 Z9 17 U1 1 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0047-2484 J9 J HUM EVOL JI J. Hum. Evol. PD JUN PY 1991 VL 20 IS 6 BP 465 EP 480 DI 10.1016/0047-2484(91)90020-V PG 16 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA FT010 UT WOS:A1991FT01000002 ER PT J AU WALKER, JF AF WALKER, JF TI ACCURACY OF SELECTED TECHNIQUES FOR ESTIMATING ICE-AFFECTED STREAMFLOW SO JOURNAL OF HYDRAULIC ENGINEERING-ASCE LA English DT Article AB This paper compares the accuracy of selected techniques for estimating streamflow during ice-affected periods. The techniques are classified into two categories-subjective and analytical-depending on the degree of judgment required. Discharge measurements have been made at three streamflow-gauging sites in Iowa during the 1987-88 winter and used to establish a baseline streamflow record for each site. Using data based on a simulated six-week field-trip schedule, selected techniques are used to estimate discharge during the ice-affected periods. For the subjective techniques, three hydrographers have independently compiled each record. Three measures of performance are used to compare the estimated streamflow records with the baseline streamflow records: the average discharge for the ice-affected period, and the mean and standard deviation of the daily errors. Based on average ranks for three performance measures and the three sites, the analytical and subjective techniques are essentially comparable. For two of the three sites. Kruskal-Wallis one-way analysis of variance detects significant differences among the three hydrographers for the subjective methods, indicating that the subjective techniques are less consistent than the analytical techniques. The results suggest analytical techniques may be viable tools for estimating discharge during periods of ice effect, and should be developed further and evaluated for sites across the United States. RP WALKER, JF (reprint author), US GEOL SURVEY,6417 NORMANDY LANE,MADISON,WI 53719, USA. NR 17 TC 3 Z9 3 U1 0 U2 2 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9429 J9 J HYDRAUL ENG-ASCE JI J. Hydraul. Eng.-ASCE PD JUN PY 1991 VL 117 IS 6 BP 697 EP 712 DI 10.1061/(ASCE)0733-9429(1991)117:6(697) PG 16 WC Engineering, Civil; Engineering, Mechanical; Water Resources SC Engineering; Water Resources GA FN171 UT WOS:A1991FN17100002 ER PT J AU MCCABE, GJ WOLOCK, DM AF MCCABE, GJ WOLOCK, DM TI DETECTABILITY OF THE EFFECTS OF A HYPOTHETICAL TEMPERATURE INCREASE ON THE THORNTHWAITE MOISTURE INDEX SO JOURNAL OF HYDROLOGY LA English DT Article ID ATMOSPHERIC CO2; CLIMATE AB Climatic changes that result from increasing concentrations of atmospheric carbon dioxide may affect the availability of water for vegetation, groundwater recharge, runoff, and human consumption. Most studies of the effects of climatic change on water resources focus on changes in mean characteristics of hydrologic variables and do not consider the effects of these changes amid natural climatic variability. In this study, the Thornthwaite moisture index, an index of the supply of water in an area (precipitation) relative to the climatic demand for water (potential evapotranspiration), was used to examine the effects of a hypothetical increase in air temperature on moisture conditions in the United States. The effects of a gradual increase in air temperature at the rate of 4-degrees-C per 100 years, with no accompanying change in precipitation, was used to induce a change in Thornthwaite moisture index values for the United States in order to: (i) determine the relation between natural variability in climate and the time needed for significant trends in the moisture index to occur in response to hypothetical warming; (ii) identify the characteristics of areas (e.g. wet/cool, hot/dry etc.) that are most likely to be the first to experience significant changes in the moisture index given the hypothetical temperature increase. The increased temperature resulted in increased potential evapotranspiration and a decrease in the moisture index across the United States. Decreases in the moisture index were greatest in cool/wet regions and least in hot/dry regions. The time required to detect significant trends in the moisture index was a function of both the magnitude of change in the moisture index and the natural year-to-year variability of the moisture index. In general, when the ratio of the magnitude of change in the moisture index to the magnitude of variability was large, the time required to detect significant trends was short. This ratio was largest in cool/wet regions resulting in the shortest detection times. RP MCCABE, GJ (reprint author), US GEOL SURVEY,810 BEAR TAVERN RD,TRENTON,NJ 08628, USA. NR 19 TC 8 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JUN PY 1991 VL 125 IS 1-2 BP 25 EP 35 DI 10.1016/0022-1694(91)90081-R PG 11 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA FR898 UT WOS:A1991FR89800002 ER PT J AU FORESTER, RM AF FORESTER, RM TI OSTRACODE ASSEMBLAGES FROM SPRINGS IN THE WESTERN UNITED-STATES - IMPLICATIONS FOR PALEOHYDROLOGY SO MEMOIRS OF THE ENTOMOLOGICAL SOCIETY OF CANADA LA English DT Article AB Ostracodes are a diverse group of marine and continental crustaceans that have radiated into virtually all oxygenated aquatic environments that persist for more than about a month. Continental ostracodes live in both surface water and groundwater. Ostracodes living in springs and seeps have typically been the subject of systematic rather than ecologic studies. These taxa may or may not occur in other surface-water bodies. Similarly, lacustrine taxa may or may not be found in springs. Spring taxa occurring in other surface waters are often found in ponds, marshes, streams, or on the edges of lakes where groundwater discharge is important. Groundwater discharge, unlike lake water, shows limited and predictable variability in chemistry and temperature during the year. That level of variability relative to lake water may define particular ostracode environmental gradients. The gradients would range from stable, high-volume discharge springs occupied principally by spring species to high variability lakes occupied largely by lacustrine species. Ostracode occurrences may also be described by parameters such as temperature, solute (dissolved ion) composition, solute concentration (salinity, conductivity, ionic strength), and calcite saturation indices. A plot of these parameters associated with the presence of a taxon illustrates its physiologic response to the environment, a field. Three general fields bounded by chemical parameters are delineated by existing data. Those fields are as follows: (1) a restricted range and (2) a full range of fresh water, and (3) both fresh and saline water. Fields bounded by temperature and chemistry are also recognized. The fields also offer a way of describing ostracode occurrences in terms of hydrogeology and climate. If ostracode occurrences are limited by major chemical and physical properties of the aquatic environment, then their habitat may be defined by certain physical-chemical principles. The same physical-chemical principles must apply to the past. The ecology of extinct taxa may, therefore, be defined in the same environmental terms as those for extant taxa. RP FORESTER, RM (reprint author), US GEOL SURVEY,MS 919 BPS,DENVER,CO 80225, USA. NR 0 TC 55 Z9 56 U1 0 U2 4 PU ENTOMOL SOC CANADA PI OTTAWA PA 393 WINSTON AVE, OTTAWA ON K2A 1Y8, CANADA SN 0071-075X J9 MEM ENTOMOL SOC CAN JI Mem. Entomol. Soc. Can. PD SUM PY 1991 IS 155 BP 181 EP 201 PG 21 WC Entomology SC Entomology GA FU071 UT WOS:A1991FU07100011 ER PT J AU LOVLEY, DR AF LOVLEY, DR TI DISSIMILATORY FE(III) AND MN(IV) REDUCTION SO MICROBIOLOGICAL REVIEWS LA English DT Review ID FERRIC IRON REDUCTION; EASTERN EQUATORIAL PACIFIC; FRESH-WATER SEDIMENTS; DEEP-SEA SEDIMENTS; ANAEROBIC MICROBIAL DISSOLUTION; ORGANIC-MATTER MINERALIZATION; COASTAL MARINE-SEDIMENTS; MANGANESE REDUCTION; LAKE-SEDIMENTS; THIOBACILLUS-FERROOXIDANS AB The oxidation of organic matter coupled to the reduction of Fe(III) or Mn(IV) is one of the most important biogeochemical reactions in aquatic sediments, soils, and groundwater. This process, which may have been the first globally significant mechanism for the oxidation of organic matter to carbon dioxide, plays an important role in the oxidation of natural and contaminant organic compounds in a variety of environments and contributes to other phenomena of widespread significance such as the release of metals and nutrients into water supplies, the magnetization of sediments, and the corrosion of metal. Until recently, much of the Fe(III) and Mn(IV) reduction in sedimentary environments was considered to be the result of nonenzymatic processes. However, microorganisms which can effectively couple the oxidation of organic compounds to the reduction of Fe(III) or Mn(IV) have recently been discovered. With Fe(III) or Mn(IV) as the sole electron acceptor, these organisms can completely oxidize fatty acids, hydrogen, or a variety of monoaromatic compounds. This metabolism provides energy to support growth. Sugars and amino acids can be completely oxidized by the cooperative activity of fermentative microorganisms and hydrogen- and fatty-acid-oxidizing Fe(III) and Mn(IV) reducers. This provides a microbial mechanism for the oxidation of the complex assemblage of sedimentary organic matter in Fe(III)- or Mn(IV)-reducing environments. The available evidence indicates that this enzymatic reduction of Fe(III) or Mn(IV) accounts for most of the oxidation of organic matter coupled to reduction of Fe(III) and Mn(IV) in sedimentary environments. Little is known about the diversity and ecology of the microorganisms responsible for Fe(III) and Mn(IV) reduction, and only preliminary studies have been conducted on the physiology and biochemistry of this process. RP LOVLEY, DR (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,430 NATL CTR,RESTON,VA 22092, USA. NR 342 TC 1010 Z9 1071 U1 20 U2 237 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0146-0749 J9 MICROBIOL REV JI Microbiol. Rev. PD JUN PY 1991 VL 55 IS 2 BP 259 EP 287 PG 29 WC Microbiology SC Microbiology GA FP775 UT WOS:A1991FP77500005 PM 1886521 ER PT J AU LAUER, DT ESTES, JE JENSEN, JR GREENLEE, DD AF LAUER, DT ESTES, JE JENSEN, JR GREENLEE, DD TI INSTITUTIONAL ISSUES AFFECTING THE INTEGRATION AND USE OF REMOTELY SENSED DATA AND GEOGRAPHIC INFORMATION-SYSTEMS SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article AB The developers as well as the users of remotely sensed data and geographic information system (GIS) techniques are associated with nearly all types of institutions in government, industry, and academia. Individuals in these various institutions often find the barriers to accepting remote sensing and GIS are not necessarily technical in nature, but can be attributed to the institutions themselves. Several major institutional issues that affect the technologies of remote sensing and GIS are data availability, data marketing and costs, equipment availability and costs, standards and practices, education and training, and organizational infrastructures. Not only are problems associated with these issues identified, but needs and opportunities also are discussed. An agenda of suggested research topics is presented that relates to problems associated with data, equipment, standards, education/training, and organization structures. With a greater focus of research on institutional issues, the understanding, integration, and use of remote sensing and GIS technologies could be enhanced. C1 UNIV CALIF SANTA BARBARA,SANTA BARBARA,CA 93106. UNIV S CAROLINA,COLUMBIA,SC 29208. RP LAUER, DT (reprint author), US GEOL SURVEY,EROS DATA CTR,SIOUX FALLS,SD 57198, USA. NR 36 TC 4 Z9 4 U1 1 U2 5 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD JUN PY 1991 VL 57 IS 6 BP 647 EP 654 PG 8 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA FP856 UT WOS:A1991FP85600008 ER PT J AU EHLERS, M GREENLEE, D SMITH, T STAR, J AF EHLERS, M GREENLEE, D SMITH, T STAR, J TI INTEGRATION OF REMOTE-SENSING AND GIS - DATA AND DATA ACCESS SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID GEOGRAPHIC INFORMATION-SYSTEMS AB The integration of remote sensing tools and technology with the spatial analysis orientation of geographic information systems is a complex task. In this paper, we focus on the issues of making data available and useful to the user. In part, this involves a set of problems which reflect on the physical and logical structures used to encode the data. At the same time, however, the mechanisms and protocols which provide information about the data, and which maintain the data through time, have become increasingly important. We discuss these latter issues from the viewpoint of the functions which must be provided by archives of spatial data. C1 US GEOL SURVEY, EROS DATA CTR, SIOUX FALLS, SD 57198 USA. UNIV CALIF SANTA BARBARA, NATL CTR GEOG INFORMAT & ANAL, SANTA BARBARA, CA 93106 USA. RP INT INST AEROSP SURVEY & EARTH SCI, ITC, DEPT GEOINFORMAT, ENSCHEDE, NETHERLANDS. NR 43 TC 25 Z9 25 U1 0 U2 2 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 USA SN 0099-1112 EI 2374-8079 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD JUN PY 1991 VL 57 IS 6 BP 669 EP 675 PG 7 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA FP856 UT WOS:A1991FP85600010 ER PT J AU TERHUNE, CL HARDEN, JW AF TERHUNE, CL HARDEN, JW TI SEASONAL-VARIATIONS OF CARBON-DIOXIDE CONCENTRATIONS IN STONY, COARSE-TEXTURED DESERT SOILS OF SOUTHERN NEVADA, USA SO SOIL SCIENCE LA English DT Article ID ISOTOPIC COMPOSITION; MODEL; BASIN AB Knowledge of carbon dioxide concentration in desert soils is required in theoretical models of the development of pedogenic and ground-water calcium carbonate. Most studies have concentrated on medium- to fine-textured soils in temperature to humid environments. Very little data exist for CO2 concentrations in stony, coarse-textured deposits such as those making up alluvial fans and fluvial terraces. The purpose of this study was to obtain CO2 concentration data in stony, coarse-textured, uncultivated soils in a desert environment. Soil gas samples were collected from two sites - Yucca Wash and Rock Valley - at the Nevada Test Site in southern Nevada between June 1985 and June 1986 to determine soil CO2 concentrations and their seasonal and depth variations in the soil profile. Soil CO2 concentrations ranged from 0.03 volume percent in winter and summer to 0.25 volume percent in spring. During the summer, fall, and winter, CO2 concentrations were close to atmospheric levels and varied randomly with depth. In spring, CO2 varied with root density, highest concentrations occurring between 40 and 80 cm of depth. Maximum CO2 values decrease and occur at progressively deeper levels toward the end of spring. Biological activity appears to be limited throughout the year because of the arid climate. During the winter and spring, soil CO2 appears to be more dependent on temperature than moisture, whereas in the summer and fall it appears to be dependent on moisture. Soil gas samples were also collected during the spring from three sites in the Kyle Canyon area in southern Nevada to determine the variation of soil CO2 levels with changes in elevation and vegetation. Soil CO2 values increased from 0.04 to 0.24 volume percent with increasing elevation. The increased elevation is associated with increasing precipitation, greater vegetation increasing precipitation, greater vegetation density, and decreasing temperature. The CO2 values at the mid-elevation of 1400 m in Kyle Canyon were similar to CO2 values at Yucca Wash at 1266 m in elevation for the spring of 1986. C1 US GEOL SURVEY,MENLO PK,CA 94025. NR 16 TC 13 Z9 15 U1 0 U2 7 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0038-075X J9 SOIL SCI JI Soil Sci. PD JUN PY 1991 VL 151 IS 6 BP 417 EP 429 DI 10.1097/00010694-199106000-00003 PG 13 WC Soil Science SC Agriculture GA FV097 UT WOS:A1991FV09700003 ER PT J AU HOWE, WH KNOPF, FL AF HOWE, WH KNOPF, FL TI ON THE IMMINENT DECLINE OF RIO-GRANDE COTTONWOODS IN CENTRAL NEW-MEXICO SO SOUTHWESTERN NATURALIST LA English DT Article AB Increment cores from 144 Fremont cottonwoods (Populus fremontii var. wislizeni) were taken at three riparian woodland sites along the Rio Grande in New Mexico. Trees at two study sites averaged 38.8 and 43.2 years old. All trees fewer than 26 years old at those sites were root suckers from older trees whose primary trunks had decayed. The third site, one of few known locations where young trees are present, had 75% of the trees between 5 and 25 years old. Cottonwood recruitment generally (but not always) could be associated with years of overbank flooding. The combination of a paucity of cottonwood regeneration over the last 30 years, the rapid colonization during this century of Russian-olive (Elaeagnus angustifolia) and salt cedar (Tamarix chinensis) into the valley, and current river channel management practices suggests that the Rio Grande riparian woodland will become dominated by the exotic shrubs over the next 50 to 100 years. To assure the continued survival of the cottonwood riparian community along the Rio Grande, resource managers need to implement strategies to enhance cottonwood regeneration and survival and to control the spread of exotics. RP HOWE, WH (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,4512 MCMURRY AVE,FT COLLINS,CO 80525, USA. NR 0 TC 133 Z9 140 U1 3 U2 35 PU SOUTHWESTERN ASSN NATURALISTS PI SAN MARCOS PA SOUTHWEST TEXAS STATE UNIV, DEPT BIOLOGY, 601 UNIVERSITY DR, SAN MARCOS, TX 78666 SN 0038-4909 J9 SOUTHWEST NAT JI Southw. Natural. PD JUN PY 1991 VL 36 IS 2 BP 218 EP 224 DI 10.2307/3671924 PG 7 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA FW788 UT WOS:A1991FW78800010 ER PT J AU BENSON, SM WHITE, AF HALFMAN, S FLEXSER, S ALAVI, M AF BENSON, SM WHITE, AF HALFMAN, S FLEXSER, S ALAVI, M TI GROUNDWATER CONTAMINATION AT THE KESTERSON RESERVOIR, CALIFORNIA .1. HYDROGEOLOGIC SETTING AND CONSERVATIVE SOLUTE TRANSPORT SO WATER RESOURCES RESEARCH LA English DT Article ID SAN-JOAQUIN VALLEY; SELENIUM AB Shallow groundwater under Kesterson Reservoir, Merced County, California, was contaminated over a period of 6 years while the reservior was used for disposal of brackish subsurface agricultural drainage water from farmlands in the San Joaquin Valley. Drainage water contained an average of 10,000 mg/L total dissolved solids (TDS), high concentrations of selenium (300-mu-g/L), nitrate (37 mg/L as nitrogen), boron (15 mg/L), and lesser amounts of mercury, chromium, and molybdenum. Infiltration and lateral migration of this water created a 20-m-deep plume of high-TDS, boron-rich water covering an area of about 5 km2. Transport of selenium and nitrate was inhibited by biogeochemical reactions in the pond bottom sediments, so that migration of these two constituents into the aquifer was limited. This paper focuses on physical parameters affecting seepage and lateral migration of nonreactive solutes and on hydrogeological factors associated with selenium break-through into the shallow aquifer. An accompanying paper describes biogeochemical processes that limit nitrate and selenium migration (White et al., this issue). The regional hydrogeologic system at Kesterson Reservoir is dominated by the presence of four lithostratigraphic units. These are, in order of increasing depth, a fine-grained surfical layer extending to depths of as much as 8 m, a semiconfined sandy aquifer extending to 60 m, a widespread lacustrine clay confining layer, and a confined sandy aquifer. Within each of these units, order of magnitude variations in the hydrologic properties of the sediments occur ubiquitously over lateral distances of tens of meters and vertical distances of a fraction of a meter. Seepage rates from the ponds into the underlying aquifer are dominated by local hydrogeologic properties and thickness of the fine-grained surface layer. Selenium migrated into the aquifer in an area where the fine-grained surface layer was thin or absent. Once in the aquifer, local rates of migration are controlled by the small-scale structure and hydrogeologic properties of the sediments. The aquifer is composed of a heterogeneous mixture of sands, silts, and clays. Individual sand beds, which average about 0.3 m thick, do not appear to extend over lateral distances of more than 30 m. The large range of velocities combined with a limited lateral extent of individual layers are expected to create a broadly dispersed plume of solutes migrating downgradient from Kesterson. A noninvasive electromagnetic survey of electrical conductivity distributions in the shallow aquifer appears to confirm this conceptual model for transport in the shallow aquifer. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP BENSON, SM (reprint author), UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720, USA. NR 34 TC 24 Z9 24 U1 1 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JUN PY 1991 VL 27 IS 6 BP 1071 EP 1084 DI 10.1029/91WR00265 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FP651 UT WOS:A1991FP65100011 ER PT J AU NAFTZ, DL RICE, JA RANVILLE, JR AF NAFTZ, DL RICE, JA RANVILLE, JR TI GLACIAL ICE COMPOSITION - A POTENTIAL LONG-TERM RECORD OF THE CHEMISTRY OF ATMOSPHERIC DEPOSITION, WIND RIVER RANGE, WYOMING SO WATER RESOURCES RESEARCH LA English DT Article ID SULFUR-DIOXIDE EMISSIONS; WESTERN UNITED-STATES; ACID DEPOSITION; SNOW; POLLUTION; SULFATE; CORES AB During a reconnaissance study, ice samples were collected from Knife Point glacier to determine if glaciers in the Wind River Range could provide a long-term record of the chemical composition of wet deposition. Eight annual ice layers comprising the years 1980-1987 were identified. The concentration of calcium, chloride, and sulfate in the annual-weighted wet deposition samples collected at the National Atmospheric Deposition Program (NADP) station near Pinedale, Wyoming, showed a significant, positive correlation to the concentration of the same major ions in composite samples from the annual ice layers. Results of the study imply that continuous ice cores reaching to the deeper parts of glaciers in the Wind River Range could provide long-term records of the chemical composition of wet deposition. C1 US GEOL SURVEY,DENVER,CO 80002. S DAKOTA STATE UNIV,DEPT CHEM,BROOKINGS,SD 57007. RP NAFTZ, DL (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,2617 E LINCOLNWAY,SUITE B,CHEYENNE,WY 82001, USA. RI Ranville, James/H-1428-2011 NR 24 TC 4 Z9 4 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JUN PY 1991 VL 27 IS 6 BP 1231 EP 1238 DI 10.1029/91WR00687 PG 8 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FP651 UT WOS:A1991FP65100024 ER PT J AU NIMMO, JR MELLO, KA AF NIMMO, JR MELLO, KA TI CENTRIFUGAL TECHNIQUES FOR MEASURING SATURATED HYDRAULIC CONDUCTIVITY SO WATER RESOURCES RESEARCH LA English DT Article ID SOIL; FLOW AB Centrifugal force is an alternative to large pressure gradients for the measurement of low values of saturated hydraulic conductivity (K(sat)). With a head of water above a porous medium in a centrifuge bucket, both constant-head and falling-head measurements are practical at forces up to at least 1800 times normal gravity. Darcy's law applied to the known centrifugal potential leads to simple formulas for K(sat) that are analogous to those used in the standard gravity-driven constant- and falling-head methods. Both centrifugal methods were tested on several fine-textured samples of soil and ceramic with K(sat) between about 10(-10) and 10(-9) m/s. The results were compared to falling-head gravity measurements. The comparison shows most measurements agreeing to within 20% for a given sample, much of the variation probably resulting from run-to-run changes in sample structure. The falling-head centrifuge method proved to be especially simple in design and operation and was more accurate than the constant-head method. With modified apparatus, K(sat) measurements less than 10(-10) m/s should be attainable. RP NIMMO, JR (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,345 MIDDLEFIELD RD,MS 421,MENLO PK,CA 94025, USA. NR 11 TC 19 Z9 21 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JUN PY 1991 VL 27 IS 6 BP 1263 EP 1269 DI 10.1029/91WR00367 PG 7 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FP651 UT WOS:A1991FP65100027 ER PT J AU ANTHONY, RM FLINT, PL SEDINGER, JS AF ANTHONY, RM FLINT, PL SEDINGER, JS TI ARCTIC FOX REMOVAL IMPROVES NEST SUCCESS OF BLACK BRANT SO WILDLIFE SOCIETY BULLETIN LA English DT Article ID PREDATION; GEESE C1 US FISH & WILDLIFE SERV,ALASKA FISH & WILDLIFE RES CTR,ANCHORAGE,AK 99503. UNIV ALASKA,DEPT BIOL & WILDLIFE,FAIRBANKS,AK 99775. UNIV ALASKA,INST ARCTIC BIOL,FAIRBANKS,AK 99775. OI Flint, Paul/0000-0002-8758-6993 NR 25 TC 47 Z9 50 U1 2 U2 10 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD SUM PY 1991 VL 19 IS 2 BP 176 EP 184 PG 9 WC Biodiversity Conservation SC Biodiversity & Conservation GA FU987 UT WOS:A1991FU98700007 ER PT J AU BILDSTEIN, KL BANCROFT, GT DUGAN, PJ GORDON, DH ERWIN, RM NOL, E PAYNE, LX SENNER, SE AF BILDSTEIN, KL BANCROFT, GT DUGAN, PJ GORDON, DH ERWIN, RM NOL, E PAYNE, LX SENNER, SE TI APPROACHES TO THE CONSERVATION OF COASTAL WETLANDS IN THE WESTERN-HEMISPHERE SO WILSON BULLETIN LA English DT Article ID NEST-SITE SELECTION; WOOD STORK POPULATION; LEAST TERNS; AMERICAN OYSTERCATCHER; LAUGHING GULLS; UNITED-STATES; WHITE IBISES; NEW-JERSEY; COLONY; ABANDONMENT AB Coastal wetlands rank among the most productive and ecologically valuable natural ecosystems on Earth. Unfortunately, they are also some of the most disturbed. Because they are productive and can serve as transportation arteries, coastal wetlands have long attracted human settlement. More than half of the U.S. population currently lives within 80 km of its coasts, and one estimate places 70% of all humanity in the coastal zone. Human impacts to coastal wetlands include physical alteration of hydrological processes; the introduction of toxic materials, nutrients, heat, and exotic species; and the unsustainable harvest of native species. Between 1950 and 1970, coastal wetland losses in the U.S. averaged 8100 ha/year. In Central and South America, development pressures along the coastal zone rank among the most serious natural resource problems in the region. Here, we (1) briefly describe coastal wetland avifauna, (2) discuss the threat of global warming on coastal wetlands, (3) use several Western Hemisphere wetlands as site-specific examples of development pressures facing these habitats, and (4) provide synopses of non-governmental and governmental approaches to wetland conservation. Overall, we provide a socio-economic context for conservation of coastal wetlands in the wetlands in the Western Hemisphere. We suggest that efforts aimed at conserving sites of particular importance for their biological diversity should be pursued within a framework of wise use that addresses the broader issues of human population growth and economic development. C1 UNIV S CAROLINA,BELLE W BARUCH INST MARINE BIOL & COASTAL RES,COLUMBIA,SC 29208. TRENT UNIV,DEPT BIOL,PETERBOROUGH K9J 7B8,ONTARIO,CANADA. NATL AUDUBON SOC,DEPT RES,TAVERNIER,FL 33070. INT UNION CONSERVAT NAT WETLANDS PROGRAMME,CH-1196 GLAND,SWITZERLAND. INST WETLAND & WATERFOWL RES,GEORGETOWN,SC 29440. US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. MANOMET BIRD OBSERV,WESTERN HEMISPHERE SHOREBIRD RESERVE NETWORK,MANOMET,MA 02345. INT COUNCIL BIRD PRESERVAT INC,US SECT,ANCHORAGE,AK 99510. RP BILDSTEIN, KL (reprint author), WINTHROP COLL,DEPT BIOL,ROCK HILL,SC 29733, USA. NR 106 TC 54 Z9 55 U1 3 U2 20 PU WILSON ORNITHOLOGICAL SOC PI ANN ARBOR PA MUSEUM OF ZOOLOGY UNIV MICHIGAN, ANN ARBOR, MI 48109 SN 0043-5643 J9 WILSON BULL JI Wilson Bull. PD JUN PY 1991 VL 103 IS 2 BP 218 EP 254 PG 37 WC Ornithology SC Zoology GA FP905 UT WOS:A1991FP90500005 ER PT J AU GESSAMAN, JA FULLER, MR PEKINS, PJ DUKE, GE AF GESSAMAN, JA FULLER, MR PEKINS, PJ DUKE, GE TI RESTING METABOLIC-RATE OF GOLDEN EAGLES, BALD EAGLES, AND BARRED OWLS WITH A TRACKING TRANSMITTER OR AN EQUIVALENT LOAD SO WILSON BULLETIN LA English DT Note ID ECOLOGICAL ENERGETICS C1 UTAH STATE UNIV,CTR ECOL,LOGAN,UT 84322. US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. UNIV NEW HAMPSHIRE,DEPT FOREST RESOURCES,DURHAM,NH 03824. UNIV MINNESOTA,DEPT VET BIOL,ST PAUL,MN 55108. RP GESSAMAN, JA (reprint author), UTAH STATE UNIV,DEPT BIOL,LOGAN,UT 84322, USA. NR 8 TC 12 Z9 12 U1 1 U2 5 PU WILSON ORNITHOLOGICAL SOC PI ANN ARBOR PA MUSEUM OF ZOOLOGY UNIV MICHIGAN, ANN ARBOR, MI 48109 SN 0043-5643 J9 WILSON BULL JI Wilson Bull. PD JUN PY 1991 VL 103 IS 2 BP 261 EP 265 PG 5 WC Ornithology SC Zoology GA FP905 UT WOS:A1991FP90500007 ER PT J AU GERLACH, T AF GERLACH, T TI VOLCANOLOGY - ETNAS GREENHOUSE PUMP SO NATURE LA English DT Editorial Material ID KILAUEA VOLCANO; CYCLE RP GERLACH, T (reprint author), US GEOL SURVEY,CASCADES VOLCANO OBSERV,5400 MACARTHUR BLVD,VANCOUVER,WA 98661, USA. NR 10 TC 21 Z9 22 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD MAY 30 PY 1991 VL 351 IS 6325 BP 352 EP 353 DI 10.1038/351352a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FN856 UT WOS:A1991FN85600026 ER PT J AU LOCKWOOD, JP SCHUSTER, RL AF LOCKWOOD, JP SCHUSTER, RL TI LAKE NYOS DAM THREAT SO NATURE LA English DT Letter C1 US GEOL SURVEY,GEOL RISK ASSESSMENT BRANCH,DENVER,CO 80225. RP LOCKWOOD, JP (reprint author), US GEOL SURVEY,HAWAIIAN VOLCANO OBSERV,HAWAII NATL PK,HI 96718, USA. NR 4 TC 2 Z9 2 U1 0 U2 2 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD MAY 16 PY 1991 VL 351 IS 6323 BP 195 EP 196 DI 10.1038/351195b0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FL990 UT WOS:A1991FL99000039 ER PT J AU CARSON, B HOLMES, ML UMSTATTD, K STRASSER, JC JOHNSON, HP AF CARSON, B HOLMES, ML UMSTATTD, K STRASSER, JC JOHNSON, HP TI FLUID EXPULSION FROM THE CASCADIA ACCRETIONARY PRISM - EVIDENCE FROM POROSITY DISTRIBUTION, DIRECT MEASUREMENTS, AND GLORIA IMAGERY SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article ID SUBDUCTION ZONE; OREGON; WASHINGTON; CARBONATES; SEDIMENTS; MARGIN; FLOW AB Fluid expulsion from the Cascadia accretionary prism off Oregon results from porosity reduction by compaction, and by cementation as methane-rich pore waters precipitate diagenetic carbonate deposits near the sediment-water interface. Porosity changes suggest that dewatering begins 5-6 km west of the base of the slope, in a proto-deformation zone. GLORIA imagery of surficial carbonate deposits confirms that fluid is actively expelled from this zone; there is no such evidence further west in Cascadia Basin. Within the uncertainties of the data, porosities do not decrease landward beneath the prism. This pattern is consistent with imbricate thrust faulting on the slope which provides the vertical load to induce compactive dewatering, and may physically import as much as 50% of the total fluid volume in the section. A simple vertical compaction model suggests that significant pore water volumes have been expelled from the lower slope, but at flux rates (10(-11)-10(-12)m3m-2s-1) which are orders of magnitude less than those measured at individual vent sites (10(-6)m3m-2s-1). Faulting clearly controls some fluid expulsion, but GLORIA data suggest that repeated local discharge, cementation, and abandonment lead to dispersed accumulations of diagenetic carbonate. C1 UNIV WASHINGTON,SCH OCEANOG,US GEOL SURVEY,SEATTLE,WA 98195. CARLETON COLL,DEPT GEOL,NORTHFIELD,MN 55057. RP CARSON, B (reprint author), LEHIGH UNIV,DEPT GEOL SCI,BETHLEHEM,PA 18015, USA. NR 24 TC 17 Z9 17 U1 1 U2 3 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON, ENGLAND SW1Y 5AG J9 PHILOS T ROY SOC A JI Philos. Trans. R. Soc. Lond. Ser. A-Math. Phys. Eng. Sci. PD MAY 15 PY 1991 VL 335 IS 1638 BP 331 EP 340 DI 10.1098/rsta.1991.0049 PG 10 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FN509 UT WOS:A1991FN50900007 ER PT J AU HAUKSSON, E JONES, LM AF HAUKSSON, E JONES, LM TI THE 1988 AND 1990 UPLAND EARTHQUAKES - LEFT-LATERAL FAULTING ADJACENT TO THE CENTRAL TRANSVERSE RANGES SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID SOUTHERN-CALIFORNIA; SEQUENCE; STRESS AB Two earthquakes (M(L) = 4.6 and M(L) = 5.2) occurred at almost the same location in Upland, southern California, in June 1988 and February 1990 and had similar strike-slip focal mechanisms with left-lateral motion on a northeast striking plane. The focal mechanisms and aftershock locations showed that the causative fault was the San Jose fault, an 18-km-long concealed fault that splays west-southwest from the frontal fault of the central Transverse Ranges. Left-lateral strike-slip faults adjacent to the frontal faults may play an important role in the deformation of the Transverse Ranges and the Los Angeles basin as suggested by these Upland earthquakes, the left-lateral strike-slip 1988 M(L) = 4.9) Pasadena earthquake on the Raymond fault, 30 km to the west of Upland, and scattered background seismicity along other active left-lateral faults. These faults may transfer slip away from part of the frontal fault toward the south. Alternatively, these faults could represent secondary faulting related to the termination of the northwest striking right-lateral strike-slip faults to the south of the range front. The 1988 and 1990 Upland earthquakes ruptured abutting or possibly overlapping segments of the San Jose fault. The edges of the overlapping aftershock zones, which are sharply defined, together with background seismicity, outline a 14-km-long aseismic segment of the San Jose fault. The 1988 mainshock originated at 9.5 km depth and caused aftershocks between 5 and 12 km. In contrast, the 1990 mainshock focus occurred at the top of its aftershock zone, at 5 km, and caused aftershocks down to 13 km depth. These deep aftershocks tapered off within 2 weeks. The rate of occurrence of aftershocks in magnitude-time space was the same for both sequences. The state of stress reflected in the focal mechanisms of the aftershocks is identical to that determined from background activity and did not change with time during the aftershock sequence. The constant stress state suggests that the 1988 and 1990 events did not completely release all the stored slip on that segment of the fault. The presence of 14 km of unbroken fault, the abrupt temporal termination of deep aftershocks, and the constant stress state all suggest that a future moderate-sized earthquake (M(L) = 6.0-6.5) on the San Jose fault is possible with a rupture length of at least 14 km and possibly 18 km. C1 US GEOL SURVEY, PASADENA, CA 91106 USA. RP CALTECH, SEISMOL LAB, DIV GEOL & PLANETARY SCI, 252-21, PASADENA, CA 91125 USA. OI Hauksson, Egill/0000-0002-6834-5051 NR 33 TC 27 Z9 27 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAY 10 PY 1991 VL 96 IS B5 BP 8143 EP 8165 DI 10.1029/91JB00481 PG 23 WC Geosciences, Multidisciplinary SC Geology GA FL388 UT WOS:A1991FL38800013 ER PT J AU LISOWSKI, M SAVAGE, JC PRESCOTT, WH AF LISOWSKI, M SAVAGE, JC PRESCOTT, WH TI THE VELOCITY-FIELD ALONG THE SAN-ANDREAS FAULT IN CENTRAL AND SOUTHERN CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID STRIKE-SLIP FAULT; BASE-LINE INTERFEROMETRY; CRUSTAL DEFORMATION; STRAIN ACCUMULATION; GEODETIC MEASUREMENT; TRANSVERSE RANGES; EARTHQUAKE CYCLES; PLATE MOTIONS; UNITED-STATES; ZONE AB The velocity field within a 100-km-broad zone centered on the San Andreas fault between the Mexican border and San Francisco Bay has been inferred from repeated surveys of trilateration networks in the 1973-1989 interval. The velocity field has the appearance of a shear flow that remains parallel to the local strike of the fault even through such major deflections as the big bend of the San Andreas fault in the Transverse Ranges of southern California. Across-strike profiles of the fault-parallel component of velocity exhibit the expected sigmoidal shape, whereas across-strike profiles of the fault-normal component of velocity are flat and featureless. No significant convergence upon the fault is observed even along the big bend sector of the fault. Simple dislocation models can explain most of the features of the observed velocity field, but those explanations are not unique. About 35 mm/yr of relative plate motion is accounted for within the span of the trilateration networks. Geologic studies indicate that the secular slip rate on the San Andreas fault is about 35 mm/yr. The agreement between these two estimates implies that most of the strain accumulation is elastic and will be recovered in subsequent earthquakes. The relative motion observed across the San Andreas fault (35 mm/yr) plus that observed across the Eastern California shear zone (8 mm/yr) accounts for most (43 mm/yr) of the observed North America-Pacific relative plate motion (47 mm/yr). RP LISOWSKI, M (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS-977,MENLO PK,CA 94025, USA. NR 57 TC 203 Z9 203 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAY 10 PY 1991 VL 96 IS B5 BP 8369 EP 8389 DI 10.1029/91JB00199 PG 21 WC Geosciences, Multidisciplinary SC Geology GA FL388 UT WOS:A1991FL38800026 ER PT J AU RHODES, HA HUBERT, WA AF RHODES, HA HUBERT, WA TI SUBMERGED UNDERCUT BANKS AS MACROINVERTEBRATE HABITAT IN A SUB-ALPINE MEADOW STREAM SO HYDROBIOLOGIA LA English DT Article DE SUB-ALPINE; STREAM; AQUATIC INSECTS; MACROINVERTEBRATES; BENTHOS; SUBMERGED UNDERCUT BANKS ID INSECTS; TROUT; COLORADO; FAUNA AB We compared macroinvertebrate samples from submerged undercut banks with samples from rifles and pools in a low-gradient-meadow reach of a small stream on the Snowy Range, southeastern Wyoming, from July to September 1985. Macroinvertebrates collected from submerged undercut banks were similar to those collected from riffles and pools, but densities varied among the three habitat types. In July Ephemeroptera, Plecoptera, Trichoptera, Coleoptera, and Diptera, as well as Hydracarina, were all substantially more numerous in samples from undercut banks than from riffles or pools. By contrast in September little difference was observed in the abundance of macroinvertebrates in samples from submerged undercut banks, riffles and pools. While forming only 8.5% of the area of aquatic habitat within the study reach submerged undercut banks were estimated to contain 44% of the aquatic insects in July and 30% in August. Further, submerged undercut banks are macroinvertebrate habitat in this subalpine meadow stream, contributing to overall macroinvertebrate abundance and probably an additional food source for trout. RP RHODES, HA (reprint author), UNIV WYOMING,US FISH & WILDLIFE SERV,WYOMING FISH & WILDLIFE RES UNIT,LARAMIE,WY 82071, USA. NR 24 TC 10 Z9 10 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD MAY 3 PY 1991 VL 213 IS 2 BP 149 EP 153 DI 10.1007/BF00015001 PG 5 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA FP810 UT WOS:A1991FP81000008 ER PT J AU MILLER, JJ LEE, MW VONHUENE, R AF MILLER, JJ LEE, MW VONHUENE, R TI AN ANALYSIS OF A SEISMIC-REFLECTION FROM THE BASE OF A GAS HYDRATE ZONE, OFFSHORE PERU SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Article ID SEA; DIAGENESIS; HORIZONS; MEXICO; TRENCH; GULF; OMAN AB Seismic reflection data recorded near ODP Site 688, offshore Peru, exhibit a persistent bottom-simulating reflector (BSR) from a depth corresponding to the theoretical base of the gas hydrate stability field. Although gas hydrate has been recovered in cores from scientific drilling in both the Pacific and the Atlantic, drilling in areas exhibiting a BSR has usually been avoided because of the perceived risk of releasing free gas trapped beneath the hydrated sediments. To carry out a quantitative analysis of the BSR, the seismic data were reprocessed using signature deconvolution and true amplitude recovery techniques. Synthetic seismograms that were created using acoustic parameters extracted from the seismic data and physical properties from Site 688 borehole measurements were compared to the observed seismic data to estimate the thickness of the free-gas zone. Results indicate the BSR is discontinuous laterally. Where the BSR is of high amplitude, free gas in a zone 5.5-17 m thick beneath the hydrated sediments provides the observed waveform; where the BSR amplitude is low, the free-gas zone is much thinner than 5.5 m or is entirely absent. C1 GEOMAR,MARINE GEOSCI RES CTR,W-2300 KIEL 14,GERMANY. RP MILLER, JJ (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 960,BOX 25046,DENVER,CO 80225, USA. NR 44 TC 98 Z9 112 U1 1 U2 4 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAY PY 1991 VL 75 IS 5 BP 910 EP 924 PG 15 WC Geosciences, Multidisciplinary SC Geology GA FJ402 UT WOS:A1991FJ40200004 ER PT J AU TOULMIN, P BARTON, PB WIGGINS, LB AF TOULMIN, P BARTON, PB WIGGINS, LB TI COMMENTARY ON THE SPHALERITE GEOBAROMETER SO AMERICAN MINERALOGIST LA English DT Note ID HEXAGONAL PYRRHOTITE GEOBAROMETER; BASE-METAL DEPOSITS; ZN-S SYSTEM; EXPERIMENTAL CALIBRATION; METAMORPHIC PRESSURE; CRYSTAL-STRUCTURE; BROKEN-HILL; ORE; COSMOBAROMETER; REFINEMENT AB The FeS content of sphalerite in assemblages with pyrite and pyrrhotite has been widely used and widely criticized as a geobarometer. The commonly accepted form of the geobarometer is based on the composition of sphalerite being independent of temperature below about 550-degrees-C at all pressures up to at least 10 kbar, but strong thermodynamic arguments require a significant temperature dependence in this region. Most minor components have a negligible effect on the relevant equilibria, but the effect of CuS is somewhat more significant. Molar and partial molar volumes for binary (ZnS-FeS) and ternary (ZnS-FeS-CuS) sphalerite solutions are presented; the ternary data are consistent with charge transfer between Cu and Fe. Difficulties in the application of the sphalerite geobarometer also arise from failure to consider adequately the paragenetic implications of textural relations among the minerals involved. An example from Ducktown, Tennessee, demonstrates the importance of nonequilibrium features and their interpretive value. Based on commonly occurring minerals of simple chemistry, sound theory, favorable kinetic factors, and a considerable body of experimental data, the sphalerite geobarometer requires only careful application and resolution of the remaining conflict between theory and experiment to provide an extraordinarily useful tool in the interpretation of geologic processes over time. RP TOULMIN, P (reprint author), US GEOL SURVEY,959 NATL CTR,RESTON,VA 22092, USA. NR 71 TC 34 Z9 34 U1 0 U2 1 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1130 17TH ST NW SUITE 330, WASHINGTON, DC 20036 SN 0003-004X J9 AM MINERAL JI Am. Miner. PD MAY-JUN PY 1991 VL 76 IS 5-6 BP 1038 EP 1051 PG 14 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA FX234 UT WOS:A1991FX23400028 ER PT J AU COPLEN, TB WILDMAN, JD CHEN, J AF COPLEN, TB WILDMAN, JD CHEN, J TI IMPROVEMENTS IN THE GASEOUS-HYDROGEN WATER EQUILIBRATION TECHNIQUE FOR HYDROGEN ISOTOPE RATIO ANALYSIS SO ANALYTICAL CHEMISTRY LA English DT Article AB Improved precision in the H-2-H2O equilibration method for delta-D analysis has been achieved in an automated system. Reduction in 1-sigma standard deviation of a single mass-spectrometer analysis to 1.3 parts-per-thousand is achieved by (1) bonding catalyst to glass rods and assigning use to specific equilibration chambers to monitor performance of catalyst, (2) improving the apparatus design, and (3) reducing the H-3+ contribution of the mass-spectrometer ion source. For replicate analysis of a water sample, the standard deviation improved to 0.8-parts-per-thousand. H2S-bearing samples and samples as small as 0.1 mL can be analyzed routinely with this method. RP COPLEN, TB (reprint author), US GEOL SURVEY,431 NATL CTR,RESTON,VA 22092, USA. NR 8 TC 144 Z9 145 U1 3 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 1 PY 1991 VL 63 IS 9 BP 910 EP 912 DI 10.1021/ac00009a014 PG 3 WC Chemistry, Analytical SC Chemistry GA FJ318 UT WOS:A1991FJ31800016 ER PT J AU BATTS, WN LANDOLT, ML WINTON, JR AF BATTS, WN LANDOLT, ML WINTON, JR TI INACTIVATION OF INFECTIOUS HEMATOPOIETIC NECROSIS VIRUS BY LOW-LEVELS OF IODINE SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SALMON ONCORHYNCHUS-NERKA; SOCKEYE SALMON; 2 IODOPHORS; INCUBATION BOXES; FISH; WATER; EGGS; TRANSMISSION; FILTRATION; MORTALITY AB The fish rhabdovirus infectious hematopoietic necrosis virus (IHNV) was rapidly inactivated by extremely low concentrations of iodine in water. A 99.9% virus reduction was obtained in 7.5 s when virus (10(5) PFU/mI) and iodine (0.1 mg/liter, final concentration) were combined in distilled-deionized or hatchery water. Iodine efficacy decreased at pHs greater than 7.5 or when proteinaceous material was added to the water. Bovine serum albumin blocked iodine inactivation of the virus more effectively than did equal concentrations of fetal bovine serum or river sediment. Sodium thiosulfate effectively neutralized free iodine. Powder, iodophor, and crystalline iodine solutions inactivated IHNV equally. Iodine rapidly inactivated IHNV isolates representing each of the five electropherotypes. Under the conditions used in this study, inactivation was not affected by temperature, salinity, or water hardness. When Dworshak National Fish Hatchery water was continuously treated to provide a free iodine concentration of 0.14 mg/liter, a 7.5-s exposure to iodine was sufficient to inactivate 99.9% of the IHNV. Iodine added to water that contained IHNV prevented infection of rainbow trout (Oncorhynchus mykiss) fry. These results suggest that the waterborne route of IHNV transmission can be blocked by adding low iodine concentrations to the water supplies of hatcheries. C1 UNIV WASHINGTON,SCH FISHERIES,SEATTLE,WA 98195. RP BATTS, WN (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,BLDG 204,NAVAL STN,SEATTLE,WA 98115, USA. NR 33 TC 10 Z9 10 U1 1 U2 4 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD MAY PY 1991 VL 57 IS 5 BP 1379 EP 1385 PG 7 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA FK459 UT WOS:A1991FK45900016 PM 16348481 ER PT J AU LOWE, TP STENDELL, RC AF LOWE, TP STENDELL, RC TI EGGSHELL MODIFICATIONS IN CAPTIVE AMERICAN KESTRELS RESULTING FROM AROCLOR-1248 IN THE DIET SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID DDE AB American kestrels (Falco sparverius) were fed diets containing 3-mu-g/g Aroclor(R)1 1248 or control diets from mid-January until July. Eggs were removed from first clutches 2 to 4 days after laying ceased and shell thickness and shell dimensions were measured. Contents of the third egg of each clutch, the carcasses of all adults that received Aroclor(R) 1248 and of three males and three females that received the control diet were analyzed for DDE, Aroclors(R) 1248, 1254 and 1260, and dieldrin. Concentrations of PCBs, DDE and dieldrin were significantly higher (P < 0.03) in eggs and carcasses from treated adults than in controls. Shell thickness and shell thickness index of eggs from treated adults were reduced 5.0% (P < 0.0001) and 4.8% (P < 0.0001), respectively, from those of controls. C1 US FISH & WILDLIFE SERV,NATL ECOL CTR,FT COLLINS,CO 80525. RP LOWE, TP (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 21 TC 13 Z9 13 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD MAY PY 1991 VL 20 IS 4 BP 519 EP 522 PG 4 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FH939 UT WOS:A1991FH93900011 ER PT J AU GOCHFELD, M SALIVA, J LESSER, F SHUKLA, T BERTRAND, D BURGER, J AF GOCHFELD, M SALIVA, J LESSER, F SHUKLA, T BERTRAND, D BURGER, J TI EFFECTS OF COLOR ON CADMIUM AND LEAD LEVELS IN AVIAN CONTOUR FEATHERS SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID MERCURY LEVELS; MOLT AB The use of feathers has been proposed as a non-invasive tissue for biomonitoring metal levels in birds and their ecosystems. We examined cadmium and lead levels in black and white contour feathers from common (Sterna hirundo) and sooty (S. fuscata) terns, and black skimmers (Rynchops niger) to determine if there were significant differences in metal levels related to the melanin content of the feathers. There were no significant differences in metals in black versus white body feathers in any of the three species; correlations between metal residues from individual birds were low. C1 ENVIRONM & OCCUPAT HLTH SCI INST,PISCATAWAY,NJ 08854. RUTGERS STATE UNIV,BUR BIOL RES,PISCATAWAY,NJ 08855. US FISH & WILDLIFE SERV,BOQUERON,PR 00622. WETLANDS ASSOCIATES,PINE BEACH,NJ 08741. RP GOCHFELD, M (reprint author), UNIV MED & DENT NEW JERSEY,ROBERT WOOD JOHNSON MED SCH,PISCATAWAY,NJ 08854, USA. NR 21 TC 13 Z9 13 U1 1 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD MAY PY 1991 VL 20 IS 4 BP 523 EP 526 PG 4 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FH939 UT WOS:A1991FH93900012 ER PT J AU NOGUCHI, GE HESSELBERG, RJ AF NOGUCHI, GE HESSELBERG, RJ TI PARENTAL TRANSFER OF ORGANIC CONTAMINANTS TO YOUNG-OF-THE-YEAR SPOTTAIL SHINERS, NOTROPIS-HUDSONIUS SO BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID ACCUMULATION RP NOGUCHI, GE (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105, USA. NR 8 TC 5 Z9 5 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0007-4861 J9 B ENVIRON CONTAM TOX JI Bull. Environ. Contam. Toxicol. PD MAY PY 1991 VL 46 IS 5 BP 745 EP 750 PG 6 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA FE998 UT WOS:A1991FE99800017 PM 1903996 ER PT J AU BRANDT, SB MASON, DM PATRICK, EV ARGYLE, RL WELLS, L UNGER, PA STEWART, DJ AF BRANDT, SB MASON, DM PATRICK, EV ARGYLE, RL WELLS, L UNGER, PA STEWART, DJ TI ACOUSTIC MEASURES OF THE ABUNDANCE AND SIZE OF PELAGIC PLANKTIVORES IN LAKE-MICHIGAN SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID FISH TARGET STRENGTH; ECHO PEAK PDF; THERMAL HABITAT; ALOSA-PSEUDOHARENGUS; COMMUNITY STRUCTURE; INDIVIDUAL FISH; WATER-QUALITY; PREY; ALEWIVES; POPULATIONS AB Based on acoustic data taken at night and vertically stratified by bottom depth (3-110 m only), the total number (+/- 95% Cl) of pelagic fishes in Lake Michigan was 43.4 +/- 10.1 x 10(9) or 226.0 +/- 55.2 kt in spring (mean density 0.7-3.8 fish.m-2 or 1.6-12.8 g.m-2) and 115.8 +/- 18.3 x 10(9) or 313.2 +/- 74.3 kt in late summer, 1987 (mean density 1.1-7.9 fish.m-2 or 3.0-13.2 g.m-2); approximately 30% of this increase in numbers (35% of biomass) occurred within Green Bay. Abundance estimates from horizontally stratified (by water column depth) data were within 9-11% of vertically stratified estimates during spring but over 20% higher during summer. By extrapolation to all water depths, we estimated total pelagic biomass as 274.6 kt for spring and 410.8 kt for summer. During both seasons, smaller fishes were nearer to the surface and nearer shore than larger individuals, and acoustic measures of size approximated the sizes of fishes caught in trawls. Bioenergetic model simulations suggest that 60% of the available production of alewife (Alosa pseudoharengus) was either consumed by stocked salmonines (52.9%) or commercially harvested (7.1%) in 1987. Underwater acoustics proved a valuable tool for lakewide assessments of fish abundances in the Great Lakes. C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR GREAT LAKES,ANN ARBOR,MI 48105. INTERMED ORTHOPED INC,AUSTIN,TX 78752. SUNY COLL ENVIRONM SCI & FORESTRY,SYRACUSE,NY 13210. RP BRANDT, SB (reprint author), UNIV MARYLAND,CHESAPEAKE BIOL LAB,SOLOMONS,MD 20688, USA. NR 62 TC 89 Z9 92 U1 1 U2 15 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD MAY PY 1991 VL 48 IS 5 BP 894 EP 908 DI 10.1139/f91-106 PG 15 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA FP953 UT WOS:A1991FP95300019 ER PT J AU ROGERS, JB BURLEY, CC AF ROGERS, JB BURLEY, CC TI A SIGMOID MODEL TO PREDICT GASTRIC EVACUATION RATES OF SMALLMOUTH BASS (MICROPTERUS-DOLOMIEUI) FED JUVENILE SALMON SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID STIZOSTEDION-VITREUM-VITREUM; FOOD CONVERSION EFFICIENCY; FEEDING PERIODICITY; CONSUMPTION; DIGESTION AB Laboratory experiments were conducted to examine the effects of water temperature, predator size, prey size, and prey number on gastric evacuation of smallmouth bass (Micropterus dolomieui) fed juvenile salmon. The smallmouth bass were allowed to feed voluntarily after 24-48 h of starvation and stomachs were pumped at intervals of 1-4 h until 90% of the stomach contents were evacuated (E90). Evacuation approximated an S-shaped curve over time, and a sigmoid model was developed to predict evacuation at varying water temperatures, total meal weights, predator sizes, and prey number. The rate of evacuation increased with increasing water temperature, meal weight, or predator size. The E90 increased with larger meal weights but decreased with increasing temperature or predator size. E90 ranged between 4 and 95 h, depending upon conditions. E90 was slower than those estimated previously for another predator of salmon, the stomachless northern squawfish (Ptychocheilus oregonensis). C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,SEATTLE,WA. COLUMBIA RIVER FIELD STN,COOK,WA 98605. NR 25 TC 23 Z9 24 U1 0 U2 1 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD MAY PY 1991 VL 48 IS 5 BP 933 EP 937 DI 10.1139/f91-109 PG 5 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA FP953 UT WOS:A1991FP95300022 ER PT J AU BODKIN, JL JAMESON, RJ AF BODKIN, JL JAMESON, RJ TI PATTERNS OF SEABIRD AND MARINE MAMMAL CARCASS DEPOSITION ALONG THE CENTRAL CALIFORNIA COAST, 1980-1986 SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID EL-NINO; WAVES AB At monthly intervals from February 1980 through December 1986, a 14.5-km section of central California coastline was systematically surveyed for beach-cast carcasses of marine birds and mammals. Five hundred and fifty-four bird carcasses and 194 marine mammal carcasses were found. Common murres, western grebes, and Brandt's cormorants composed 45% of the bird total. California sea lions, sea otters, and harbor seals composed 90% of the mammal total. Several factors appeared to affect patterns of carcass deposition. The El Nino - Southern Oscillation (ENSO) of 1982-1983 was the dominant influence in terms of interannual variation in carcass deposition. During this ENSO, 56% of the seabirds and 48% of the marine mammals washed ashore. Patterns of intra-annual variation were species specific and were related to animal migration patterns, reproduction, and seasonal changes in weather. Nearshore currents and winds influenced the general area of carcass deposition, while beach substrate type and local patterns of sand deposition influenced the location of carcass deposition on a smaller spatial scale. Weekly surveys along a 1.1-km section of coastline indicated that 62% of bird carcasses and 41% of mammal carcasses remained on the beach less than 9 days. Cause of death was determined for only 8% of the carcasses. Oiling was the most common indication of cause of death in birds (6%). Neonates composed 8% of all mammal carcasses. C1 UNIV CALIF SANTA CRUZ,US FISH & WILDLIFE SERV,NATL ECOL RES CTR,SANTA CRUZ FIELD STN,SANTA CRUZ,CA 95064. US FISH & WILDLIFE SERV,NATL ECOL RES CTR,PIEDRAS BLANCAS FIELD STN,SAN SIMEON,CA 93452. NR 26 TC 22 Z9 25 U1 4 U2 7 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD MAY PY 1991 VL 69 IS 5 BP 1149 EP 1155 DI 10.1139/z91-163 PG 7 WC Zoology SC Zoology GA GB815 UT WOS:A1991GB81500002 ER PT J AU DEGANGE, AR DAY, RH AF DEGANGE, AR DAY, RH TI MORTALITY OF SEABIRDS IN THE JAPANESE LAND-BASED GILLNET FISHERY FOR SALMON SO CONDOR LA English DT Article DE NORTH PACIFIC OCEAN; SEABIRDS; DRIFT GILL NETS; HIGH-SEAS; ENTANGLEMENT; MORTALITY AB Mortality rates of seabirds in the Japanese land-based drift gillnet fishery for salmon were assessed from 413 gillnet sets made by Japanese research vessels in offshore areas used by the commercial fleet. Sixteen species of seabirds were recorded in nets. Shearwaters, primarily Short-tailed Shearwaters (Puffinus tenuirostris), and to a lesser extent Sooty Shearwaters (P. griseus), predominated in the catches, followed by lesser numbers of Tufted Puffins (Fratercula cirrhata) and Thick-billed Murres (Uria lomvia). Catch-rates of seabirds varied by oceanographic zone, with most being caught in oceanic waters north of the Subarctic Front. Approximately 151,000 seabirds were killed in the offshore component of the land-based fishery in 1977. Mortality was reduced to about 57,000 seabirds in 1987 because of a reduction in fishing effort. No estimates are available of seabird mortality in the nearshore component of the fishery. Mortality of seabirds in the land-based fishery is discussed with respect to other major drift gillnet fisheries in the North Pacific. C1 US FISH & WILDLIFE SERV,ALASKA FISH & WILDLIFE RES CTR,ANCHORAGE,AK 99503. UNIV ALASKA,INST MARINE SCI,FAIRBANKS,AK 99775. NR 26 TC 16 Z9 16 U1 0 U2 3 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD MAY PY 1991 VL 93 IS 2 BP 251 EP 258 DI 10.2307/1368940 PG 8 WC Ornithology SC Zoology GA FN966 UT WOS:A1991FN96600003 ER PT J AU LOKEMOEN, JT AF LOKEMOEN, JT TI BROOD PARASITISM AMONG WATERFOWL NESTING ON ISLANDS AND PENINSULAS IN NORTH-DAKOTA SO CONDOR LA English DT Article DE REDHEAD; AYTHYA-AMERICANA; BROOD PARASITISM; ISLANDS; NESTING; PENINSULAS; WATERFOWL ID REDHEADS; DUCKS AB During 1985 and 1986 I studied interspecific brood parasitism among seven species of waterfowl nesting on 36 islands and 24 peninsulas in central North Dakota. On islands, 40% of 178 nests were parasitized with an average of 4.3 parasitic eggs, and on peninsulas 2% of 275 nests were parasitized with an average of 2.2 parasitic eggs. Redheads (Aythya americana) were the primary parasite, adding eggs to 92% of all parasitized nests. Species nesting in open cover were parasitized at a higher rate than species nesting in dense cover. Nests with parasitic eggs had fewer host eggs and there was a negative association between the number of parasitic eggs and the success of host eggs. Parasitized nests had lower success, but additional parasitic eggs had no added influence on nest success. Interspecific brood parasitism had significant negative effects on dabbling ducks on islands but Lesser Scaup (Aythya affinis) were little affected. Even so, the number of young hatched per nest was much higher on islands because of the high loss of eggs to predators on the mainland. Parasitic eggs were deposited during the middle of the nesting season, but the peak of parasitic laying occurred before the peak of normal nesting. RP LOKEMOEN, JT (reprint author), US FISH & WILDLIFE SERV,NO PRAIRIE WILDLIFE RES CTR,ROUTE 1,BOX 96C,JAMESTOWN,ND 58401, USA. NR 22 TC 11 Z9 12 U1 0 U2 6 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD MAY PY 1991 VL 93 IS 2 BP 340 EP 345 DI 10.2307/1368949 PG 6 WC Ornithology SC Zoology GA FN966 UT WOS:A1991FN96600012 ER PT J AU HATCH, SA AF HATCH, SA TI EVIDENCE FOR COLOR PHASE EFFECTS ON THE BREEDING AND LIFE-HISTORY OF NORTHERN FULMARS SO CONDOR LA English DT Article DE NORTHERN FULMAR; FULMARUS-GLACIALIS; POLYMORPHISM; COLOR PHASES; BREEDING BIOLOGY; LIFE HISTORY ID GLACIALIS; SUCCESS; MATE AB About 15% of Northern Fulmars (Fulmarus glacialis) breeding on the Semidi Islands in 1979 had light-phase plumage; the remainder were dark. Fulmars of different plumage types mated indiscriminantly, but the lighter member of a mixed pair was more likely to be male than female. Pairs that included at least one light-phase member had lower breeding success than dark/dark pairs in one of six years. Constancy of breeding site use differed between light/dark and dark/dark pairs, suggesting dark birds skipped more breeding attempts or had lower over-winter survival than light birds. The apparent effect of breeding experience (assessed by site fidelity) on success also differed between pair types. The polymorphism on the Semidi Islands may result from light-phase fulmars immigrating from the Bering Sea, but there is also evidence to suggest it is maintained by balancing selection in a closed population. RP HATCH, SA (reprint author), US FISH & WILDLIFE SERV,ALASKA FISH & WILDLIFE RES CTR,1011 E TUDOR RD,ANCHORAGE,AK 99503, USA. NR 26 TC 12 Z9 12 U1 0 U2 0 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD MAY PY 1991 VL 93 IS 2 BP 409 EP 417 DI 10.2307/1368957 PG 9 WC Ornithology SC Zoology GA FN966 UT WOS:A1991FN96600020 ER PT J AU SCOTT, JM AF SCOTT, JM TI POPULATION ESTIMATES OF THE BLACK-CAPPED VIREO SO CONDOR LA English DT Note ID ABUNDANCE; PALILA C1 UNIV IDAHO,DEPT FISH & WILDLIFE RESOURCES,MOSCOW,ID 83843. RP SCOTT, JM (reprint author), UNIV IDAHO,US FISH & WILDLIFE SERV,IDAHO COOPERAT FISH & WILDLIFE RES UNIT,MOSCOW,ID 83843, USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU COOPER ORNITHOLOGICAL SOC PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0010-5422 J9 CONDOR JI Condor PD MAY PY 1991 VL 93 IS 2 BP 469 EP 472 DI 10.2307/1368972 PG 4 WC Ornithology SC Zoology GA FN966 UT WOS:A1991FN96600035 ER PT J AU VELDE, B DUBOIS, J MOORE, D TOUCHARD, G AF VELDE, B DUBOIS, J MOORE, D TOUCHARD, G TI FRACTAL PATTERNS OF FRACTURES IN GRANITES SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article ID STRIKE-SLIP FAULTS; SAN-ANDREAS FAULT; SIERRA-NEVADA; ABBOT QUADRANGLE; ROCK; CALIFORNIA AB Fractal measurements using the Cantor's dust method in a linear one-dimensional analysis mode were made on the fracture patterns revealed on two-dimensional, planar surfaces in four granites. This method allows one to conclude that: (1) The fracture systems seen on two-dimensional surfaces in granites are consistent with the part of fractal theory that predicts a repetition of patterns on different scales of observation, self similarity. Fractal analysis gives essentially the same values of D on the scale of kilometres, metres and centimetres (five orders of magnitude) using mapped, surface fracture patterns in a Sierra Nevada granite batholith (Mt. Abbot quadrangle, Calif.). (2) Fractures show the same fractal values at different depths in a given batholith. Mapped fractures (main stage ore veins) at three mining levels (over a 700 m depth interval) of the Boulder batholith, Butte, Mont. show the same fractal values although the fracture disposition appears to be different at different levels. (3) Different sets of fracture planes in a granite batholith, Central France, and in experimental deformation can have different fractal values. In these examples shear and tension modes have the same fractal values while compressional fractures follow a different fractal mode of failure. The composite fracture patterns are also fractal but with a different, median, fractal value compared to the individual values for the fracture plane sets. These observations indicate that the fractal method can possibly be used to distinguish fractures of different origins in a complex system. It is concluded that granites fracture in a fractal manner which can be followed at many scales. It appears that fracture planes of different origins can be characterized using linear linear fractal analysis. C1 INST PHYS GLOBE,OBSERV VOLCANOL,F-75252 PARIS,FRANCE. UNIV POITIERS,MECAN FLUIDES LAB,F-89022 POITIERS,FRANCE. US GEOL SURVEY,MENLO PK,CA 94025. RP VELDE, B (reprint author), ECOLE NORM SUPER,CNRS,UR 1316,DEPT GEOL,24 RUE LHOMOND,F-75231 PARIS 05,FRANCE. NR 25 TC 52 Z9 53 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD MAY PY 1991 VL 104 IS 1 BP 25 EP 35 DI 10.1016/0012-821X(91)90234-9 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FR287 UT WOS:A1991FR28700003 ER PT J AU GOMEZ, B MARRON, DC AF GOMEZ, B MARRON, DC TI NEOTECTONIC EFFECTS ON SINUOSITY AND CHANNEL MIGRATION, BELLE FOURCHE RIVER, WESTERN SOUTH-DAKOTA SO EARTH SURFACE PROCESSES AND LANDFORMS LA English DT Article DE MEANDERS; NEOTECTONICS; SINUOSITY ID UNITED-STATES AB Short-term instability in the behaviour of a small, meandering alluvial channel is identified from the relation between sinuosity and either floodplain slope or channel slope within 17 reaches along an 81-kilometre section of the Belle Fourche River in western South Dakota. In reaches 1 to 4 and 11 to 17 the channel is relatively stable and sinuosity varies inversely with channel slope. In reaches 5 to 10, sinuosity is positively related to floodplain slope. Sinuosity increases markedly in reaches 5, 6, and 7 (which are immediately downstream from a discontinuity in the long profile of the floodplain) in association with an increase in floodplain slope. Immediately upstream from the discontinuity, bankfull channel depth and sinuosity decrease and the area of the floodplain reworked by meander migration between 1939 and 1981 increases, in association with a decrease in floodplain slope. Channel behaviour in reaches 5 to 10 is best explained as a consequence of neotectonic activity, as indicated by changes in elevation recorded along geodetic survey lines that cross lineaments that may delimit the eastern boundary of the Black Hills uplift. Sinuosity acts as a barometer of the effects of neotectonic activity on alluvial channels. Initial indications of channel and floodplain instability due to neotectonic activity may be derived from evidence of anomalously active channel migration, as documented from photographic or topographic sources. C1 US GEOL SURVEY,INDIANAPOLIS,IN 46278. RP GOMEZ, B (reprint author), INDIANA STATE UNIV,DEPT GEOGR & GEOL,TERRE HAUTE,IN 47809, USA. NR 21 TC 24 Z9 26 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0197-9337 J9 EARTH SURF PROCESSES JI Earth Surf. Process. Landf. PD MAY PY 1991 VL 16 IS 3 BP 227 EP 235 DI 10.1002/esp.3290160304 PG 9 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA FJ194 UT WOS:A1991FJ19400003 ER PT J AU SKAGEN, SK KNIGHT, RL ORIANS, GH AF SKAGEN, SK KNIGHT, RL ORIANS, GH TI HUMAN DISTURBANCE OF AN AVIAN SCAVENGING GUILD SO ECOLOGICAL APPLICATIONS LA English DT Article DE AGGRESSION; AMERICAN CROWS; AVIAN SCAVENGERS; BALD EAGLES; FORAGING GUILD; GLAUCOUSWINGED GULLS; GUILD THEORY; HUMAN DISTURBANCE; NICHE SHIFTS; PACIFIC NORTHWEST; RECREATION; WILDLIFE MANAGEMENT ID WINTERING BALD EAGLES; INTERSPECIFIC COMPETITION; ENVIRONMENTAL-IMPACT; NICHE SHIFTS; TITS; COMMUNITIES; MANAGEMENT; RESPONSES; BEHAVIOR AB In order to investigate the effects of human activities on relationships within foraging guilds, we examined intraguild dynamics of eagles, crows, and gulls scavenging on spawned salmon in the Pacific Northwest. We examined several hypotheses that postulate the asymmetric foraging relationships of the three guild members and that reveal the influence of competition and facilitation in these relationships. Spatial and temporal patterns of resource use by the three primary guild members varied with the presence and absence of human activity at experimental feeding stations. At control (undisturbed) stations, eagles preferred to feed > 100 m from vegetative cover, whereas gulls fed < 50 m from cover. At experimental (disturbed) stations, eagles rarely fed, and feeding activity by gulls increased at both near and far stations. Crows often fed on alternate food sources in fields adjacent to the river, especially when salmon carcasses were scarce, whereas eagles and gulls rarely did so. We also examined if and how the behavior of single guild members changes in the presence or absence of other guild members. In the absence of eagles, gulls and crows preferred stations far from cover, numbers of both increased at feeding stations, birds were distributed nearer to carcasses, and they fed more. We emphasize that guild theory lends important insights to our understanding of the effects of human disturbance on wildlife communities. C1 COLORADO STATE UNIV,DEPT FISHERY & WILDLIFE BIOL,FT COLLINS,CO 80523. UNIV WASHINGTON,DEPT ZOOL,SEATTLE,WA 98195. UNIV WASHINGTON,INST ENVIRONM STUDIES,SEATTLE,WA 98195. RP SKAGEN, SK (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,FT COLLINS,CO 80525, USA. NR 45 TC 60 Z9 62 U1 3 U2 15 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 1051-0761 J9 ECOL APPL JI Ecol. Appl. PD MAY PY 1991 VL 1 IS 2 BP 215 EP 225 DI 10.2307/1941814 PG 11 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA FP618 UT WOS:A1991FP61800011 PM 27755665 ER PT J AU SIDLE, JG MAYNE, K MCPHILLIPS, EN AF SIDLE, JG MAYNE, K MCPHILLIPS, EN TI PROTECTING THE PIPING PLOVER UNDER SECTION-7 OF THE ENDANGERED SPECIES ACT SO ENVIRONMENTAL MANAGEMENT LA English DT Article DE ENDANGERED SPECIES ACT; PIPING PLOVER; INTERAGENCY CONSULTATION; BIOLOGICAL OPINION AB Section 7(a)(2) of the Endangered Species Act directs federal agencies to ensure that their actions do not jeopardize the continued existence of endangered and threatened species. The US Fish and Wildlife Service (USFWS) issues jeopardy or nonjeopardy biological opinions on proposed federal actions that affect endangered and threatened species. We summarize several biological opinions issued by the USFWS to protect the threatened piping plover (Charadrius melodus). These opinions address federal actions involving hundreds of piping plovers on the Missouri River system and a few piping plover pairs on short stretches of Atlantic coast beach. Some of these opinions are decisive, but most allow the proposed action to proceed conditional upon a lengthy set of reasonable and prudent alternatives to protect the piping plover. These conditions may prove difficult to track and will add to the workload of the USFWS. C1 US FISH & WILDLIFE SERV,WHITE MARSH,VA 23183. US FISH & WILDLIFE SERV,PIERRE,SD 57501. RP SIDLE, JG (reprint author), US FISH & WILDLIFE SERV,203 W 2ND ST,GRAND ISL,NE 68801, USA. NR 25 TC 4 Z9 4 U1 2 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0364-152X J9 ENVIRON MANAGE JI Environ. Manage. PD MAY-JUN PY 1991 VL 15 IS 3 BP 349 EP 356 DI 10.1007/BF02393881 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA FQ041 UT WOS:A1991FQ04100006 ER PT J AU BRANNON, JC PODOSEK, FA VIETS, JG LEACH, DL GOLDHABER, M ROWAN, EL AF BRANNON, JC PODOSEK, FA VIETS, JG LEACH, DL GOLDHABER, M ROWAN, EL TI STRONTIUM ISOTOPIC CONSTRAINTS ON THE ORIGIN OF ORE-FORMING FLUIDS OF THE VIBURNUM TREND, SOUTHEAST MISSOURI SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID VALLEY-TYPE DEPOSITS; LEAD-ZINC DEPOSITS; BONNETERRE FORMATION; BUICK MINE; SEA-WATER; SULFIDES; GALENA; MINERALIZATION; GEOLOGY; GEOCHEMISTRY AB We have measured Sr-87/Sr-86 and Rb and Sr concentrations in several minerals, primarily sulfides,spanning the paragenesis of hydrothermal mineralization in the Viburnum Trend in southeast Missouri. Separate measurements were made for fluid inclusions opened by crushing or thermal decrepitation and for the solids. For comparison, measurements were also made on samples of probable local aquifers, the Bonneterre Formation and the Lamotte Sandstone. For some of the samples, concentrations of K, Ca, Cl, Na, and Mg are also reported. In several cases Sr-87/Sr-86 ratios are different (higher) in the solids than in the fluid inclusions. We have investigated the possibility that either type of sample gives spurious results, e.g., that the fluid inclusions are secondary or contaminated by host dolomite, or that Sr in the solids reflects a detrital rather than an authigenic source. Consideration of mass balance, overall solute chemistry, and examination of nonsulfide dissolution residue, however, suggests that both types of sample reflect primary fluid Sr composition. We thus adopt the working hypothesis that Sr isotopic composition in fluids at the time of hydrothermal mineralization was highly variable. The observed results for the Viburnum Trend do not conform well to expected trends for Mississippi Valley-type(MVT) mineralization based primarily on analyses of gangue carbonates, barite, and fluorite. Fluid inclusion Sr in some of the Viburnum Trend samples is more radiogenic than in the host dolomite but only moderately so; in other samples, notably main-stage octahedral galena, fluid inclusion Sr composition is within the range observed for the host dolomite. In contrast, Sr in some of the sulfides is very radiogenic, much more so than previously reported for MVT minerals, and is very radiogenic early in the paragenesis (pyrite, chalcopyrite, sphalerite), less radiogenic during main-stage ore deposition, and again more radiogenic in later paragenetic stages. C1 US GEOL SURVEY,DENVER,CO 80225. RP BRANNON, JC (reprint author), WASHINGTON UNIV,MCDONNELL CTR SPACE SCI,DEPT EARTH & PLANETARY SCI,ST LOUIS,MO 63130, USA. NR 49 TC 39 Z9 43 U1 3 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1991 VL 55 IS 5 BP 1407 EP 1419 DI 10.1016/0016-7037(91)90317-X PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FM716 UT WOS:A1991FM71600016 ER PT J AU SAREWITZ, DR LEWIS, SD AF SAREWITZ, DR LEWIS, SD TI THE MARINDUQUE INTRAARC BASIN, PHILIPPINES - BASIN GENESIS AND INSITU OPHIOLITE DEVELOPMENT IN A STRIKE-SLIP SETTING SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID PULL-APART BASINS; WESTERN PACIFIC; MARGINAL BASINS; SEA PLATE; EVOLUTION; ORIGIN; CALIFORNIA; FAULT; LUZON; TECTONICS AB The Marinduque basin is a marine intra-arc basin in the north-central Philippine volcanic arc system. A suite of marine geophysical observations show the basin as a whole to be rhombic in shape, with its long axis trending north-northwest. A conspicuous volcanic ridge trends east-northeast across the basin, dividing it into two smaller active depocenters. Symmetric linear magnetic anomalies, striking parallel to, and centered over, the central volcanic ridge indicate that it formed by extension in a north-south direction by a process analogous to sea-floor spreading. Geometric and temporal relations between the central volcanic ridge and several en echelon sets of north-trending, left-stepping faults indicate that sea-floor spreading occurred in the extensional stepover zone of a left-lateral, strike-slip fault system, and that the Marinduque basin as a whole is a composite pull-apart basin whose floor is in part composed of oceanic-type crust. The evolution of the central volcanic ridge presents an actualistic model for in situ development and emplacement of ophiolites in an island-arc setting. The presently active, left-lateral Philippine fault zone truncated the eastern flank of the basin as well as the central volcanic ridge, following their initial formation. Shortening associated with a probable restraining bend in the Philippine fault has resulted in uplift of basin flank sediments, which have been thrust back toward the basin interior. The Philippine fault has also displaced fragments of the ridge and basin floor toward the north. The overall history of the Marinduque basin further suggests that strike-slip processes may play an important role in the origin and growth of intra-are basins. Such basins may ultimately become isolated in a forearc or backarc setting. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP SAREWITZ, DR (reprint author), CORNELL UNIV,DEPT GEOL SCI,ITHACA,NY 14853, USA. NR 76 TC 32 Z9 32 U1 0 U2 3 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD MAY PY 1991 VL 103 IS 5 BP 597 EP 614 DI 10.1130/0016-7606(1991)103<0597:TMIABP>2.3.CO;2 PG 18 WC Geosciences, Multidisciplinary SC Geology GA FK057 UT WOS:A1991FK05700001 ER PT J AU SMITH, GI AF SMITH, GI TI ANOMALOUS FOLDS ASSOCIATED WITH THE EAST-CENTRAL PART OF THE GARLOCK FAULT, SOUTHEAST CALIFORNIA SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID SAN-ANDREAS FAULT; STRAIN ACCUMULATION; TECTONIC ROTATION; STRESS; STATE AB The east-central part of the left-lateral Garlock fault, in southeast California, is associated with three broad folds that trend and plunge northeast. The folds, which lie north, south, and astride the fault, postdate deposition of alluvial gravels that at one time formed a continuous northwest-sloping fan; the gravels rest conformably on lake beds that contain the Lava Creek B ash bed (0.62 Ma). The anticline, named after Christmas Canyon, has vertical relief of as much as 100 m. Topographic profiles suggest that the gravels exposed along the synclinal troughs to its southeast (Pilot Knob Valley syncline) and northwest (Teagle Wash syncline) lie at about the same elevations as they did when part of the originally active fan, implying that the synclines are passive results of the anticline development. If so, the original slope of the middle Pleistocene alluvial sediment sheet was about 0.6-degrees northwest. The age and dimensional controls allow calculation of the rates of tilting and horizontal shortening. Corrected tilting rates vary from about 2.5-degrees to 4.7-degrees/m.y.; the total shortening of about 7.5 m developed at a minimum rate of 12.5 m/m.y. The orientations of these folds imply northwest-southeast compression, which is anomalous when viewed in the context of regional tectonics. The left-lateral Garlock fault and the north-northwest-trending Searles Valley syncline and Slate Range anticline imply northeast-southwest compression, which geophysical criteria confirm. Geologic evidence of northwest-southeast compressional deformation, dating to pre-Miocene (Paleocene?) time, however, is known from several other localities along the Garlock fault. These anomalous features are interpreted as evidence that episodes of northwest-southeast compression along the Garlock fault do occur, and although oriented about 90-degrees from the average of conventional - and presently observed - compression directions, they have occurred during much (most?) of the Cenozoic Era, including the past 0.6 m.y. RP SMITH, GI (reprint author), US GEOL SURVEY,MS 902,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 38 TC 4 Z9 4 U1 0 U2 2 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD MAY PY 1991 VL 103 IS 5 BP 615 EP 624 DI 10.1130/0016-7606(1991)103<0615:AFAWTE>2.3.CO;2 PG 10 WC Geosciences, Multidisciplinary SC Geology GA FK057 UT WOS:A1991FK05700002 ER PT J AU NELSON, WH AF NELSON, WH TI KINEMATIC MODEL OF A CONTINUOUS HEART MOUNTAIN ALLOCHTHON - DISCUSSION SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Discussion RP NELSON, WH (reprint author), US GEOL SURVEY,MS 904,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD MAY PY 1991 VL 103 IS 5 BP 718 EP 722 DI 10.1130/0016-7606(1991)103<0718:KMOACH>2.3.CO;2 PG 5 WC Geosciences, Multidisciplinary SC Geology GA FK057 UT WOS:A1991FK05700009 ER PT J AU MOORE, JC DIEBOLD, J FISHER, MA SAMPLE, J BROCHER, T TALWANI, M EWING, J VONHUENE, R ROWE, C STONE, D STEVENS, C SAWYER, D AF MOORE, JC DIEBOLD, J FISHER, MA SAMPLE, J BROCHER, T TALWANI, M EWING, J VONHUENE, R ROWE, C STONE, D STEVENS, C SAWYER, D TI EDGE DEEP SEISMIC-REFLECTION TRANSECT OF THE EASTERN ALEUTIAN ARC-TRENCH LAYERED LOWER CRUST REVEALS UNDERPLATING AND CONTINENTAL GROWTH SO GEOLOGY LA English DT Article ID KODIAK SHELF; ALASKA; ISLANDS; WEDGES; ROCKS AB An EDGE deep crustal seismic reflection transect of the eastern Aleutian arc-trench traces oceanic crust and Moho more than 200 km beneath the accretionary prism to depths of more than 30 km. These horizons project beneath a prominent sequence of layered reflectors that extends from about 9 to 35 km beneath the Mesozoic core of the prism. Earthquake hypocenters imply continuity of the downgoing lithosphere from the base of the layered reflectors to beneath and beyond the active Augustine volcano. Rapid lateral growth of the prism in Eocene-Oligocene time coincided with uplift of the Mesozoic core of the prism. During lateral growth, maintenance of critical taper requires thickening, either by internal deformation or underplating. Because exposed rocks show only modest postemplacement shortening, thickening most likely occurred by underplating, probably of the layered reflectors. The overall geometry of the layered reflectors is reminiscent of nappe structures, and their emplacement may represent crustal-scale duplexing associated with underplating. The EDGE reflection data and borehole results indicate that the shelf edge is marked by an active out-of-sequence thrust that separates the Paleogene and Neogene prisms. This thrust apparently developed in response to the prism's need to maintain critical taper and demonstrates that contrasts in lithology can result from mechanisms other than terrane emplacement. C1 COLUMBIA UNIV,LAMONT DOHERTY GEOL OBSERV,PALISADES,NY 10964. US GEOL SURVEY,MENLO PK,CA 94025. UNIV CALIF LOS ANGELES,DEPT EARTH & SPACE SCI,LOS ANGELES,CA 90024. HOUSTON AREA RES CTR,THE WOODLANDS,TX 77381. GEOMAR,W-2300 KIEL 14,GERMANY. UNIV ALASKA,INST GEOPHYS,FAIRBANKS,AK 99701. RICE UNIV,DEPT GEOL,HOUSTON,TX 77005. RP MOORE, JC (reprint author), UNIV CALIF SANTA CRUZ,DEPT EARTH SCI,SANTA CRUZ,CA 95064, USA. RI Sawyer, Dale/B-7667-2013; Sample, James/A-9622-2015 OI Sawyer, Dale/0000-0002-6915-1486; NR 24 TC 73 Z9 74 U1 0 U2 5 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 1991 VL 19 IS 5 BP 420 EP 424 DI 10.1130/0091-7613(1991)019<0420:EDSRTO>2.3.CO;2 PG 5 WC Geology SC Geology GA FK104 UT WOS:A1991FK10400002 ER PT J AU WRIGHT, JE WOODEN, JL AF WRIGHT, JE WOODEN, JL TI NEW SR, ND, AND PB ISOTOPIC DATA FROM PLUTONS IN THE NORTHERN-GREAT-BASIN - IMPLICATIONS FOR CRUSTAL STRUCTURE AND GRANITE PETROGENESIS IN THE HINTERLAND OF THE SEVIER THRUST BELT SO GEOLOGY LA English DT Article ID WESTERN UNITED-STATES; MANTLE EVOLUTION; TERTIARY GRANITE; OROGENIC BELT; ORIGIN; ROCKS; UTAH; METAMORPHISM AB The influence of tectonic setting and age on the variation of isotopic signatures of granitic plutons in the northern Great Basin has, in general, not been apparent from previous investigations. Although Elison et al. pointed out isotopic differences between Jurassic and younger plutons near the 0.706 Sr isopleth, and Farmer and DePaolo noted that there might be a difference between Cenozoic vs. Mesozoic plutonic rocks in the eastern part of the northern Great Basin, neither of these studies revealed the remarkable correlation between isotopic signature, age, and tectonic setting shown by our expanded Sr, Nd, and Pb isotopic data base. Jurassic-Early Cretaceous plutons in the northern Great Basin have a limited range of Sr and Nd isotopic values that cluster near bulk earth. All but one of these plutons have epsilon-Nd values less negative than-7 despite their location both to the west and east of the epsilon-Nd = -7 line. Construction of Sr 0.706 and epsilon-Nd = -7 isotopic boundaries is virtually impossible for plutons of this age range. In contrast, Upper Cretaceous peraluminous granites east of the epsilon-Nd = -7 line have very negative epsilon-Nd values and high initial Sr ratios, and they appear to represent essentially pure crustal melts. The data favor a model that equates generation of these plutons via crustal thickening associated with the Sevier thrust belt. Cenozoic plutons appear to be mixtures of mantle and crustal reservoirs, and their isotopic systematics, along with those of the Late Cretaceous age plutonic suite, define a previously unrecognized, approximately east-west-trending crustal boundary between predominantly Archean crust to the north and predominantly Proterozoic crust to the south. The isotopic data from the Jurassic-Early Cretaceous plutonic suite do not reflect the presence of this boundary, suggesting that the isotopic systematics of this plutonic suite may not have been controlled by the same variations in crustal and/or mantle lithospheric structure at depth. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP WRIGHT, JE (reprint author), RICE UNIV,DEPT GEOL & GEOPHYS,HOUSTON,TX 77251, USA. NR 27 TC 55 Z9 55 U1 1 U2 4 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 1991 VL 19 IS 5 BP 457 EP 460 DI 10.1130/0091-7613(1991)019<0457:NSNAPI>2.3.CO;2 PG 4 WC Geology SC Geology GA FK104 UT WOS:A1991FK10400011 ER PT J AU MADDENMCGUIRE, DJ MARSH, SP AF MADDENMCGUIRE, DJ MARSH, SP TI LOWER PALEOZOIC HOST ROCKS IN THE GETCHELL GOLD BELT - SEVERAL DISTINCT ALLOCHTHONS OR A SEQUENCE OF CONTINUOUS SEDIMENTATION SO GEOLOGY LA English DT Article AB The lower Paleozoic rocks that host gold deposits along the Getchell gold belt in Humboldt County, Nevada, represent several allochthonous terranes rather than a sequence of continuous deposition. The term "terrane" is used only in a descriptive sense. Evidence for allochthonous terranes in this area includes fault boundaries and differences in age, lithology, and structural style among several rock sequences. The two most widespread and distinct terranes in the area are (1) the Osgood terrane, which consists of intensely deformed, regionally metamorphosed, marine rocks (Lower Cambrian Osgood Mountain Quartzite, Lower Cambrian to Lower Ordovician Preble Formation, and some rocks currently mapped as Comus Formation) and (2) the Getchell terrane, which consists of less deformed chert, clastic sedimentary rocks, and volcanic rocks (rocks mapped as Valmy and Vinini Formations, including Lower and Upper Ordovician and Lower Silurian strata in this region). Osgood-terrane bedding and foliation dip predominantly eastward, and folds verge westward. Getchell-terrane folds verge southeastward. The Comus Formation, which is Middle Ordovician at its type locality on Edna Mountain, represents a third terrane (Iron Point terrane) situated structurally between the Osgood and Getchell terranes. Use of the unit name Comus Formation outside the type locality has created confusion and needs reexamination. Some of the rocks currently mapped as Comus Formation might really be part of the other terranes. RP MADDENMCGUIRE, DJ (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,MS 973,DENVER,CO 80225, USA. NR 22 TC 7 Z9 7 U1 0 U2 1 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 1991 VL 19 IS 5 BP 489 EP 492 DI 10.1130/0091-7613(1991)019<0489:LPHRIT>2.3.CO;2 PG 4 WC Geology SC Geology GA FK104 UT WOS:A1991FK10400019 ER PT J AU WISE, DU BELT, ES LYONS, PC AF WISE, DU BELT, ES LYONS, PC TI CLASTIC DIVERSION BY FOLD SALIENTS AND BLIND THRUST RIDGES IN COAL-SWAMP DEVELOPMENT SO GEOLOGY LA English DT Article ID APPALACHIAN BASIN; NORTH-AMERICA; USA; SEQUENCES; VIRGINIA; MODEL; BED AB Abrupt shifts from single widespread coal swamps to coarse siliciclastic alluvial channel deposits occur in at least five coal beds and zones within the Pennsylvanian Allegheny Formation. One of these, the Upper Freeport coal zone, was deposited over an area at least 200 x 200 km with a spacing of alluvial channels one-half to possibly one-fifth that of the immediately overlying coarse clastics. All these shifts occurred next to the rising Appalachian orogen, far from the eustatic effects of a marine shoreline. Recent models relating coal-swamp formation to isostatic warping of orogenic forelands by tectonic loads surely apply to this environment, but they seem to need an additional, more delicate mechanism to produce such abrupt but widespread switches in grain size and drainage spacing. We propose that irregularities in the advancing front of folds and blind thrusts caused temporary geomorphic diversions into the recessed areas and allowed a widespread coal swamp to form in the sedimentary shadow of the salients, a shadowing process that is occurring today in the central Zagros Mountains of Iraq and Iran. C1 AMHERST COLL,DEPT GEOL,AMHERST,MA 01002. US GEOL SURVEY,NATL CTR,COAL GEOL BRANCH,RESTON,VA 22092. RP WISE, DU (reprint author), UNIV MASSACHUSETTS,DEPT GEOL & GEOG,AMHERST,MA 01003, USA. NR 24 TC 14 Z9 14 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 1991 VL 19 IS 5 BP 514 EP 517 DI 10.1130/0091-7613(1991)019<0514:CDBFSA>2.3.CO;2 PG 4 WC Geology SC Geology GA FK104 UT WOS:A1991FK10400025 ER PT J AU MARINCOVICH, L POWELL, CL AF MARINCOVICH, L POWELL, CL TI HIGH-LATITUDE APPLICATION OF SR-87 SR-86 - CORRELATION OF NUWOK BEDS ON NORTH SLOPE, ALASKA, TO STANDARD OLIGOCENE CHRONOSTRATIGRAPHY - COMMENT SO GEOLOGY LA English DT Note RP MARINCOVICH, L (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD MAY PY 1991 VL 19 IS 5 BP 537 EP 538 PG 2 WC Geology SC Geology GA FK104 UT WOS:A1991FK10400034 ER PT J AU KENNETT, BLN ENGDAHL, ER AF KENNETT, BLN ENGDAHL, ER TI TRAVELTIMES FOR GLOBAL EARTHQUAKE LOCATION AND PHASE IDENTIFICATION SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article DE BODY WAVES; CORE PHASES; EARTHQUAKE LOCATION; SEISMIC PHASE IDENTIFICATION; TRAVELTIMES ID TIMES AB Over the last three years, a major international effort has been made by the Sub-Commission on Earthquake Algorithms of the International Association of Seismology and the Physics of the Earth's Interior (IASPEI) to generate new global traveltime tables for seismic phases to update the tables of Jeffreys & Bullen (1940). The new tables are specifically designed for convenient computational use, with high-accuracy interpolation in both depth and range. The new iasp91 traveltime tables are derived from a radially stratified velocity model which has been constructed so that the times for the major seismic phases are consistent with the reported times for events in the catalogue of the International Seismological Centre (ISC) for the period 1964-1987. The baseline for the P-wave traveltimes in the iasp91 model has been adjusted to provide only a small bias in origin time for well-constrained events at the main nuclear testing sites around the world. For P-waves at teleseismic distances, the new tables are about 0.7s slower than the 1968 P-tables (Herrin 1968) and on average about 1.8-1.9 s faster than the Jeffreys & Bullen (1940) tables. For S-waves the teleseimic times lie between those of the JB tables and the results of Randall (1971). Because the times for all phases are derived from the same velocity model, there is complete consistency between the traveltimes for different phases at different focal depths. The calculation scheme adopted for the new iasp91 tables is that proposed by Buland & Chapman (1983). Tables of delay time as a function of slowness are stored for each traveltime branch, and interpolated using a specially designed tau spline which takes care of square-root singularities in the derivative of the traveltime curve at certain critical slownesses. With this representation, once the source depth is specified, it is straightforward to find the traveltime explicitly for a given epicentral distance. The computational cost is no higher than a conventional look-up table, but there is increased accuracy in constructing the traveltimes for a source at arbitrary depth. A further advantage over standard tables is that exactly the same procedure can be used for each phase. For a given source depth, it is therefore possible to generate very rapidly a comprehensive list of traveltimes and associated derivatives for the main seismic phases which could be observed at a given epicentral distance. C1 US GEOL SURVEY,DENVER FED CTR,NATL EARTHQUAKE INFORMAT CTR,DENVER,CO 80225. RP KENNETT, BLN (reprint author), AUSTRALIAN NATL UNIV,RES SCH EARTH SCI,GPO BOX 4,CANBERRA,ACT 2601,AUSTRALIA. OI Kennett, Brian/0000-0003-2206-5350 NR 26 TC 1739 Z9 1846 U1 17 U2 89 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0956-540X J9 GEOPHYS J INT JI Geophys. J. Int. PD MAY PY 1991 VL 105 IS 2 BP 429 EP 465 DI 10.1111/j.1365-246X.1991.tb06724.x PG 37 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FL165 UT WOS:A1991FL16500012 ER PT J AU LOCKNER, D HICKMAN, S KUKSENKO, V PONOMAREV, A SIDORIN, A BYERLEE, J KHAKAEV, B AF LOCKNER, D HICKMAN, S KUKSENKO, V PONOMAREV, A SIDORIN, A BYERLEE, J KHAKAEV, B TI LABORATORY-DETERMINED PERMEABILITY OF CORES FROM THE KOLA SUPERDEEP WELL, USSR SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ROCK AB We have conducted constant flow-rate permeability measurements on three core samples taken from the 12-km-deep well on the Kola Peninsula, USSR. All cores are from 11.4 - 12.0 km depth. Pore pressures, P(p), used in these permeability measurements ranged from 112 - 117 MPa. Measurements were performed at effective confining pressures (P(eff) = P(c) - P(p)) ranging from 10 to 400 MPa. The resulting permeabilities varied from approximately 2.5 x 10(-17) m2 (25-mu-Da) at a P(eff) of 10 MPa to 1 x 10(-22) m2 (0.1 nDa) at a P(eff) of 300 MPa. The unusual sensitivity of permeability to P(eff) exhibited by these samples is most likely the result of severe stress-relief crack damage that occurred during coring and sample retrieval. This strong pressure dependence underscores the importance of measuring permeability at in situ pressures to obtain meaningful bounds on in situ matrix permeabilities in this well. In an attempt to infer closure pressure of these stress-relief cracks, and provide estimates of in situ P(eff), we have analyzed the pressure dependence of permeability, resistivity and crack porosity. By applying an equivalent-channel-model analysis, these data appear consistent with either an in situ pore pressure exceeding the hydrostat by as much as 100 MPa or a hydrostatic P(p) and sub-lithostatic in situ vertical stress. In either case, if this closure pressure accurately reflects the in situ confining pressure, then an upper bound on in situ matrix permeabilities would be 1 x 10(-20) to 2 x 10(-19) m2 for the samples studied. C1 MINIST GEOL USSR,OBEDINENIE NEDRA,JAROSLAVL 150003,USSR. USSR ACAD SCI,AF IOFFE PHYS TECH INST,LENINGRAD 194021,USSR. USSR ACAD SCI,INST PHYS EARTH,MOSCOW 123810,USSR. RP LOCKNER, D (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. RI Ponomarev, Alexander/J-7767-2013; Kuksenko, Victor/M-7793-2014 NR 10 TC 11 Z9 11 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY PY 1991 VL 18 IS 5 BP 881 EP 884 DI 10.1029/91GL00782 PG 4 WC Geosciences, Multidisciplinary SC Geology GA FL206 UT WOS:A1991FL20600022 ER PT J AU FOURNIER, RO AF FOURNIER, RO TI THE TRANSITION FROM HYDROSTATIC TO GREATER THAN HYDROSTATIC FLUID PRESSURE IN PRESENTLY ACTIVE CONTINENTAL HYDROTHERMAL SYSTEMS IN CRYSTALLINE ROCK SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Fluid flow at hydrostatic pressure (P(h)) is relatively common through fractures in silicic and in mafic crystalline rocks where temperatures are less than about 350-370-degrees-C. In contrast, pore-fluid pressure (P(f)) > P(h) has been encountered at the bottom of 3 geothermal exploration wells that attained temperatures > 370-degrees-C (at Larderello, Italy, at Nesjavellir, Iceland, and at The Geysers, California). Chemical sealing by deposition of minerals in veins appears to have allowed the development of the high P(f) encountered in the above wells. The upper limit for the magnitude of P(f) that can be attained is controlled by either the onset of shear fracturing (where differential stress is relatively high) that reopens clogged veins, or the hydraulic opening of new or old fractures (at relatively low values of differential stress). The brittle-plastic transition for silicic rocks can occur at temperatures as high as 370-400-degrees-C in tectonically active regions. In regions where high-temperature geothermal systems develop and persist, it appears that either strain rates commonly are in the range 10(-12) to 10(-13), or that silicic rocks in the shallow crust generally behave rheologically more like wet quartz diorite than wet Westerly granite. RP FOURNIER, RO (reprint author), US GEOL SURVEY,MS-910,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 20 TC 113 Z9 113 U1 3 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY PY 1991 VL 18 IS 5 BP 955 EP 958 PG 4 WC Geosciences, Multidisciplinary SC Geology GA FL206 UT WOS:A1991FL20600041 ER PT J AU REYNOLDS, RL FISHMAN, NS HUDSON, MR AF REYNOLDS, RL FISHMAN, NS HUDSON, MR TI SOURCES OF AEROMAGNETIC ANOMALIES OVER CEMENT OIL-FIELD (OKLAHOMA), SIMPSON OIL-FIELD (ALASKA), AND THE WYOMING-IDAHO-UTAH THRUST BELT SO GEOPHYSICS LA English DT Article ID DIAGENETIC MAGNETITE; OVERTHRUST BELT; MAGNETIZATION; HYDROCARBONS; LIMESTONES; PETROLEUM; FORELAND; SULFIDE AB Geochemical and rock magnetic studies, undertaken to determine the causes of magnetic anomalies over Cement oil field (Anadarko basin, Oklahoma), Simpson oil field (North Slope basin, Alaska), and the Wyoming-Idaho-Utah thrust belt, have revealed different magnetic sources developed under different sedimentologic, geochemical, and structural settings. At Cement, ferrimagnetic pyrrhotite (Fe7S8), typically intergrown with more abundant, nonmagnetic pyrite (FeS2), formed as a result of hydrocarbon seepage. Sulfur isotopic data indicate that sulfur in the Fe-S minerals was probably derived from two different sources: (1) isotopically heavy, thermochemical H2S in petroleum, and (2) isotopically light H2S generated by sulfate-reducing bacteria that derived metabolic energy from leaking hydrocarbons or organic compounds derived from hydrocarbons. Although pyrrhotite may make a minor contribution to the reported total magnetic field anomalies at Cement, the measured anomalies are probably mostly caused by man-made features such as buried well casings and pipelines. Magnetite, found in well cuttings from Cement and previously considered the source of the anomalies, is contamination from drilling. At Simpson, ferrimagnetic greigite (Fe3S4) is concentrated locally in Upper Cretaceous beds. A preliminary geochemical study reveals a complicated picture in which early diagenetic chemical and mineralogic changes are variably overprinted by later epigenetic alterations, perhaps related to hydrocarbon seepage. The greigite probably formed at different times from sulfate reduction by bacteria that used either organic compounds derived from hydrocarbons or detrital organic matter, or both, as food sources. Magnetic-property studies suggest the natural remanent magnetization of greigite-bearing rocks may contribute to the magnetic anomalies. In the thrust belt, the Middle Jurassic Preuss Sandstone has magnetizations as much as 0.76 A/m (average 0.14 A/m) west of the Absaroka fault where aeromagnetic anomalies locally correspond to exposures of the Preuss and much lower magnetizations (average 0.44 x 10(-2) A/m) east of the Absaroka fault. The magnetization is carried by rounded titanium-bearing detrital magnetite, commonly concentrated along heavy-mineral laminations. Carbon isotopic compositions of calcite cement (-2.4 to + 1.5 per mil) reflect an absence of organic carbon in the calcite and thus suggest that hydrocarbon had no role in the preservation of the detrital magnetite. Our results show that abiologic and biologic mechanisms can generate different magnetic sulfide minerals in zones of sulfidic hydrocarbon seepage. More commonly, sulfidic seepage could either diminish magnetization by replacement of detrital magnetic minerals with nonmagnetic sulfide minerals, or it would have no effect on magnetization if such detrital minerals were originally absent. An important negative result is the absence of abundant secondary (diagenetic) magnetite in the seepage environments. Although secondary magnetite occurs in some biodegraded crude oils, concentrations of such magnetite capable of producing aeromagnetic anomalies have not been documented. RP REYNOLDS, RL (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,MS 964,DENVER,CO 80225, USA. NR 62 TC 24 Z9 28 U1 0 U2 3 PU SOC EXPLORATION GEOPHYSICISTS PI TULSA PA 8801 S YALE ST, TULSA, OK 74137 SN 0016-8033 J9 GEOPHYSICS JI Geophysics PD MAY PY 1991 VL 56 IS 5 BP 606 EP 617 DI 10.1190/1.1443077 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FL784 UT WOS:A1991FL78400002 ER PT J AU PECK, DL AF PECK, DL TI NATURAL HAZARDS AND PUBLIC PERCEPTION - EARTH SCIENTISTS CAN MAKE THE DIFFERENCE SO GEOTIMES LA English DT Article RP PECK, DL (reprint author), US GEOL SURVEY,WASHINGTON,DC 20242, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER GEOLOGICAL INST PI ALEXANDRIA PA 4220 KING ST, ALEXANDRIA, VA 22302-1507 SN 0016-8556 J9 GEOTIMES JI Geotimes PD MAY PY 1991 VL 36 IS 5 BP 5 EP 5 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FK934 UT WOS:A1991FK93400003 ER PT J AU HELIKER, C WRIGHT, TL AF HELIKER, C WRIGHT, TL TI LAVA-FLOW HAZARDS FROM KILAUEAS CURRENT ERUPTION SO GEOTIMES LA English DT Article RP HELIKER, C (reprint author), HAWAIIAN VOLCANO OBSERV,BOX 51,HAWAII NATL PK,HI 96718, USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU AMER GEOLOGICAL INST PI ALEXANDRIA PA 4220 KING ST, ALEXANDRIA, VA 22302-1507 SN 0016-8556 J9 GEOTIMES JI Geotimes PD MAY PY 1991 VL 36 IS 5 BP 16 EP 18 PG 3 WC Geosciences, Multidisciplinary SC Geology GA FK934 UT WOS:A1991FK93400008 ER PT J AU VROBLESKY, DA LORAH, MM AF VROBLESKY, DA LORAH, MM TI PROSPECTING FOR ZONES OF CONTAMINATED GROUNDWATER DISCHARGE TO STREAMS USING BOTTOM-SEDIMENT GAS-BUBBLES SO GROUND WATER LA English DT Article ID METHANE AB Decomposition of organic-rich bottom sediment in a tidal creek in Maryland results in production of gas bubbles in the bottom sediment during summer and fall. In areas where volatile organic contaminants discharge from ground water, through the bottom sediment, and into the creek, part of the volatile contamination diffuses into the gas bubbles and is released to the atmosphere by ebullition. Collection and analysis of gas bubbles for their volatile organic contaminant content indicate that relative concentrations of the volatile organic contaminants in the gas bubbles are substantially higher in areas where the same contaminants occur in the ground water that discharges to the streams. Analyses of the bubbles located an area of previously unknown ground-water contamination. The method developed for this study consisted of disturbing the bottom sediment to release gas bubbles, and then capturing the bubbles in a polyethylene bag at the water-column surface. The captured gas was transferred either into sealable polyethylene bags for immediate analysis with a photoionization detector or by syringe to glass tubes containing wires coated with an activated-carbon adsorbent. Relative concentrations were determined by mass spectral analysis for chloroform and trichloroethylene. C1 US GEOL SURVEY,TOWSON,MD 21204. RP VROBLESKY, DA (reprint author), US GEOL SURVEY,STEVENSON CTR,DIV WATER RESOURCES,SUITE 129,720 GRACERN RD,COLUMBIA,SC 29210, USA. NR 23 TC 8 Z9 8 U1 0 U2 1 PU GROUND WATER PUBLISHING CO PI COLUMBUS PA 2600 GROUND WATER WAY, COLUMBUS, OH 43219 SN 0017-467X J9 GROUND WATER JI Ground Water PD MAY-JUN PY 1991 VL 29 IS 3 BP 333 EP 340 DI 10.1111/j.1745-6584.1991.tb00523.x PG 8 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA FJ700 UT WOS:A1991FJ70000002 ER PT J AU BERES, M HAENI, FP AF BERES, M HAENI, FP TI APPLICATION OF GROUND-PENETRATING-RADAR METHODS IN HYDROGEOLOGIC STUDIES SO GROUND WATER LA English DT Article AB A ground-penetrating-radar system was used to study selected stratified-drift deposits in Connecticut. Ground-penetrating radar is a surface-geophysical method that depends on the emission, transmission, reflection, and reception of an electromagnetic pulse and can produce continuous high-resolution profiles of the subsurface rapidly and efficiently. Traverse locations on land included a well field in the town of Mansfield, a sand and gravel pit and a farm overlying a potential aquifer in the town of Coventry, and Haddam Meadows State Park in the town of Haddam. Traverse locations on water included the Willimantic River in Coventry and Mansfield Hollow Lake in Mansfield. The penetration depth of the radar signal ranged from about 20 feet in fine-grained glaciolacustrine sediments to about 70 feet in coarse sand and gravel. Some land records in coarse-grained sediments show a distinct, continuous reflection from the water table about 5 to 11 feet below land surface. Parallel reflectors on the records are interpreted as fine-grained sediments. Hummocky or chaotic reflectors are interpreted as cross-bedded or coarse-grained sediments. Other features observed on some of the radar records include the till and bedrock surface. Records collected on water had distinct water-bottom multiples (more than one reflection) and diffraction patterns from boulders. The interpretation of the radar records, which required little or no processing, was verified by using lithologic logs from test holes located along some of the land traverses and near the water traverses. RP BERES, M (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,450 MAIN ST,HARTFORD,CT 06103, USA. NR 34 TC 210 Z9 215 U1 3 U2 28 PU GROUND WATER PUBLISHING CO PI COLUMBUS PA 2600 GROUND WATER WAY, COLUMBUS, OH 43219 SN 0017-467X J9 GROUND WATER JI Ground Water PD MAY-JUN PY 1991 VL 29 IS 3 BP 375 EP 386 DI 10.1111/j.1745-6584.1991.tb00528.x PG 12 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA FJ700 UT WOS:A1991FJ70000007 ER PT J AU LANDA, ER AF LANDA, ER TI LEACHING OF RA-226 FROM COMPONENTS OF URANIUM MILL TAILINGS SO HYDROMETALLURGY LA English DT Article ID TRACE-METALS; DISSOLUTION; RADIUM AB A sequential extraction procedure was used to characterize the geochemical forms of Ra-226 retained by mixtures of quartz sand and a variety of fine-grained rock and mineral species. These mixtures had previously been exposed to the sulfuric acid milling liquor of a simulated acid-leach uranium milling circuit. For most test cases, the major fraction of the Ra-226 was extracted with 1 mol/1 NH4Cl and was deemed to be exchangeable. However, Ra-226 retained by the barite-containing mixture was resistant to both 1 mol/1 NH4Cl and 1 mol/1 HCl extraction. RP LANDA, ER (reprint author), US GEOL SURVEY,431 NATL CTR,RESTON,VA 22092, USA. NR 17 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-386X J9 HYDROMETALLURGY JI Hydrometallurgy PD MAY PY 1991 VL 26 IS 3 BP 361 EP 368 DI 10.1016/0304-386X(91)90010-J PG 8 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA FP187 UT WOS:A1991FP18700007 ER PT J AU ZORIN, YA CORDELL, L AF ZORIN, YA CORDELL, L TI CRUST STRETCHING AT THE BAIKAL RIFT-ZONE FROM GRAVITY-DATA SO IZVESTIYA AKADEMII NAUK SSSR FIZIKA ZEMLI LA Russian DT Article ID RIO-GRANDE RIFT C1 US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. RP ZORIN, YA (reprint author), ACAD SCI USSR,INST EARTH CRUST,IRKUTSK 664003,USSR. NR 12 TC 4 Z9 4 U1 0 U2 0 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0002-3337 J9 IZV AN SSSR FIZ ZEM+ PD MAY PY 1991 IS 5 BP 3 EP 11 PG 9 WC Geosciences, Multidisciplinary SC Geology GA GJ267 UT WOS:A1991GJ26700001 ER PT J AU STEIN, HJ KISH, SA AF STEIN, HJ KISH, SA TI THE SIGNIFICANCE OF RB-SR GLAUCONITE AGES, BONNETERRE FORMATION, MISSOURI - LATE-DEVONIAN EARLY-MISSISSIPPIAN BRINE MIGRATION IN THE MIDCONTINENT SO JOURNAL OF GEOLOGY LA English DT Note ID VALLEY-TYPE DEPOSITS; SOUTHEAST MISSOURI; VIBURNUM-TREND; EAST TENNESSEE; LEAD DISTRICT; ORE-DEPOSITS; OZARK REGION; K-AR; MINERALIZATION; ROCKS AB Rb-Sr mean model ages of 370 +/- 10 Ma for glauconites from the Cambrian lower Bonneterre Formation in southern and central Missouri (in contrast to mean model ages of 389 +/- 7 Ma from the middle and upper Bonneterre) are in excellent agreement with a Rb-Sr isochron age of 359 +/- 22 Ma for glauconites from the Magmont mine (Viburnum Trend) in the southeast Missouri lead district. The lower Bonneterre and Magmont mine ages probably reflect isotopic resetting, most likely associated with dolomitization and/or Mississippi Valley-type ore formation in the southeast Missouri lead district. The temporal relation between widespread dolomitization and ore formation in Missouri is unclear, but mounting evidence for two Devonian disturbances permits the following interpretation: (1) a Devonian timing (380-400 Ma) for widespread dolomitization, and (2) a Late Devonian-Early Mississippian timing (360-370 Ma) for formation in southeast Missouri. A definitive, genetic connection between southeast Missouri ore formation and peak Ouachita-Appalachian orogenesis during Pennsylvanian time (300 Ma) is lacking. Late Devonian-Early Mississippian fluids associated with the earliest stages of collisional tectonics and metamorphism to the south and southeast may have been important in the formation of southeast Missouri ore deposits. These tectonically driven waters may themselves have been the Mississippi Valley-type ore fluids, entering Missouri by way of the Black Warrior basin and Reelfoot rift and/or the Arkoma basin. Alternatively, the movement of orogenic fluids hundreds of kilometers distant may have initiated and distally influenced the migration of more locally derived Mississippi Valley-type ore fluids. Broad regions of Missouri and adjacent areas immediately south and southeast experienced heating and crustal flexing in the Late Devonian, and consequently, preservation of elevated temperatures in Mississippi Valley-type fluids as they move great lateral distances may not be necessary for ore formation in southeast Missouri. RP STEIN, HJ (reprint author), US GEOL SURVEY, DENVER FED CTR, MS 905, DENVER, CO 80225 USA. NR 70 TC 7 Z9 7 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0022-1376 EI 1537-5269 J9 J GEOL JI J. Geol. PD MAY PY 1991 VL 99 IS 3 BP 468 EP 481 PG 14 WC Geology SC Geology GA FL091 UT WOS:A1991FL09100010 ER PT J AU GELLIS, A HEREFORD, R SCHUMM, SA HAYES, BR AF GELLIS, A HEREFORD, R SCHUMM, SA HAYES, BR TI CHANNEL EVOLUTION AND HYDROLOGIC VARIATIONS IN THE COLORADO RIVER BASIN - FACTORS INFLUENCING SEDIMENT AND SALT LOADS SO JOURNAL OF HYDROLOGY LA English DT Article ID EPHEMERAL-STREAM PROCESSES; NORTHWESTERN COLORADO; EROSION; GEOMORPHOLOGY AB Suspended-sediment and dissolved-solid (salt) loads decreased after the early 1940s in the Colorado Plateau portion of the Colorado River basin, although discharge of major rivers - the Colorado, Green and San Juan - did not change significantly. This decline followed a period of high sediment yield caused by arroyo cutting. Reduced sediment loads have previously been explained by a change in sediment sampling procedures or changes in climate, land-use and conservation practices. More recent work has revealed that both decreased sediment production and sediment storage in channels of tributary basins produced the decline of sediment and salt loads. Sediment production and sediment storage are important components of incised-channel evolution, which involves sequential channel deepening, widening and finally floodplain formation. Accordingly, the widespread arroyo incision of the late nineteenth century resulted initially in high sediment loads. Since then, loads have decreased as incised channels (arroyos) have stabilized and begun to aggrade. However, during the 1940s, a period of low peak discharges permitted vegetational colonization of the valley floors, which further reduced sediment loads and promoted channel stabilization. This explanation is supported by experimental studies and field observations. Both geomorphic and hydrologic factors contributed to sediment storage and decreased sediment and salt loads in the upper Colorado River basin. C1 US GEOL SURVEY,FLAGSTAFF,AZ 86001. COLORADO STATE UNIV,DEPT EARTH RESOURCES,FT COLLINS,CO 80523. RP GELLIS, A (reprint author), US GEOL SURVEY,GPO BOX 4424,SAN JUAN,PR 00936, USA. NR 50 TC 17 Z9 17 U1 1 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD MAY PY 1991 VL 124 IS 3-4 BP 317 EP 344 DI 10.1016/0022-1694(91)90022-A PG 28 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA FQ121 UT WOS:A1991FQ12100009 ER PT J AU BOGGS, JF LOCHMILLER, RL MCMURRY, ST LESLIE, DM ENGLE, DM AF BOGGS, JF LOCHMILLER, RL MCMURRY, ST LESLIE, DM ENGLE, DM TI CUTEREBRA INFESTATIONS IN SMALL-MAMMAL COMMUNITIES AS INFLUENCED BY HERBICIDES AND FIRE SO JOURNAL OF MAMMALOGY LA English DT Article ID UNBURNED TALLGRASS PRAIRIE; TIMBERS EXPERIMENTAL RANGE; RESPONSES AB The impact of habitat alterations created by five brush-management systems (herbicide applications with or without burning) on Cuterebra sp. infestations of a host community (n = 811) of small mammals was examined on typical cross-timbers rangeland in Payne Co., Oklahoma, from summer 1986 to 1988. Prevalence of Cuterebra sp. infestations in host communities inhabiting pastures treated with tebuthiuron was greater than those treated with triclopyr in 1986. Prevalence on unburned pastures was greater than annually burned herbicide-treated pastures in 1986. Intensity of infestation was not influenced by habitat modification. Burning might have killed soil-dwelling larvae, and tebuthiuron treatment probably created an abundance of topographical summits for aggregation of Cuterebra sp. C1 OKLAHOMA STATE UNIV,US FISH & WILDLIFE SERV,OKLAHOMA COOPERAT FISH & WILDLIFE RES UNIT,STILLWATER,OK 74078. OKLAHOMA STATE UNIV,DEPT AGRON,STILLWATER,OK 74078. RP BOGGS, JF (reprint author), OKLAHOMA STATE UNIV,DEPT ZOOL,STILLWATER,OK 74078, USA. NR 35 TC 5 Z9 6 U1 0 U2 3 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD MAY PY 1991 VL 72 IS 2 BP 322 EP 327 DI 10.2307/1382102 PG 6 WC Zoology SC Zoology GA FN196 UT WOS:A1991FN19600009 ER PT J AU ARTHUR, SM KROHN, WB AF ARTHUR, SM KROHN, WB TI ACTIVITY PATTERNS, MOVEMENTS, AND REPRODUCTIVE ECOLOGY OF FISHERS IN SOUTH-CENTRAL MAINE SO JOURNAL OF MAMMALOGY LA English DT Article ID HABITAT USE; MARTEN AB Most activity of adult fishers (Martes pennanti) occurred shortly before sunrise and after sunset, but some activity occurred throughout the day and night. Males and females showed similar amounts of activity, and both were active more frequently in summer than winter. Movements of males were greatest during the spring breeding season; nonreproductive females moved similar distances during all seasons. Eleven maternal dens were in tree cavities; the denning period lasted 8-12 weeks from March through May. The maximum annual parturition rate among females greater-than-or-equal-to 2 years old was 75% (n = 4). This was less than pregnancy rates indicated by corpora lutea, and suggested that some pregnancies were unsuccessful. We hypothesize that delayed implantation allows mating to occur at a favorable time for adults, and births to occur when offspring have the maximum time for development before winter. C1 UNIV MAINE,US FISH & WILDLIFE SERV,MAINE COOPERAT FISH & WILDLIFE RES UNIT,ORONO,ME 04469. NR 27 TC 18 Z9 18 U1 3 U2 15 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD MAY PY 1991 VL 72 IS 2 BP 379 EP 385 DI 10.2307/1382110 PG 7 WC Zoology SC Zoology GA FN196 UT WOS:A1991FN19600017 ER PT J AU BOHLEN, SR AF BOHLEN, SR TI ON THE FORMATION OF GRANULITES SO JOURNAL OF METAMORPHIC GEOLOGY LA English DT Article; Proceedings Paper CT MEETING OF THE INTERNATIONAL GEOLOGICAL CORRELATION PROGRAM ON GRANITE METAMORPHISM CY JUL, 1989 CL UNIV NEW SOUTH WALES, KENSINGTON, AUSTRALIA SP INT GEOL CORRELAT PROGRAM HO UNIV NEW SOUTH WALES DE BAROMETRY; CRUSTAL EVOLUTION; GRANULITE; P-T-T PATH, THERMOMETRY ID TEMPERATURE-TIME PATHS; CONTINENTAL-CRUST; ENDERBY-LAND; EVOLUTION; METAMORPHISM; ANTARCTICA; AUSTRALIA; GNEISSES; TERRAINS; COMPLEX AB The tectonic settings for the formation and evolution of regional granulite terranes and the lowermost continental crust can be deduced from pressure-temperature-time (P-T-time) paths and constrained by petrological and geophysical considerations. P - T conditions deduced for regional granulites require transient, average geothermal gradients of greater than 35-degrees-C km-1, implying minimum heat flow in excess of 100 mW m-2. Such high heat flow is probably caused by magmatic heating. Tectonic settings wherein such conditions are found include convergent plate margins, continental rifts, hot spots and at the margins of large, deep-seated batholiths. However, particular P-T-time paths do not allow specific tectonic settings to be distinguished at this time. Under different conditions, both clockwise, CW (P(max) attained before T(max)), and anticlockwise, ACW (P(max) attained slightly after T(max)), paths are possible in the same tectonic setting. Both CW and ACW end-member paths can yield nearly isobaric cooling, IBC, paths. Such cooling paths are clearly not an artefact of thermobarometry, but can be constrained by solid-solid and devolatilization equilibria and geophysical modelling. In terms of understanding the evolution of the deep crust, a potentially significant group of regional granulite terranes are those that show evidence for ACW-IBC paths. Such paths are the likely result of: (i) episodic igneous activity resulting in intrusions within all levels of the crust, (ii) thickening of the crust by magmatic underplating, (iii) slow uplift as a result of the formation of a deep, garnet-rich crustal root and (iv) excavation resulting from a later tectonic event unrelated to that resulting in the formation of the granulites. The later event might be triggered by the delamination of the garnet-rich, lowermost crust. RP BOHLEN, SR (reprint author), US GEOL SURVEY,MS-910,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 39 TC 153 Z9 159 U1 1 U2 9 PU BLACKWELL SCIENCE INC PI CAMBRIDGE PA 238 MAIN ST, CAMBRIDGE, MA 02142 SN 0263-4929 J9 J METAMORPH GEOL JI J. Metamorph. Geol. PD MAY PY 1991 VL 9 IS 3 BP 223 EP 229 DI 10.1111/j.1525-1314.1991.tb00518.x PG 7 WC Geology SC Geology GA FK043 UT WOS:A1991FK04300002 ER PT J AU POJETA, J AF POJETA, J TI VISIONS FOR PALEONTOLOGY SO JOURNAL OF PALEONTOLOGY LA English DT Editorial Material RP POJETA, J (reprint author), US GEOL SURVEY,NATL CTR,PALEONTOL & STRATIG BRANCH,MS 982,RESTON,VA 22092, USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU PALEONTOLOGICAL SOC INC PI ITHACA PA 1259 TRUMANSBURG ROAD, ITHACA, NY 14850 SN 0022-3360 J9 J PALEONTOL JI J. Paleontol. PD MAY PY 1991 VL 65 IS 3 BP 347 EP 354 PG 8 WC Paleontology SC Paleontology GA FN931 UT WOS:A1991FN93100001 ER PT J AU PRATT, LM FORCE, ER POMEROL, B AF PRATT, LM FORCE, ER POMEROL, B TI COUPLED MANGANESE AND CARBON-ISOTOPIC EVENTS IN MARINE CARBONATES AT THE CENOMANIAN-TURONIAN BOUNDARY SO JOURNAL OF SEDIMENTARY PETROLOGY LA English DT Article ID GREENHORN FORMATION; ORGANIC-CARBON; ORIGIN; COLORADO; KANSAS; OCEAN; MODEL; IRON AB The boundary interval between the Cenomanian and Turonian stages of the Upper Cretaceous shows a positive excursion in the carbon isotopic composition of organic matter and carbonate in many epicontinental and oceanic sections of the Atlantic-Tethyan realm. Some of the studied epicontinental sections contain an excursion in the manganese content of carbonates coincident with the shift in carbon isotopic values. In a key reference section at Pueblo, Colorado, the stratigraphic position and magnitude of the manganese excursion are described with respect to the carbon isotopic excursion. Coincident excursions in manganese contents and carbon isotopic values are verified for a section in Normandy, France. The depositional setting for these two sections is persistently to intermittently well oxygenated with the accumulation of interbedded chalky and marly sediments. No shift in manganese values was detected through the isotopic excursion in a section from northern Nebraska, where fossils are preserved only as bedding-plane impressions due to extensive early diagnetic dissolution of carbonate. The carbon-isotopic and manganese excursions begin at the same stratigraphic position, but manganese contents return to background values within the lower half of the carbon-isotopic excursion. The relative timing and duration of these signals suggest the existence of a large manganese reservoir that was rapidly mobilized. Transfer of manganese from deep-sea oxides (Mn4+) to epicontinental carbonates (Mn2+) is inferred to have occurred during expansion of oceanic oxygen-minimum zones with associated changes in redox gradients and boundaries. Simultaneous excursions in carbon isotopic values and manganese contents can occur at sites of carbonate accumulation when the carbon and manganese cycles are linked through the reducing potential of widespread oxygen-depleted water masses. C1 UNIV ARIZONA,US GEOL SURVEY,TUCSON,AZ 85721. UNIV PARIS 12,GEOL LAB,F-94010 CRETEIL,FRANCE. RP PRATT, LM (reprint author), INDIANA UNIV,DEPT GEOL SCI,BLOOMINGTON,IN 47405, USA. NR 68 TC 57 Z9 59 U1 0 U2 4 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 SN 0022-4472 J9 J SEDIMENT PETROL PD MAY PY 1991 VL 61 IS 3 BP 370 EP 383 PG 14 WC Geology SC Geology GA FM981 UT WOS:A1991FM98100006 ER PT J AU POLGARI, M OKITA, PM HEIN, JR AF POLGARI, M OKITA, PM HEIN, JR TI STABLE ISOTOPE EVIDENCE FOR THE ORIGIN OF THE URKUT MANGANESE ORE DEPOSIT, HUNGARY SO JOURNAL OF SEDIMENTARY PETROLOGY LA English DT Article ID SYNSEDIMENTARY HYDROTHERMAL ORIGIN; GEOCHEMICAL EVIDENCE; GONZEN SARGANS; HELVETIC ALPS; BLACK SHALES; SEDIMENTS; SWITZERLAND; CARBONATES AB The stratiform sedimentary manganese ore deposit at Urkut, Hungary contains primary ore that is exclusively manganese carbonate. It shares many geological, sedimentological, mineralogical, and geochemical characteristics with other organic-rich, sediment-hosted, marine manganese deposits. Samples from two stratigraphic sequences through the marlstone-hosted Mn carbonate ore at Urkut were studied. Stable isotope compositions of both Mn-rich and Mn-poor carbonates were analyzed and are discussed, together with the geologic background of the deposit, rock and mineral chemistry, and x-ray diffraction mineralogy. The delta-C-13 values of carbonates (-1.24 to -30.78 parts-per-thousand) show a negative linear correlation with Mn contents and a negative exponential correlation with total organic carbon contents. These relations suggest that the Urkut deposit was produced by early diagenetic precipitation of manganese carbonate. Data are consistent with models for bacterial metabolic pathways. Thus, mineralization was a consequence of bacterially mediated diagenetic reactions that involved Mn reduction via one or two coupled reactions: the oxidation of organic matter with Mn oxyhydroxide reduction, or the oxidation of FeS produced as a byproduct of seawater sulfate reduction with Mn oxyhydroxide reduction. Oxygen-deficient water in the depositional basin acted as a carrier and reservoir for Mn+2 before its deposition. C1 US GEOL SURVEY,RESTON,VA 22092. US GEOL SURVEY,MENLO PK,CA 94025. RP POLGARI, M (reprint author), HUNGARIAN ACAD SCI,GEOCHEM RES LAB,BUDAORSI UT 45,H-1112 BUDAPEST,HUNGARY. NR 34 TC 57 Z9 59 U1 0 U2 1 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 SN 0022-4472 J9 J SEDIMENT PETROL PD MAY PY 1991 VL 61 IS 3 BP 384 EP 393 PG 10 WC Geology SC Geology GA FM981 UT WOS:A1991FM98100007 ER PT J AU ONSTAD, CA BURKART, MR BUBENZER, GD AF ONSTAD, CA BURKART, MR BUBENZER, GD TI AGRICULTURAL-RESEARCH TO IMPROVE WATER-QUALITY SO JOURNAL OF SOIL AND WATER CONSERVATION LA English DT Article C1 US GEOL SURVEY,IOWA CITY,IA 52244. UNIV WISCONSIN,DEPT AGR ENGN,MADISON,WI 53714. RP ONSTAD, CA (reprint author), USDA ARS,MIDWEST AREA,MORRIS,MN 56267, USA. NR 14 TC 23 Z9 23 U1 0 U2 1 PU SOIL WATER CONSERVATION SOC PI ANKENY PA 7515 N E ANKENY RD, ANKENY, IA 50021-9764 SN 0022-4561 J9 J SOIL WATER CONSERV JI J. Soil Water Conserv. PD MAY-JUN PY 1991 VL 46 IS 3 BP 184 EP 188 PG 5 WC Ecology; Soil Science; Water Resources SC Environmental Sciences & Ecology; Agriculture; Water Resources GA FT165 UT WOS:A1991FT16500008 ER PT J AU CELEBI, M SAFAK, E YOUSSEF, N AF CELEBI, M SAFAK, E YOUSSEF, N TI TORSIONAL RESPONSE OF UNIQUE BUILDING SO JOURNAL OF STRUCTURAL ENGINEERING-ASCE LA English DT Article AB Acceleration response records obtained during the October 1, 1987 Whittier-Narrows earthquake (M(s) = 5.6) from the 32-story, vertically irregular 1100 Wilshire Finance Building, of which the cross section changes from a nominally rectangular shape to a tringular one, are analyzed. The building was instrumented with 21 channels of synchronized sensors, consisting of 12 uniaxial accelerometers deployed throughout the superstructure and connected to a central recording system and three triaxial strong-motion accelerographs in the basement. At each of the four levels of the superstructure, three uniaxial accelerometers were deployed, two parallel and at a distance apart, and the third one orthogonal to the parallel pair. The records permit the identification of the predominantly coupled torsional-translational response of the building and the associated frequency at approximately 0.7-0.8 Hz from the difference between accelerations recorded by the parallel pairs of accelerometers at different levels. This mode corresponds to the second torsional mode. A translational mode at 0.3 Hz is also identified from the records. The center of rigidity of any instrumented level is identified by minimizing the coherence between the relative accelerations and the translational acceleration. Employing system identification techniques provides the modal damping percentage for the second torsional mode as 6-7%. C1 AC MARTIN & ASSOCIATES,LOS ANGELES,CA 90017. RP CELEBI, M (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9445 J9 J STRUCT ENG-ASCE JI J. Struct. Eng.-ASCE PD MAY PY 1991 VL 117 IS 5 BP 1549 EP 1566 PG 18 WC Construction & Building Technology; Engineering, Civil SC Construction & Building Technology; Engineering GA FH169 UT WOS:A1991FH16900015 ER PT J AU LEBO, JA ZAJICEK, JL SCHWARTZ, TR SMITH, LM BEASLEY, MP AF LEBO, JA ZAJICEK, JL SCHWARTZ, TR SMITH, LM BEASLEY, MP TI DETERMINATION OF MONOCYCLIC AND POLYCYCLIC AROMATIC-HYDROCARBONS IN FISH TISSUE SO JOURNAL OF THE ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS LA English DT Article ID TRACE LEVEL HYDROCARBONS; SOLE PAROPHRYS-VETULUS; GAS-CHROMATOGRAPHY; HEPATIC NEOPLASMS; ORGANIC-COMPOUNDS; TOXIC-CHEMICALS; MARINE SEDIMENT; BIOTA; FOODS; ACCUMULATION AB An analytical method is presented in which fish tissue is analyzed for neutral monocyclic and polycyclic aromatic hydrocarbons (AHs) and aromatic sulfur heterocycles (ASHs) by capillary column gas chromatography (CGC) with photoionization detection. The sample enrichment procedure includes saponification with aqueous KOH, acidification of the digestates, and extraction of the aromatic compounds into cyclopentane-dichloromethane. Adsorption chromatography on tandem segments of potassium silicate and silica gel removes 99 % of the coextracted lipid. Final enrichment by gel permeation chromatography eliminates residual biogenic material and potentially interfering alkanes. Relatively volatile monoaromatics are included among the analytes by virtue of the efficiency of the complementary enrichment steps, the use of small quantities of only low-boiling solvents, and the selectivity of the detector. Most targeted compounds (AHs ranging in size from C3-alkylbenzenes through benzo[g,h,i]perylene and ASHs within the same size range) can be determined in 5 g (wet weight) samples of fish tissue at concentrations as low as 20 ng/g. Comparisons are made of recoveries of selected AHs under ordinary and gold fluorescent lighting conditions. RP LEBO, JA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,RTE 2,4200 NEW HAVEN RD,COLUMBIA,MO 65201, USA. NR 33 TC 22 Z9 23 U1 1 U2 8 PU AOAC INTERNATIONAL PI GAITHERSBURG PA 481 NORTH FREDRICK AVE, STE 500, GAITHERSBURG, MD 20877-2504 SN 0004-5756 J9 J ASSOC OFF ANA CHEM PD MAY-JUN PY 1991 VL 74 IS 3 BP 538 EP 544 PG 7 WC Chemistry, Analytical SC Chemistry GA FN229 UT WOS:A1991FN22900023 PM 1874700 ER PT J AU BRUMBAUGH, WG WALTHER, MJ AF BRUMBAUGH, WG WALTHER, MJ TI IMPROVED SELENIUM RECOVERY FROM TISSUE WITH MODIFIED SAMPLE DECOMPOSITION SO JOURNAL OF THE ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS LA English DT Note AB The present paper describes a simple modification of a recently reported decomposition method for determination of selenium in biological tissue by hydride generation atomic absorption. The modified method yielded slightly higher selenium recoveries (3-4%) for selected reference tissues and fish tissue spiked with selenomethionine. Radiotracer experiments indicated that the addition of a small volume of hydrochloric acid to the wet digestate mixture reduced slight losses of selenium as the sample initially went to dryness before ashing. With the modified method, selenium spiked as selenomethionine behaved more like the selenium in reference tissues than did the inorganic spike forms when this digestion modification was used. RP BRUMBAUGH, WG (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,4200 NEW HAVEN RD,COLUMBIA,MO 65201, USA. NR 3 TC 13 Z9 13 U1 0 U2 0 PU AOAC INTERNATIONAL PI GAITHERSBURG PA 481 NORTH FREDRICK AVE, STE 500, GAITHERSBURG, MD 20877-2504 SN 0004-5756 J9 J ASSOC OFF ANA CHEM PD MAY-JUN PY 1991 VL 74 IS 3 BP 570 EP 571 PG 2 WC Chemistry, Analytical SC Chemistry GA FN229 UT WOS:A1991FN22900028 PM 1874705 ER PT J AU MOORE, JG CALK, LC AF MOORE, JG CALK, LC TI DEGASSING AND DIFFERENTIATION IN SUBGLACIAL VOLCANOS, ICELAND SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID VESICLES AB Within the neovolcanic zones of Iceland many volcanoes grew upward through icecaps that have subsequently melted. These steep-walled and flat-topped basaltic subglacial volcanoes, called tuyas, are composed of a lower sequence of subaqueously erupted, pillowed lavas overlain by breccias and hyaloclastites produced by phreatomagmatic explosions in shallow water, capped by a subaerially erupted lava plateau. Glass and whole-rock analyses of samples collected from six tuyas indicate systematic variations in major elements showing that the individual volcanoes are monogenetic, and that commonly the tholeiitic magmas differentiated and became more evolved through the course of the eruption that built the tuya. At Herdubreid, the most extensively studies tuya, the upward change in composition indicates that more than 50 wt.% of the first erupted lavas need crystallize over a range of 60-degrees-C to produce the last erupted lavas. The S content of glass commonly decreases upward in the tuyas from an average of about 0.08 wt.% at the base to < 0.02 wt.% in the subaerially erupted lava at the top, and is a measure of the depth of water (or ice) above the eruptive vent. The extensive subsurface crystallization that generates the more evolved, lower-temperature melts during the growth of the tuyas, apparently results from cooling and degassing of megma contained in shallow magma chambers and feeders beneath the volcanoes. Cooling may result from percolation of meltwater down cracks, vaporization, and cycling in a hydrothermal circulation. Degassing occurs when progressively lower pressure eruption (as the volcanic vent grows above the ice/water surface) lowers the volatile vapour pressure of subsurface melt, thus elevating the temperature of the liquids and hastening liquid-crystal differentiation. RP MOORE, JG (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 22 TC 34 Z9 34 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD MAY PY 1991 VL 46 IS 1-2 BP 157 EP 180 DI 10.1016/0377-0273(91)90081-A PG 24 WC Geosciences, Multidisciplinary SC Geology GA FP684 UT WOS:A1991FP68400010 ER PT J AU LANDING, WM BURNETT, WC LYONS, WB OREM, WH AF LANDING, WM BURNETT, WC LYONS, WB OREM, WH TI NUTRIENT CYCLING AND THE BIOGEOCHEMISTRY OF MANGANESE, IRON, AND ZINC IN JELLYFISH LAKE, PALAU SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID BLACK-SEA; TRACE-METALS; SULFIDE; WATERS; EQUILIBRIUM; SEAWATER; COPPER; OCEAN; FJORD AB The oxic waters in Jellyfish Lake, a stagnant marine lake in Palau, are depleted in NO3-, PO43-, dissolved Si, Mn, Fe, and Zn, while the underlying anoxic waters are significantly enriched in these species and NH3. NH3 and PO4(3-) regeneration and dissolved sulfide production in the anoxic zone yield a stoichiometry of C138N13P for organic matter undergoing recycling in the anoxic waters. In the anoxic zone, dissolved Mn, Fe, and Zn reach maximum concentrations of 30, 22, and 2.5 nM. The Fe concentrations are consistent with mackinawite or greigite solubility control. Mn approaches saturation with respect to haurite. Zn may be controlled by the solubility of ZnS coprecipitate. The sediments are enriched in Fe and depleted in Zn relative to Asian dust at Enewetak. A two-box model is used to calculate an eddy diffusion coefficient of 0.0015 cm2 s-1 across the chemocline. The upward diffusive loss of NH3 added to the sedimentation rate of N and multiplied by the stoichiometric C:N ratio yields an organic carbon flux into the anoxic waters of 1,200-mu-mol C cm-2 yr-1, which is approximately 13% of the total primary productivity. C1 UNIV NEW HAMPSHIRE,INST STUDY EARTH OCEANS & SPACE,DURHAM,NH 03824. US GEOL SURVEY,RESTON,VA 22092. RP LANDING, WM (reprint author), FLORIDA STATE UNIV,DEPT OCEANOG,B-169,TALLAHASSEE,FL 32306, USA. NR 26 TC 32 Z9 32 U1 0 U2 6 PU AMER SOC LIMNOLOGY OCEANOGRAPH PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD MAY PY 1991 VL 36 IS 3 BP 515 EP 525 PG 11 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA GB764 UT WOS:A1991GB76400009 ER PT J AU OREM, WH BURNETT, WC LANDING, WM LYONS, WB SHOWERS, W AF OREM, WH BURNETT, WC LANDING, WM LYONS, WB SHOWERS, W TI JELLYFISH LAKE, PALAU - EARLY DIAGENESIS OF ORGANIC-MATTER IN SEDIMENTS OF AN ANOXIC MARINE LAKE SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID FLORIDA EVERGLADES; SULFATE REDUCTION; PORE WATERS; C-13 NMR; CARBON; NITROGEN; SULFUR; ENVIRONMENTS; INDICATORS; BASIN AB Jellyfish Lake, a meromictic, marine lake in the Palau Islands, western Pacific Ocean, is accumulating organic matter-rich sediments (46% wt/wt) below anoxic, highly sulfide bottom water. Elemental and stable isotope (delta-C-13) data indicate that the sedimentary organic matter is primarily derived from vascular plant remains (65-90%) and would form a type 2 kerogen. A bacterial layer at the oxic-anoxic interface in the water column may play an important role in the rapid recycling of algal-derived organic matter from the highly productive surface waters. The major postdepositional change in the sedimentary organic matter is carbohydrate biodegradation, as shown by C-13 NMR. Lignin and aliphatic substances are preserved in the sediments. Dissolved organic matter in pore waters is primarily composed of carbohydrates, reflecting the degradation of sedimentary carbohydrates. Rate constants for organic carbon degradation and sulfate reduction in sediments of the lake are about 10x lower than in other anoxic sediments. This may reflect the vascular plant source and partly degraded nature of the organic matter reaching the sediments of the lake. Elemental results from sediment cores and stable isotope (delta-O-18, delta-C-13) studies of shells from the sediments indicate probable climatic or ecological fluctuations affecting the depositional environment of the lake between 80 and 110 yr ago. The high sedimentation rate and stable environment of Jellyfish Lake make it a possible environment for studies of climatic fluctuations during the Holocene. C1 FLORIDA STATE UNIV,DEPT OCEANOG,TALLAHASSEE,FL 32306. UNIV NEW HAMPSHIRE,INST STUDY EARTH OCEANS & SPACE,DURHAM,NH 03824. N CAROLINA STATE UNIV,DEPT MARINE EARTH & ATMOSPHER SCI,RALEIGH,NC 27650. RP OREM, WH (reprint author), US GEOL SURVEY,MS 923,RESTON,VA 22092, USA. NR 49 TC 25 Z9 26 U1 0 U2 9 PU AMER SOC LIMNOLOGY OCEANOGRAPH PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD MAY PY 1991 VL 36 IS 3 BP 526 EP 543 PG 18 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA GB764 UT WOS:A1991GB76400010 ER PT J AU MILLER, RL MCPHERSON, BF AF MILLER, RL MCPHERSON, BF TI ESTIMATING ESTUARINE FLUSHING AND RESIDENCE TIMES IN CHARLOTTE HARBOR, FLORIDA, VIA SALT BALANCE AND A BOX MODEL SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Note ID SCALES; EXCHANGE; BAY; SEA AB We present a new concept and techniques for processing flow and salinity data and calibrating a box model designed to estimate water residence times in Charlotte Harbor, a large estuary in southwestern Florida. The new concept is that, over many tidal cycles, the tidally averaged "flow" (Q(g)) of water from the Gulf of Mexico with a salinity of 35 parts per thousand can be treated as a constant at any point in the estuary. This flow is used in a simple mixing equation to predict salinity in the estuary at different river inflows, and the predicted salinities are used to compute residence times for water in the estuary. The techniques developed to achieve optimal precision in the relation between river inflow and salinity include a newly derived equation to fit Q(g) by a least-squares method and a procedure to determine the optimal averaging period for river inflow. Results from Charlotte Harbor indicate that, under average (70 m3 s-1) river inflow, 95% of the original water present in the harbor flushes into the gulf in 130 d. RP MILLER, RL (reprint author), US GEOL SURVEY,4710 EISENHOWER,BLVD B-5,TAMPA,FL 33634, USA. NR 20 TC 58 Z9 61 U1 0 U2 3 PU AMER SOC LIMNOLOGY OCEANOGRAPH PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD MAY PY 1991 VL 36 IS 3 BP 602 EP 612 PG 11 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA GB764 UT WOS:A1991GB76400019 ER PT J AU ORLOWSKI, LA GRUNDY, WD MIELKE, PW AF ORLOWSKI, LA GRUNDY, WD MIELKE, PW TI AN EMPIRICAL COVERAGE TEST FOR THE G-SAMPLE PROBLEM SO MATHEMATICAL GEOLOGY LA English DT Article DE MULTIPLE SAMPLE; NONPARAMETRIC; PERMUTATION TEST; UNIVARIATE-CONTINUOUS DATA AB A nonparametric g-sample empirical coverage test has recently been developed for univariate continuous data. It is based upon the empirical coverages which are spacings of multiple random samples. The test is capable of detecting any distributional differences which may exist among the parent populations, without additional assumptions beyond randomness and continuity. The test can be effective with the limited and/or unequal sample sizes most often encountered in geologic studies. A computer program for implementing this procedure, G-SECT 1, is available. C1 US GEOL SURVEY,DENVER,CO 80225. COLORADO STATE UNIV,DEPT STAT,FT COLLINS,CO 80523. RP ORLOWSKI, LA (reprint author), NP&P GEOSTAT,316 S GRANT AVE,FT COLLINS,CO 80521, USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0882-8121 J9 MATH GEOL JI Math. Geol. PD MAY PY 1991 VL 23 IS 4 BP 583 EP 589 DI 10.1007/BF02065808 PG 7 WC Geosciences, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Geology; Mathematics GA FQ566 UT WOS:A1991FQ56600005 ER PT J AU MILLER, GH WENDORF, F ERNST, R SCHILD, R CLOSE, AE FRIEDMAN, I SCHWARCZ, HP AF MILLER, GH WENDORF, F ERNST, R SCHILD, R CLOSE, AE FRIEDMAN, I SCHWARCZ, HP TI DATING LACUSTRINE EPISODES IN THE EASTERN SAHARA BY THE EPIMERIZATION OF ISOLEUCINE IN OSTRICH EGGSHELLS SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY LA English DT Article; Proceedings Paper CT CONF ON SALT LAKES, EVAPORITES AND AEOLIAN DEPOSITS CY AUG 08-16, 1988 CL ARKAROOLA, AUSTRALIA SP SALT LAKES EVAPORITES & AEOLIAN DEPOSITS PROGRAM ID FLUCTUATIONS; LEVEL; BP AB The eggshell of the African ostrich, Struthio camelus, closely approximates a closed system for the retention of indigenous proteinaceous residues. Epimerization of the protein amino acid isoleucine follows linear first-order kinetics in laboratory simulations nearly to racemic equilibrium, and the variation in D/L ratio within a single fragment, or between fragments of the same age, is significantly less than in other carbonate systems. These observations suggest that the extent of isoleucine epimerization (aIle/Ile ratio) in ostrich eggshell offers the potential for high-resolution geochronology of Quaternary deposits. From the simulation experiments, and dated early Holocene samples for which we have in situ mean annual sediment temperature measurements, Arrhenius parameters have been calculated; the activation energy is 30.33 kcal mol-1, similar to that of other carbonate systems. We have measured the aIle/Ile ratio in ostrich eggshell associate with lacustrine episodes at Bir Tarfawi and Bir Sahara East, two depressions in what is currently the hyperarid eastern Sahara. The ratios can be used directly to indicate qualitatively the time represented by each series of lake sediment, and to correlate disjunct lacustrine deposits within and between the basins. Uranium-series disequilibrium dating of algal mats contained within some of the lake beds indicate that a major wet interval occurred about 130 ka ago. Using the U-series date for calibration, the amino acids ratios are used to date the most recent lacustrine interval to about 100 ka B.P., and two older intervals, one about 200 +/- 25 ka B.P., and an older interval that occurred prior to 250 ka ago. C1 UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309. SO METHODIST UNIV,DEPT ANTHROPOL,DALLAS,TX 75275. US GEOL SURVEY,ISOTOPE GEOL BRANCH,DENVER,CO 80225. MCMASTER UNIV,DEPT GEOL,HAMILTON L8S 4M1,ONTARIO,CANADA. RP MILLER, GH (reprint author), UNIV COLORADO,INSTAAR,CTR GEOCHRONOL RES,BOULDER,CO 80309, USA. RI Ernst, Richard/I-1870-2016 NR 20 TC 29 Z9 29 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-0182 J9 PALAEOGEOGR PALAEOCL JI Paleogeogr. Paleoclimatol. Paleoecol. PD MAY PY 1991 VL 84 IS 1-4 BP 175 EP 189 DI 10.1016/0031-0182(91)90043-Q PG 15 WC Geography, Physical; Geosciences, Multidisciplinary; Paleontology SC Physical Geography; Geology; Paleontology GA FU238 UT WOS:A1991FU23800012 ER PT J AU SMOOT, JP AF SMOOT, JP TI SEDIMENTARY FACIES AND DEPOSITIONAL-ENVIRONMENTS OF EARLY MESOZOIC NEWARK SUPERGROUP BASINS, EASTERN NORTH-AMERICA SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY LA English DT Article; Proceedings Paper CT CONF ON SALT LAKES, EVAPORITES AND AEOLIAN DEPOSITS CY AUG 08-16, 1988 CL ARKAROOLA, AUSTRALIA SP SALT LAKES EVAPORITES & AEOLIAN DEPOSITS PROGRAM ID LATERITE DERIVATIVE FACIES; NOVA-SCOTIA; BLOMIDON REDBEDS; BERLIN FORMATION; HARTFORD BASIN; MAKHTESH-RAMON; ALLUVIAL-FAN; CLOSED-BASIN; FUNDY BASIN; RIFT-BASIN AB The early Mesozoic Newark Supergroup consists of continental sedimentary rocks and basalt flows that occupy a NE-trending belt of elongate basins exposed in eastern North America. The basins were filled over a period of 30-40 m.y. spanning the Late Triassic to Early Jurassic, prior to the opening of the north Atlantic Ocean. The sedimentary rocks are here divided into four principal lithofacies. The alluvial-fan facies includes deposits dominated by: (1) debris flows; (2) shallow braided streams; (3) deeper braided streams (with trough crossbeds); or (4) intense bioturbation or hyperconcentrated flows (tabular, unstratified muddy sandstone). The fluvial facies include deposits of: (1) shallow, ephemeral braided streams; (2) deeper, flash-flooding, braided streams (with poor sorting and crossbeds); (3) perennial braided rivers; (4) meandering rivers; (5) meandering streams (with high suspeded loads); (6) overbank areas or local flood-plain lakes; or (7) local streams and/or colluvium. The lacustrine facies includes deposits of: (1) deep perennial lakes; (2) shallow perennial lakes; (3) shallow ephemeral lakes; (4) playa dry mudflats; (5) salt-encrusted saline mudflats; or (6) vegetated mudflats. The lake margin clastic facies includes deposits of: (1) birdfoot deltas; (2) stacked Gilbert-type deltas; (3) sheet deltas; (4) wave-reworked alluvial fans; or (5) wave-sorted sand sheets. Coal deposits are present in the lake margin clastic and the lacustrine facies of Carnian age (Late Triassic) only in basins of south-central Virginia and North and South Carolina. Eolian deposits are known only from the basins in Nova Scotia and Connecticut. Evaporites (and their pseudomorphs) occur mainly in the northern basins as deposits of saline soils and less commonly of saline lakes, and some evaporite and alkaline minerals present in the Mesozoic rocks may be a result of later diagenesis. These relationships suggest climatic variations across paleolatitudes, more humid to the south where coal beds are preserved, and more arid in the north where evaporites and eolian deposits are common. Fluctuations in paleoclimate that caused lake levels to rise and fall in hydrologically closed basin are preserved as lacustrine cycles of various scales, including major shifts in the Late Triassic from a wet Carnian to an arid Norian. In contrast, fluvial deposits were mainly formed in response to the tectonic evolution of the basins, but to some extent also reflect climatic changes. The Newark Supergroup illustrates the complexity of rift-basin sedimentation and the problems that may arise from using a single modern analog for sedimentary deposition spanning millions of years. It also shows that a tremendous wealth of depositional, climatic, and tectonic information is preserved in ancient rift-basin deposits which can be recovered if the depositional processes of modern rift-basin deposits are understood. RP SMOOT, JP (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 159 TC 55 Z9 57 U1 2 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-0182 J9 PALAEOGEOGR PALAEOCL JI Paleogeogr. Paleoclimatol. Paleoecol. PD MAY PY 1991 VL 84 IS 1-4 BP 369 EP 423 DI 10.1016/0031-0182(91)90055-V PG 55 WC Geography, Physical; Geosciences, Multidisciplinary; Paleontology SC Physical Geography; Geology; Paleontology GA FU238 UT WOS:A1991FU23800024 ER PT J AU MEYER, CE SARNAWOJCICKI, AM HILLHOUSE, JW WOODWARD, MJ SLATE, JL SORG, DH AF MEYER, CE SARNAWOJCICKI, AM HILLHOUSE, JW WOODWARD, MJ SLATE, JL SORG, DH TI FISSION-TRACK AGE (400,000 YR) OF THE ROCKLAND TEPHRA, BASED ON INCLUSION OF ZIRCON GRAINS LACKING FOSSIL FISSION TRACKS SO QUATERNARY RESEARCH LA English DT Article ID CALIFORNIA; BISHOP; TUFF C1 STANFORD UNIV,STANFORD,CA 94305. UNIV COLORADO,BOULDER,CO 80309. RP MEYER, CE (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 24 TC 18 Z9 18 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD MAY PY 1991 VL 35 IS 3 BP 367 EP 382 DI 10.1016/0033-5894(91)90051-6 PG 16 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA FN358 UT WOS:A1991FN35800005 ER PT J AU HARDEN, JW TAYLOR, EM HILL, C MARK, RK MCFADDEN, LD REHEIS, MC SOWERS, JM WELLS, SG AF HARDEN, JW TAYLOR, EM HILL, C MARK, RK MCFADDEN, LD REHEIS, MC SOWERS, JM WELLS, SG TI RATES OF SOIL DEVELOPMENT FROM 4 SOIL CHRONOSEQUENCES IN THE SOUTHERN GREAT-BASIN SO QUATERNARY RESEARCH LA English DT Article ID QUATERNARY CLIMATIC CHANGES; CALIFORNIA; DESERT; CARBONATE; HOLOCENE; DEPOSITS; MOJAVE; FIELD C1 US GEOL SURVEY,DENVER,CO 80225. UNIV NEW MEXICO,DEPT GEOL,ALBUQUERQUE,NM 87131. RP HARDEN, JW (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 40 TC 54 Z9 55 U1 0 U2 11 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD MAY PY 1991 VL 35 IS 3 BP 383 EP 399 DI 10.1016/0033-5894(91)90052-7 PG 17 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA FN358 UT WOS:A1991FN35800006 ER PT J AU MILTON, NM EISWERTH, BA AGER, CM AF MILTON, NM EISWERTH, BA AGER, CM TI EFFECT OF PHOSPHORUS DEFICIENCY ON SPECTRAL REFLECTANCE AND MORPHOLOGY OF SOYBEAN PLANTS SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID EXPLORATION AB Soybean plants were grown in hydroponic solutions having three concentration levels of phosphorus. Spectral reflectance changes included higher reflectance in the green and yellow portions of the electromagnetic spectrum in phosphorus-deficient plants and a difference in position of the long wavelength edge (the red edge) of the chlorophyll absorption band centered near 0.68-mu-m. Plants having the least phosphorus in the growing medium did not show the normal shift of the red edge to longer wavelength which occurs as leaves mature. Shoot and root biomass were significantly lower in the phosphorus-deficient plants. These results are consistent with those obtained when soybean plants are dosed with elevated concentrations of metallic elements. We hypothesize that nutrient imbalances or anomalous metal concentrations in the soil set up physiological conditions at the soil / root interface that are responsible for the reflectance differences observed in laboratory and field studies of plants growing in substrates enriched in metallic elements. C1 US GEOL SURVEY,RESTON,VA 22092. NR 18 TC 37 Z9 55 U1 2 U2 10 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY PY 1991 VL 36 IS 2 BP 121 EP 127 DI 10.1016/0034-4257(91)90034-4 PG 7 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA FZ863 UT WOS:A1991FZ86300003 ER PT J AU CELEBI, M AF CELEBI, M TI TOPOGRAPHICAL AND GEOLOGICAL AMPLIFICATION - CASE-STUDIES AND ENGINEERING IMPLICATIONS SO STRUCTURAL SAFETY LA English DT Article; Proceedings Paper CT INTERNATIONAL WORKSHOP ON SPATIAL VARIATION OF EARTHQUAKE GROUND MOTION CY NOV 07-09, 1988 CL PRINCETON UNIV, DUNWALKE, NJ HO PRINCETON UNIV DE TOPOGRAPHY; GEOLOGY; AMPLIFICATION; EARTHQUAKES; BUILDING CODES; SPECTRAL RATIO; SEISMOGRAMS; SPECTRUM ID GROUND MOTION; EARTHQUAKE; MICHOACAN; MEXICO AB Topographical and geological amplification that occurred during past earthquakes are quantified using spectral ratios of recorded motions. Several cases are presented from the 1985 Chilean and Mexican earthquakes as well as the 1983 Coalinga (California) and 1987 Supersition Hills (California) earthquakes. The strong motions recorded in Mexico City during the 1985 Michoacan earthquake are supplemented by ambient motions recorded within Mexico City to quantify the now well known resonating frequencies of the Mexico City lakebed. Topographical amplification in Canal Beagle (Chile), Coalinga and Superstition Hills (California) are quantified using the ratios derived from the aftershocks following the earthquakes. A special dense array was deployed to record the aftershocks in each case. The implications of both geological and topographical amplification are discussed in light of current code provisions. The observed geological amplifications has already influenced the code provisions. Suggestions are made to the effect that the codes should include further provisions to take the amplification due to topography into account. RP CELEBI, M (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 14 TC 23 Z9 25 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-4730 J9 STRUCT SAF JI Struct. Saf. PD MAY PY 1991 VL 10 IS 1-3 BP 199 EP 217 DI 10.1016/0167-4730(91)90015-2 PG 19 WC Engineering, Civil SC Engineering GA FR103 UT WOS:A1991FR10300014 ER PT J AU MORIZOT, DC CALHOUN, SW CLEPPER, LL SCHMIDT, ME WILLIAMSON, JH CARMICHAEL, GJ AF MORIZOT, DC CALHOUN, SW CLEPPER, LL SCHMIDT, ME WILLIAMSON, JH CARMICHAEL, GJ TI MULTISPECIES HYBRIDIZATION AMONG NATIVE AND INTRODUCED CENTRARCHID BASSES IN CENTRAL TEXAS SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID LARGEMOUTH BASS; ELECTROPHORESIS; FISH AB Allele-frequency differences at 11 polymorphic protein loci provided discrete genetic markers with which to estimate the extent of hybridization among native and introduced centrarchid basses in central Texas streams. Native Guadalupe bass Micropterus treculi and northern largemouth bass M. salmoides salmoides now coexist with introduced Florida largemouth bass M. s. floridanus and smallmouth bass M. dolomieui in these streams. Interspecific hybridization was detected in three of four populations from the Blanco and San Marcos rivers, hybrids making up at least 31.8% of the individuals sampled. Complex hybridization patterns were evident, because F1, F2, and backcross hybrids were detected. At least one individual exhibited genetic markers of largemouth, smallmouth, and Guadalupe bass. Extensive multispecies hybridization threatens the survival of the endemic Guadalupe bass. C1 USDA ARS,CATFISH GENET RES UNIT,STONEVILLE,MS 38776. US FISH & WILDLIFE SERV,DENVER FED CTR,DENVER,CO 80225. RP MORIZOT, DC (reprint author), UNIV TEXAS,MD ANDERSON CANC CTR,DIV RES,SCI PK,POB 389,SMITHVILLE,TX 78957, USA. NR 24 TC 40 Z9 40 U1 4 U2 8 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 283 EP 289 DI 10.1577/1548-8659(1991)120<0283:MHANAI>2.3.CO;2 PG 7 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800002 ER PT J AU ELROD, JH OGORMAN, R AF ELROD, JH OGORMAN, R TI DIET OF JUVENILE LAKE TROUT IN SOUTHERN LAKE-ONTARIO IN RELATION TO ABUNDANCE AND SIZE OF PREY FISHES, 1979-1987 SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID SALVELINUS-NAMAYCUSH; MICHIGAN; DYNAMICS; GROWTH AB We examined the diet of juvenile lake trout Salvelinus namaycush (< 450 mm, total length) in Lake Ontario during four sampling periods (April-May, June, July-August, and October 1979-1987) in relation to changes in prey fish abundance in the depth zone where we caught the lake trout. Over all years combined, slimy sculpins Cottus cognatus contributed the most (39-52%) by wet weight to the diet, followed by alewives Alosa pseudoharengus (3-38%), rainbow smelt Osmerus mordax (17-43%), and johnny darters Etheostoma nigrum (2-10%). Over 90% of alewives eaten during April-May and June were age 1, and 98% of those eaten during October were age 0 (few alewives were eaten in July-August). Mean lengths of rainbow smelt and slimy sculpins in stomachs increased with size of lake trout. Juvenile lake trout generally fed opportunistically-seasonal and annual changes in diet usually reflected seasonal and annual changes in abundance of prey fishes near bottom where we captured the lake trout. Furthermore, diet within a given season varied with depth of capture of lake trout, and changes with depth in proportions of prey species in lake trout stomachs mirrored changes in proportions of the prey species in trawl catches at the same depth. Alewives (ages 0 and 1) were the only prey fish eaten in substantial quantities by both juvenile lake trout and other salmonines, and thus are a potential focus of competition between these predators. RP ELROD, JH (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,GREAT LAKES OSWEGO BIOL STN,17 LAKE ST,OSWEGO,NY 13126, USA. NR 14 TC 47 Z9 48 U1 2 U2 7 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 290 EP 302 DI 10.1577/1548-8659(1991)120<0290:DOJLTI>2.3.CO;2 PG 13 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800003 ER PT J AU RAHEL, FJ HUBERT, WA AF RAHEL, FJ HUBERT, WA TI FISH ASSEMBLAGES AND HABITAT GRADIENTS IN A ROCKY-MOUNTAIN GREAT-PLAINS STREAM - BIOTIC ZONATION AND ADDITIVE PATTERNS OF COMMUNITY CHANGE SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID RIVER CONTINUUM CONCEPT; ECOSYSTEM THEORY; LONGITUDINAL DISTRIBUTION; ENVIRONMENTAL GRADIENTS; SYSTEM; ORDER; ECOREGIONS; HEADWATER; OREGON AB We examined the importance of zonation and species additions in explaining longitudinal changes in the fish assemblage of a Rocky Mountain stream that descends onto the Great Plains of Wyoming. Community changes along an elevational gradient from 2,234 to 1,230 m above mean sea level reflected a combination of zonation and downstream addition of species. Zonation was evident on a broad spatial scale as a result of stream temperatures. A coldwater trout (Salmonidae) assemblage dominated headwater reaches but was replaced by a warmwater minnow-sucker (Cyprinidae-Catostomidae) assemblage below 2,000 m. Within the warmwater zone, fish community change was due mainly to the addition of new species downstream. Headwater sites were dominated by members of the insectivore feeding guild, and other trophic guilds were added downstream. The major gradient of habitat change downstream consisted of a decrease in pool habitat and increases in stream width, depth, current velocity, turbidity, and proportion of the channel consisting of run habitat. Minor gradients of of habitat change involved streambank condition and substrate particle size. Contrary to streams in forested regions, habitat diversity did not increase downstream, suggesting that increased living space and moderating environmental conditions contributed to the downstream increase in species richness. Local habitat modification due to cattle grazing or alterations in streamflow caused minor changes in fish assemblages but did not disrupt the dominant longitudinal patterns. Broad-scale zonation based on temperature regime and additive patterns within zones should typify other streams originating in montane regions. C1 UNIV WYOMING,US FISH & WILDLIFE SERV,WYOMING COOPERAT FISH & WILDLIFE RES UNIT,LARAMIE,WY 82071. RP RAHEL, FJ (reprint author), UNIV WYOMING,DEPT ZOOL & PHYSIOL,LARAMIE,WY 82071, USA. NR 57 TC 218 Z9 232 U1 8 U2 44 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 319 EP 332 DI 10.1577/1548-8659(1991)120<0319:FAAHGI>2.3.CO;2 PG 14 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800005 ER PT J AU MCADA, CW KAEDING, LR AF MCADA, CW KAEDING, LR TI MOVEMENTS OF ADULT COLORADO SQUAWFISH DURING THE SPAWNING SEASON IN THE UPPER COLORADO RIVER SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID PTYCHOCHEILUS-LUCIUS AB Colorado squawfish Ptychocheilus lucius spawned in widely separated areas throughout the 350-km section of the upper Colorado River upstream from Lake Powell, Utah, as evidenced by the movement of radio-tagged adults during the spawning season and the later capture of larvae. With one exception, tagged fish remained separated from each other during the spawning season. Distances moved by tagged fish were not related to fish size or location of initial capture along the river. Movements were generally shorter (mean, 23.2 km) than those reported for this species in the Green River basin, in part because of important habitat differences between the two rivers. Most tagged Colorado River fish were found near their initial point of capture after the spawning season. RP MCADA, CW (reprint author), US FISH & WILDLIFE SERV,COLORADO RIVER FISHERY PROJECT,529 25-1-2 RD,SUITE B-110,GRAND JUNCTION,CO 81505, USA. NR 15 TC 15 Z9 15 U1 0 U2 5 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 339 EP 345 DI 10.1577/1548-8659(1991)120<0339:MOACSD>2.3.CO;2 PG 7 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800007 ER PT J AU THOMPSON, JM BERGERSEN, EP CARLSON, CA KAEDING, LR AF THOMPSON, JM BERGERSEN, EP CARLSON, CA KAEDING, LR TI ROLE OF SIZE, CONDITION, AND LIPID-CONTENT IN THE OVERWINTER SURVIVAL OF AGE-O COLORADO SQUAWFISH SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID 1ST-YEAR SURVIVAL; LARGEMOUTH BASS; SMALLMOUTH BASS; FAT-CONTENT; MORTALITY; TEMPERATURE; WINTER; FISHES AB Small, medium, and large (mean total lengths of 30, 36, and 44 mm, respectively) hatchery-reared age-0 Colorado squawfish Ptychocheilus lucius were held at winter temperatures (3-5-degrees-C) in aquaria for 210 d to assess the role of size, condition factor, and lipid content on overwinter survival. Fish of each size-class were either fed dry pellets or starved. Fish in all size-classes fed at winter temperatures. The fish grew little, and condition declined as length of exposure to winter conditions increased. Condition declined more rapidly in starved than in fed fish of all size-classes. Lipid content of fish was inversely related to winter duration for all size-classes and feeding regimes. Percent survival at the end of 210 d was significantly lower in starved small (3.3%) and medium (6.7%) fish than in fed small (95.1%) and medium (98.4%) fish. Large fish showed 100% survival regardless of feeding regime. In years of large, prolonged runoff that delays the seasonal warming of the upper Colorado River, late spawning by Colorado squawfish leaves age-0 fish with only 2 months to grow and accumulate fat reserves before the onset of winter. These small age-0 fish may be unable to accumulate adequate lipid reserves to survive until the following spring. C1 COLORADO STATE UNIV,US FISH & WILDLIFE SERV,COLORADO COOPERAT FISH & WILDLIFE UNIT,FT COLLINS,CO 80523. NR 29 TC 94 Z9 95 U1 0 U2 10 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 346 EP 353 DI 10.1577/1548-8659(1991)120<0346:ROSCAL>2.3.CO;2 PG 8 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800008 ER PT J AU GRIFFIN, BR AF GRIFFIN, BR TI CHARACTERISTICS OF A CHONDROITIN AC LYASE PRODUCED BY CYTOPHAGA-COLUMNARIS SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article AB Cytophaga columnaris produces, in culture, an enzyme that degrades chondroitin sulfates A and C and hyaluronic acid, the complex polysaccharides of connective tissue. This study is the first to demonstrate production of such a tissue-degrading enzyme by this fish pathogen. Partial characterization of the enzyme has shown it to be of the chondroitin AC lyase type that has been described for some other bacteria. No relations were found between the host origin, geographic distribution, and amount of enzyme produced by the different isolates. The enzyme is constitutive, is released into the medium as it is produced, has a molecular weight estimated at 42,600, and has an optimum pH of 6.0. Kinetic studies indicate enzyme specificities in the order chondroitin sulfate A > chondroitin sulfate C > hyaluronic acid. The enzyme showed little or no reaction with chondroitin sulfate B and none with heparin, pectic acid, arabinogalactan, gum guar, or gum acacia. The enzyme was produced by all 16 C. columnaris isolates tested in the study but by none of the 13 isolates of non-columnaris, yellow-pigmented bacteria of aquatic origin. RP GRIFFIN, BR (reprint author), US FISH & WILDLIFE SERV,FISH FARMING EXPTL LAB,STUTTGART,AR 72160, USA. NR 22 TC 20 Z9 21 U1 0 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 1991 VL 120 IS 3 BP 391 EP 395 DI 10.1577/1548-8659(1991)120<0391:COACAL>2.3.CO;2 PG 5 WC Fisheries SC Fisheries GA FZ418 UT WOS:A1991FZ41800012 ER PT J AU DUVAL, JS AF DUVAL, JS TI POTASSIUM, URANIUM AND THORIUM GEOCHEMICAL MAPS OF THE CONTERMINOUS USA SO TRANSACTIONS OF THE INSTITUTION OF MINING AND METALLURGY SECTION B-APPLIED EARTH SCIENCE LA English DT Article; Proceedings Paper CT INTERNATIONAL GEOCHEMICAL MAPPING SESSIONS OF 28TH INTERNATIONAL GEOLOGICAL CONGRESS CY JUL, 1989 CL WASHINGTON, DC SP UNESCO, INT UNION GEOL SCI AB Geochemical maps showing the regional distributions of the near-surface concentrations of potassium, uranium and thorium have been compiled for the conterminous U.S.A. The maps are based on a compilation of the aerial gamma-ray surveys that were flown as part of the U.S. Department of Energy's National Uranium Resource Evaluation (NURE) programme. The NURE surveys were flown by various contractors and the resulting data sets were found to be inconsistent relative one with another. The techniques that were used to compile the data sets into a consistent database rely on the assumption that differences between or within surveys are the result of scaling or calibration errors. The compiled maps have many distinctive gamma-ray signatures, which are associated with known geological features. The Sandhills of north-central Nebraska and the Holocene deposits along the Mississippi River and some of its tributaries are among the more evident features of the maps. The Sandhills are characterized by low radioactivity with values less than 1.5% potassium, less than 1.5 ppm equivalent uranium (eU) and less than 6 ppm equivalent thorium (eTh). The Holocene deposits along the Mississippi River have higher concentrations of potassium and thorium (1-2% K and 6-10 ppm eTh) than the adjacent sediments (less than 0.9% K and less than 6 ppm eTh) through which the river flows. RP DUVAL, JS (reprint author), US GEOL SURVEY,GEOL BRANCH,DENVER,CO 80225, USA. NR 13 TC 0 Z9 0 U1 0 U2 2 PU INST MINING METALLURGY PI LONDON PA 44 PORTLAND PLACE, LONDON, ENGLAND W1N 4BR SN 0371-7453 J9 T I MIN METALL B JI Tran. Inst. Min. Metall. Sect. B-App. Earth Sci. PD MAY-AUG PY 1991 VL 100 BP B66 EP B73 PG 8 WC Geosciences, Multidisciplinary SC Geology GA GQ389 UT WOS:A1991GQ38900004 ER PT J AU PIRC, S MCNEAL, JM LENARCIC, T PROHIC, E SVRKOTA, R AF PIRC, S MCNEAL, JM LENARCIC, T PROHIC, E SVRKOTA, R TI GEOCHEMICAL MAPPING OF CARBONATE TERRAINS SO TRANSACTIONS OF THE INSTITUTION OF MINING AND METALLURGY SECTION B-APPLIED EARTH SCIENCE LA English DT Article; Proceedings Paper CT INTERNATIONAL GEOCHEMICAL MAPPING SESSIONS OF 28TH INTERNATIONAL GEOLOGICAL CONGRESS CY JUL, 1989 CL WASHINGTON, DC SP UNESCO, INT UNION GEOL SCI ID IDAHO AB Surface drainage samples, the usual media employed in mapping national territories, cannot be used for the geochemical mapping of carbonate terrains because of the absence of a regular surface-drainage pattern on karst. Suitable sampling media have been studied in Yugoslavia, one-third of which consists of karst terrain. Sampling designs for the work were based on analysis of variance techniques. During initial investigations of various sampling materials in northwest Yugoslavia sediment and aquatic moss from karst springs, along with soil, were established as the most appropriate media. Modified sampling procedures were then carefully applied along the entire Yugoslav karst belt, which includes terrains of contrasting topography, climate, pedology and vegetation. The studies indicate that climate and relief do not systematically influence the geochemical composition of soil. Regional and local variability was assessed for 21 chemical elements and the feasibility of producing stable regional geochemical maps was determined for a number of elements on the basis of sampling aquatic moss and sediment from karst springs and soil. C1 US GEOL SURVEY,ENVIRONM CHEM SECT,RESTON,VA 22092. ADELPHI UNIV,GARDEN CITY,NY 11530. RP PIRC, S (reprint author), EDVARD KARDELJ UNIV,GEOCHEM MINEAL & ECOM GEOL,YU-61000 LJUBLJANA,YUGOSLAVIA. NR 23 TC 2 Z9 2 U1 0 U2 1 PU INST MINING METALLURGY PI LONDON PA 44 PORTLAND PLACE, LONDON, ENGLAND W1N 4BR SN 0371-7453 J9 T I MIN METALL B JI Tran. Inst. Min. Metall. Sect. B-App. Earth Sci. PD MAY-AUG PY 1991 VL 100 BP B74 EP B87 PG 14 WC Geosciences, Multidisciplinary SC Geology GA GQ389 UT WOS:A1991GQ38900005 ER PT J AU HIRSCH, RM ALEXANDER, RB SMITH, RA AF HIRSCH, RM ALEXANDER, RB SMITH, RA TI SELECTION OF METHODS FOR THE DETECTION AND ESTIMATION OF TRENDS IN WATER-QUALITY SO WATER RESOURCES RESEARCH LA English DT Article ID STEP TRENDS AB One result of increased scientific and public interest in water quality over the past few decades has been the gradua accumulation of reliable long-term water quality data records and an interest in examining these data for long-term trends. This paper summarizes and examines some of the major issues and choices involved in detecting and estimating the magnitude of temporal trends in measures of stream water quality. The first issue is the type of trend hypothesis to examine: step trends versus monotonic trend. The second relates to the general category of statistical methods to employ: parametric versus nonparametric. The third issue relates to the kind of data to analyze: concentration data versus flux data. The fourth relates to issues of data manipulation to achieve the best results from the trend analysis. These issues include the use of mathematical transformations of the data and the removal of natural sources of variability in water quality due to seasonal and stream discharge variations. The final issue relates to the choice of a trend technique for the analysis of data records with censored or "less than" values. The authors' experiences during the past decade with the development of several trend detection techniques and application of these techniques to a large number of water quality records provide insight into the issues related to a choice of a statistical test for trend in water quality. RP HIRSCH, RM (reprint author), US GEOL SURVEY,MS 436,RESTON,VA 22092, USA. OI Hirsch, Robert/0000-0002-4534-075X NR 22 TC 237 Z9 246 U1 2 U2 32 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1991 VL 27 IS 5 BP 803 EP 813 DI 10.1029/91WR00259 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FK925 UT WOS:A1991FK92500015 ER PT J AU HERKELRATH, WN HAMBURG, SP MURPHY, F AF HERKELRATH, WN HAMBURG, SP MURPHY, F TI AUTOMATIC, REAL-TIME MONITORING OF SOIL-MOISTURE IN A REMOTE FIELD AREA WITH TIME DOMAIN REFLECTOMETRY SO WATER RESOURCES RESEARCH LA English DT Article ID WATER CONTENT; ELECTROMAGNETIC DETERMINATION; TRANSMISSION-LINES; TDR AB A multiplexing time domain reflectometry (TDR) system for real-time monitoring of volumetric soil moisture content was developed. The system was tested at a remote field site in the Hubbard Brook Experimental Forest in New Hampshire. The average value of soil moisture content in the top 500 mm of soil was measured every 4 hours for 1 year at 12 locations within a 12- by 18-m plot. The system functioned well except when the air temperature dropped below - 15-degrees-C, which caused the data logger tape recorder to stop. Calibrations run on undisturbed soil cores did not compare well with published curves developed for mineral soils, probably because of high soil organic matter content. The standard error of estimate of soil moisture content, indicated by the calibrations, was 0.02 cm3/cm3. The standard deviation of repeated moisture content measurements made in the field was 0.003 cm3/cm3. The effect of cable length on the TDR signal was investigated. It was found that long cables tend to attenuate the signal, ultimately making the measurement impractical. However, cable length had little effect on the calibration up to a length of 27 m. The coefficient of variation of the moisture content measurements taken at any given time ranged from 0.12 to 0.21 during the test period. As predicted by a stochastic analysis of soil moisture flow in heterogeneous soil, the spatial variability of the measurements decreased as average soil moisture increased. C1 UNIV KANSAS,ENVIRONM STUDIES PROGRAM,LAWRENCE,KS 66045. RP HERKELRATH, WN (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,345 MIDDLEFIELD RD,MS 496,MENLO PK,CA 94025, USA. NR 13 TC 191 Z9 206 U1 3 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1991 VL 27 IS 5 BP 857 EP 864 DI 10.1029/91WR00311 PG 8 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FK925 UT WOS:A1991FK92500020 ER PT J AU RITZI, RW SOROOSHIAN, S HSIEH, PA AF RITZI, RW SOROOSHIAN, S HSIEH, PA TI THE ESTIMATION OF FLUID-FLOW PROPERTIES FROM THE RESPONSE OF WATER LEVELS IN WELLS TO THE COMBINED ATMOSPHERIC AND EARTH TIDE FORCES SO WATER RESOURCES RESEARCH LA English DT Article ID PARAMETERS; UNIQUENESS AB The water level in an open well tapping a confined formation is influenced by natural forces including the solid Earth tide (SET) and atmospheric pressure variation (APV). The spectral method is used to analytically derive a model for well response to both random and periodic components of the combined SET and APV forcings (CSA). An inverse theory and algorithm are developed in order to provide improved results when using the model to estimate the hydraulic parameters associated with a given formation. An examination of the response surface of the estimation criterion reveals a uniqueness problem in estimating storativity (S). Since there is little correlation between the transmissivity (T) and S estimators, a good estimate for T is still possible independent of having accurate knowledge of S. An estimate of T is possible only if the data contain sufficient information so that the analysis occurs within an identifiability window. The CSA estimation methodology is compared to individual SET and APV schemes. The CSA scheme gives the greatest probability that sufficient information is contained in a data record so that T is indeed indentifiable. The results of applications to synthetic data indicate that the CSA scheme gives a T estimate with the most precision and also that it requires collecting fewer observations. These results are discussed in light of practical considerations when designing data collection procedures. C1 US GEOL SURVEY,MENLO PK,CA 94025. WRIGHT STATE UNIV,DEPT GEOL SCI,DAYTON,OH 45435. UNIV ARIZONA,DEPT HYDROL & WATER RESOURCES,TUCSON,AZ 85721. RP RITZI, RW (reprint author), WRIGHT STATE UNIV,DEPT GEOL SCI,DAYTON,OH 45435, USA. RI sorooshian, soroosh/B-3753-2008 OI sorooshian, soroosh/0000-0001-7774-5113 NR 18 TC 28 Z9 28 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1991 VL 27 IS 5 BP 883 EP 893 DI 10.1029/91WR00070 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FK925 UT WOS:A1991FK92500023 ER PT J AU LEBLANC, DR GARABEDIAN, SP HESS, KM GELHAR, LW QUADRI, RD STOLLENWERK, KG WOOD, WW AF LEBLANC, DR GARABEDIAN, SP HESS, KM GELHAR, LW QUADRI, RD STOLLENWERK, KG WOOD, WW TI LARGE-SCALE NATURAL GRADIENT TRACER TEST IN SAND AND GRAVEL, CAPE-COD, MASSACHUSETTS .1. EXPERIMENTAL-DESIGN AND OBSERVED TRACER MOVEMENT SO WATER RESOURCES RESEARCH LA English DT Article ID SOLUTE TRANSPORT; HYDRAULIC CONDUCTIVITY; GROUNDWATER-FLOW; DISPERSION; AQUIFERS; CONTAMINANTS; MIGRATION; LANDFILL AB A large-scale natural gradient tracer experiment was conducted on Cape Cod, Massachusetts, to examine the transport and dispersion of solutes in a sand and gravel aquifer. The nonreactive tracer, bromide, and the reactive tracers, lithium and molybdate, were injected as a pulse in July 1985 and monitored in three dimensions as they moved as far as 280 m down-gradient through an array of multilevel samplers. The bromide cloud moved horizontally at a rate of 0.42 m per day. It also moved downward about 4 m because of density-induced sinking early in the test and accretion of areal recharge from precipitation. After 200 m of transport, the bromide cloud had spread more than 80 m in the direction of flow, but was only 14 m wide and 4-6 m thick. The lithium and molybdate clouds followed the same path as the bromide cloud, but their rates of movement were retarded about 50% relative to bromide movement because of sorption onto the sediments. C1 MIT,DEPT REAKTORENTWICKLUNG,CAMBRIDGE,MA 02139. US GEOL SURVEY,RESTON,VA 22092. US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. RP LEBLANC, DR (reprint author), US GEOL SURVEY,28 LORD RD,SUITE 280,MARLBOROUGH,MA 01752, USA. RI Gelhar, Lynn/F-9139-2011 OI Gelhar, Lynn/0000-0001-6697-8552 NR 48 TC 380 Z9 383 U1 4 U2 53 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1991 VL 27 IS 5 BP 895 EP 910 DI 10.1029/91WR00241 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FK925 UT WOS:A1991FK92500024 ER PT J AU GARABEDIAN, SP LEBLANC, DR GELHAR, LW CELIA, MA AF GARABEDIAN, SP LEBLANC, DR GELHAR, LW CELIA, MA TI LARGE-SCALE NATURAL GRADIENT TRACER TEST IN SAND AND GRAVEL, CAPE-COD, MASSACHUSETTS .2. ANALYSIS OF SPATIAL MOMENTS FOR A NONREACTIVE TRACER SO WATER RESOURCES RESEARCH LA English DT Article ID SOLUTE TRANSPORT; STOCHASTIC-ANALYSIS; POROUS-MEDIA; MACROSCOPIC DISPERSION; GROUNDWATER-FLOW; AQUIFER; MACRODISPERSION AB A large-scale natural gradient tracer test was conducted to examine the transport of reactive and nonreactive tracers in a sand and gravel aquifer on Cape Cod, Massachusetts. As part of this test the transport of bromide, a nonreactive tracer, was monitored for about 280 m and quantified using spatial moments. The calculated mass of bromide for each sampling date varied between 85% and 105% of the injected mass using an estimated porosity of 0.39, and the center of mass moved at a nearly constant horizontal velocity of 0.42 m per day. A nonlinear change in the bromide longitudinal variance was observed during the first 26 m of travel distance, but afterward the variance followed a linear trend, indicating the longitudinal dispersivity had reached a constant value of 0.96 m. The transverse dispersivities were much smaller; transverse horizontal dispersivity was 1.8 cm, and transverse vertical dispersivity was about 1.5 mm. C1 MIT,RALPH M PARSONS LAB,DEPT CIVIL ENGN,CAMBRIDGE,MA 02139. RP GARABEDIAN, SP (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,28 LORD RD,SUITE 280,MARLBOROUGH,MA 01752, USA. RI Gelhar, Lynn/F-9139-2011 OI Gelhar, Lynn/0000-0001-6697-8552 NR 37 TC 315 Z9 317 U1 2 U2 27 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1991 VL 27 IS 5 BP 911 EP 924 DI 10.1029/91WR00242 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FK925 UT WOS:A1991FK92500025 ER PT J AU KNOPMAN, DS VOSS, CI GARABEDIAN, SP AF KNOPMAN, DS VOSS, CI GARABEDIAN, SP TI SAMPLING DESIGN FOR GROUNDWATER SOLUTE TRANSPORT - TESTS OF METHODS AND ANALYSIS OF CAPE-COD TRACER TEST DATA SO WATER RESOURCES RESEARCH LA English DT Article ID PARAMETER-ESTIMATION; SENSITIVITIES; MODELS AB Tests of a one-dimensional sampling design methodology on measurements of bromide concentration collected during the natural gradient tracer test conducted by the U.S. Geological Survey on Cape Cod, Massachusetts, demonstrate its efficacy for field studies of solute transport in groundwater and the utility of one-dimensional analysis. The methodology was applied to design of sparse two-dimensional networks of fully screened wells typical of those often used in engineering practice. In one-dimensional analysis, designs consist of the downstream distances to rows of wells oriented perpendicular to the groundwater flow direction and the timing of sampling to be carried out on each row. The power of a sampling design is measured by its effectiveness in simultaneously meeting objectives of model discrimination, parameter estimation, and cost minimization. One-dimensional models of solute transport, differing in processes affecting the solute and assumptions about the structure of the flow field, were considered for description of tracer cloud migration. When fitting each model using nonlinear regression, additive and multiplicative error forms were allowed for the residuals which consist of both random and model errors. The one-dimensional single-layer model of a nonreactive solute with multiplicative error was judged to be the best of those tested. Results show the efficacy of the methodology in designing sparse but powerful sampling networks. Designs that sample five rows of wells at five or fewer times in any given row performed as well for model discrimination as the full set of samples taken up to eight times in a given row from as many as 89 rows. Also, designs for parameter estimation judgded to be good by the methodology were as effective in reducing the variance of parameter estimates as arbitrary designs with many more samples. Results further showed that estimates of velocity and longitudinal dispersivity in one-dimensional models based on data from only five rows of fully screened wells each sampled five or fewer times were practically equivalent to values determined from moments analysis of the complete three-dimensional set of 29,285 samples taken during 16 sampling times. C1 US GEOL SURVEY,DIV WATER RESOURCES,MARLBOROUGH,MA 01752. RP KNOPMAN, DS (reprint author), US GEOL SURVEY,MAIL STOP 410,RESTON,VA 22092, USA. NR 21 TC 34 Z9 35 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1991 VL 27 IS 5 BP 925 EP 949 DI 10.1029/90WR02657 PG 25 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FK925 UT WOS:A1991FK92500026 ER PT J AU BATEMAN, PC AF BATEMAN, PC TI THE NATURE AND ORIGIN OF CORDILLERAN MAGMATISM - ANDERSON,JL SO SCIENCE LA English DT Book Review RP BATEMAN, PC (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 26 PY 1991 VL 252 IS 5005 BP 589 EP 590 DI 10.1126/science.252.5005.589-a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FJ127 UT WOS:A1991FJ12700056 PM 17838491 ER PT J AU VOIGHT, B CORNELIUS, RR AF VOIGHT, B CORNELIUS, RR TI PROSPECTS FOR ERUPTION PREDICTION IN NEAR REAL-TIME SO NATURE LA English DT Article ID MOUNT ST-HELENS AB THE 'materials science' method for eruption prediction 1-3 arises from the application of a general law governing the failure of materials: OMEGA-alpha OMEGA - A = 0, where A and alpha are empirical constants, and OMEGA is an observable quantity such as ground deformation, seismicity or gas emission. This law leads to the idea of the 'inverse-rate' plot, in which the time of failure can be estimated by extrapolation of the curve of OMEGA-1 versus time to a pre-determined intercept. Here we suggest that this method can be combined with real-time seismic amplitude monitoring to provide a tool for near-real-time eruption prediction, and we demonstrate how it might have been used to predict two dome-growth episodes at Mount St Helens volcano in 1985 and 1986, and two explosive eruptions at Redoubt volcano in 1989-90. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP VOIGHT, B (reprint author), PENN STATE UNIV,COLL EARTH & MINERAL SCI,UNIVERSITY PK,PA 16802, USA. NR 20 TC 64 Z9 64 U1 0 U2 4 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 25 PY 1991 VL 350 IS 6320 BP 695 EP 698 DI 10.1038/350695a0 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FJ130 UT WOS:A1991FJ13000056 ER PT J AU RALLS, K BROWNELL, RL AF RALLS, K BROWNELL, RL TI ZOOLOGY - A WHALE OF A NEW SPECIES SO NATURE LA English DT Editorial Material ID BEAKED WHALE; MESOPLODON C1 US FISH & WILDLIFE SERV,SAN SIMEON,CA 93452. RP RALLS, K (reprint author), SMITHSONIAN INST,NATL ZOOL PK,WASHINGTON,DC 20008, USA. NR 6 TC 2 Z9 2 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD APR 18 PY 1991 VL 350 IS 6319 BP 560 EP 560 DI 10.1038/350560a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FH112 UT WOS:A1991FH11200035 ER PT J AU MORRIS, SC SAVOY, LE HARRIS, AG AF MORRIS, SC SAVOY, LE HARRIS, AG TI AN ENIGMATIC ORGANISM FROM THE EXSHAW FORMATION (DEVONIAN-CARBONIFEROUS), ALBERTA, CANADA SO LETHAIA LA English DT Article ID CHONDROPHORINE HYDROZOA; COELENTERATE; VELELLIDAE; ORDOVICIAN; OCEANS; SHALES; WATER; ROCKS AB Libodiscus ascitus gen. et sp. nov. (incertae sedis) consists of a flask-like body (mean length of 15 mm; mean maximum width of 9 mm) bearing a flange of plates or flattened tentacles. At one end a pair of arm-like extensions connects with a disc with concentric markings. The flask has transverse structures with prominent relief. Some of these are more or less regularly arranged, but in other specimens they are much more irregular. On what appears to be the inner wall of the flask there are closely spaced striations. Libodiscus is known only from Devonian-Carboniferous transitional strata ('Exshaw' Formation) at Crowsnest Pass, southwest Alberta, Canada. Its affinities are speculative and no secure relationship can be demonstrated with metazoans, plants or other problematica such as chitinozoans. The disc is, however, similar to a number of discoidal fossils that previously have been assigned to chondrophorine medusoid hydrozoans. C1 US GEOL SURVEY,RESTON,VA 22092. MT HOLYOKE COLL,DEPT GEOG & GEOL,S HADLEY,MA 01075. RP MORRIS, SC (reprint author), UNIV CAMBRIDGE,DEPT EARTH SCI,CAMBRIDGE CB2 3EQ,ENGLAND. NR 48 TC 8 Z9 8 U1 2 U2 3 PU SCANDINAVIAN UNIVERSITY PRESS PI OSLO PA PO BOX 2959 TOYEN, JOURNAL DIVISION CUSTOMER SERVICE, N-0608 OSLO, NORWAY SN 0024-1164 J9 LETHAIA JI Lethaia PD APR 15 PY 1991 VL 24 IS 2 BP 139 EP 152 DI 10.1111/j.1502-3931.1991.tb01462.x PG 14 WC Paleontology SC Paleontology GA FL674 UT WOS:A1991FL67400004 ER PT J AU SIMMONS, KR CIESLEWICZ, PG SCHREIBER, RK VILLELLA, R AF SIMMONS, KR CIESLEWICZ, PG SCHREIBER, RK VILLELLA, R TI USE OF A WATER-POWERED DOSER TO LIME A REMOTE MASSACHUSETTS STREAM SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US FISH & WILDLIFE SERV,NFRC LEETOWN,KEARNEYSVILLE,WV 25430. UNIV MASSACHUSETTS,MCFWRU,DEPT FORESTRY & WILDLIFE,AMHERST,MA 01003. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 3 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301386 ER PT J AU GARRISON, PJ ROSE, W WATRAS, CJ HURLEY, JP AF GARRISON, PJ ROSE, W WATRAS, CJ HURLEY, JP TI MITIGATION OF ACID-RAIN BY GROUNDWATER ADDITION - AN ALTERNATIVE TO LIMING SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 WISCONSIN DEPT NAT RESOURCES,FITCHBURG,WI 53711. US GEOL SURVEY,MADISON,WI 53719. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 7 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301390 ER PT J AU MCKNIGHT, DM AIKEN, GR AF MCKNIGHT, DM AIKEN, GR TI PROCESSES INFLUENCING THE CHEMISTRY OF HUMIC SUBSTANCES IN FRESH AND MARINE WATERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER FED CTR,DIV WATER RESOURCES,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 14 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301676 ER PT J AU GOOLSBY, DA THURMAN, EM POMES, ML MAJURE, JJ AF GOOLSBY, DA THURMAN, EM POMES, ML MAJURE, JJ TI HERBICIDES IN ATMOSPHERIC WET DEPOSITION IN THE UPPER MIDWEST AND NORTHEAST UNITED-STATES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,WRD,DENVER,CO 80225. US GEOL SURVEY,WRD,LAWRENCE,KS 66049. US GEOL SURVEY,WRD,IOWA CITY,IA 52244. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 17 EP AGRO PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89300097 ER PT J AU MILLER, LG OREMLAND, RS CULBERTSON, CW AF MILLER, LG OREMLAND, RS CULBERTSON, CW TI COMPARATIVE BIOGEOCHEMISTRY OF 3 ALKALINE, SALINE LAKES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,MENLO PK,CA 94025. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 21 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301683 ER PT J AU KENT, DB REA, BA LEBLANC, D DAVIS, JA AF KENT, DB REA, BA LEBLANC, D DAVIS, JA TI MOBILITY OF ZN IN A SHALLOW, SAND AND GRAVEL AQUIFER CONTAMINATED BY SEWAGE EFFLUENT SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,MENLO PK,CA 94025. US GEOL SURVEY,MARLBOROUGH,MA 01752. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 39 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301422 ER PT J AU MORRISON, JF SIMON, NS GIRARD, JE AF MORRISON, JF SIMON, NS GIRARD, JE TI ISOLATION OF NATURAL AND ANTHROPOGENIC ORGANIC-COMPOUNDS FROM ESTUARINE BED SEDIMENTS USING SUPERCRITICAL FLUID EXTRACTION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 AMERICAN UNIV,DEPT CHEM,WASHINGTON,DC 20016. US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 42 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301425 ER PT J AU ECHOLS, KR SCHWARTZ, TR GALE, RW SCHMITT, CJ AF ECHOLS, KR SCHWARTZ, TR GALE, RW SCHMITT, CJ TI COMPARISON OF POLYCHLORINATED BIPHENYL RESIDUE PATTERNS IN FISH FROM SELECTED GREAT-LAKES AND LAKE SISKIWIT SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,COLUMBIA,MO 65201. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 46 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301429 ER PT J AU SIMON, NS MORRISON, JF AF SIMON, NS MORRISON, JF TI METALLOORGANIC COMPOUNDS EXTRACTED FROM ESTUARINE SUSPENDED ORGANIC MATERIAL AND BED SEDIMENTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. AMERICAN UNIV,DEPT CHEM,WASHINGTON,DC 20016. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 49 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301711 ER PT J AU KRABBENHOFT, DP BOWSER, CJ GAT, JR KENDALL, C AF KRABBENHOFT, DP BOWSER, CJ GAT, JR KENDALL, C TI STABLE ISOTOPE TECHNIQUES IN LAKE HYDROLOGY SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US FOREST SERV,MADISON,WI 53705. UNIV WISCONSIN,DEPT GEOL & GEOPHYS,MADISON,WI 53706. WEIZMANN INST SCI,IL-76100 REHOVOT,ISRAEL. US GEOL SURVEY,MENLO PK,CA 94025. NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 51 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301434 ER PT J AU OREMLAND, RS AF OREMLAND, RS TI OXIDATIVE DEMETHYLATION OF MONOMETHYLMERCURY IN SEDIMENTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,MENLO PK,CA 94025. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 51 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301713 ER PT J AU BAEDECKER, MJ AF BAEDECKER, MJ TI PARTITIONING AND TRANSPORT OF HYDROCARBONS FROM CRUDE-OIL IN A SAND AND GRAVEL AQUIFER SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. SO CALIF COASTAL WATER RES PROJECT,LONG BEACH,CA 90806. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 75 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301458 ER PT J AU DAVIS, JA KENT, DB ANDERSON, LCD WAITE, TD AF DAVIS, JA KENT, DB ANDERSON, LCD WAITE, TD TI CHEMICAL PROCESSES AFFECTING THE TRANSPORT OF CR(VI) IN GROUNDWATER SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 AUSTRALIAN NUCL SCI & TECHNOL ORGANISAT,SUTHERLAND,NSW,AUSTRALIA. US GEOL SURVEY,MENLO PK,CA 94025. RI Waite, T. David/A-1400-2008 OI Waite, T. David/0000-0002-5411-3233 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 80 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301463 ER PT J AU CLEVELAND, JM MULLIN, AH AF CLEVELAND, JM MULLIN, AH TI SPECIATION OF PLUTONIUM IN GROUND-WATER OF THE IDAHO NATIONAL ENGINEERING LABORATORY (INEL) SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER FED CTR,DIV WATER RESOURCES,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 84 EP NUCL PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG894 UT WOS:A1991FG89400083 ER PT J AU LEENHEER, JA AF LEENHEER, JA TI CHEMISTRY OF DISSOLVED ORGANIC-MATTER IN RIVERS, LAKES, AND RESERVOIRS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 89 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301472 ER PT J AU HURLEY, JP BABIARZ, CL KRABBENHOFT, DP ANDREN, AW AF HURLEY, JP BABIARZ, CL KRABBENHOFT, DP ANDREN, AW TI CYCLING PROCESSES OF MERCURY ACROSS SEDIMENT WATER INTERFACES IN SEEPAGE LAKES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 WISCONSIN DEPT NAT RESOURCES,BUR RES,FITCHBURG,WI 53711. UNIV WISCONSIN,WATER CHEM PROGRAM,MADISON,WI 53706. US GEOL SURVEY,MADISON,WI 53719. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 14 PY 1991 VL 201 BP 93 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA FG893 UT WOS:A1991FG89301476 ER PT J AU KIRBY, SH DURHAM, WB STERN, LA AF KIRBY, SH DURHAM, WB STERN, LA TI MANTLE PHASE-CHANGES AND DEEP-EARTHQUAKE FAULTING IN SUBDUCTING LITHOSPHERE SO SCIENCE LA English DT Review ID OLIVINE-SPINEL TRANSFORMATION; MOMENT TENSOR SOLUTIONS; FOCUS EARTHQUAKES; SYSTEM MG2SIO4-FE2SIO4; DESCENDING LITHOSPHERE; HIGH-PRESSURE; ISLAND ARCS; SLAB PENETRATION; POSTSPINEL TRANSFORMATIONS; GEOPHYSICAL IMPLICATIONS AB Inclined zones of earthquakes are the primary expression of lithosphere subduction. A distinct deep population of subduction-zone earthquakes occurs at depths of 350 to 690 kilometers. At those depths ordinary brittle fracture and frictional sliding, the faulting processes of shallow earthquakes, are not expected. A fresh understanding of these deep earthquakes comes from developments in several areas of experimental and theoretical geophysics, including the discovery and characterization of transformational faulting, a shear instability connected with localized phase transformations under nonhydrostatic stress. These developments support the hypothesis that deep earthquakes represent transformational faulting in a wedge of olivine-rich peridotite that is likely to persist metastably in coldest plate interiors to depths as great as 690 km. Predictions based on this deep structure of mantle phase changes are consistent with the global depth distribution of deep earthquakes, the maximum depths of earthquakes in individual subductions zones, and key source characteristics of deep events. C1 UNIV CALIF LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI,EXPTL GEOPHYS GRP,LIVERMORE,CA 94550. RP KIRBY, SH (reprint author), US GEOL SURVEY,TECTONOPHYS BRANCH,MAIL STOP 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 191 TC 269 Z9 278 U1 7 U2 33 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 12 PY 1991 VL 252 IS 5003 BP 216 EP 225 DI 10.1126/science.252.5003.216 PG 10 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FG036 UT WOS:A1991FG03600034 PM 17769266 ER PT J AU SAUNDERS, RS ARVIDSON, RE HEAD, JW SCHABER, GG STOFAN, ER SOLOMON, SC AF SAUNDERS, RS ARVIDSON, RE HEAD, JW SCHABER, GG STOFAN, ER SOLOMON, SC TI AN OVERVIEW OF VENUS GEOLOGY SO SCIENCE LA English DT Article ID BETA-REGIO; VENERA-16 DATA; RADAR IMAGES; SURFACE; VOLCANISM; STYLES AB The Magellan spacecraft is producing comprehensive image and altimetry data for the planet Venus. Initial geologic mapping of the planet reveals a surface dominated by volcanic plains and characterized by extensive volcanism and tectonic deformation. Geologic and geomorphologic units include plains terrains, tectonic terrains, and surficial material units. Understanding the origin of these units and the relation between them is an ongoing task of the Magellan team. C1 WASHINGTON UNIV,DEPT EARTH & PLANETARY SCI,ST LOUIS,MO 63130. MIT,DEPT EARTH ATMOSPHER & PLANETARY SCI,CAMBRIDGE,MA 02139. BROWN UNIV,DEPT GEOL SCI,PROVIDENCE,RI 02912. US GEOL SURVEY,FLAGSTAFF,AZ 86001. RP SAUNDERS, RS (reprint author), CALTECH,JET PROP LAB,PASADENA,CA 91109, USA. NR 36 TC 31 Z9 31 U1 0 U2 8 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 12 PY 1991 VL 252 IS 5003 BP 249 EP 252 DI 10.1126/science.252.5003.249 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FG036 UT WOS:A1991FG03600039 PM 17769270 ER PT J AU PETTENGILL, GH FORD, PG JOHNSON, WTK RANEY, RK SODERBLOM, LA AF PETTENGILL, GH FORD, PG JOHNSON, WTK RANEY, RK SODERBLOM, LA TI MAGELLAN - RADAR PERFORMANCE AND DATA PRODUCTS SO SCIENCE LA English DT Article AB The Magellan Venus orbiter carries only one scientific instrument: a 12.6-centimeter-wavelength radar system shared among three data-taking modes. The synthetic-aperture mode images radar echoes from the Venus surface at a resolution of between 120 and 300 meters, depending on spacecraft altitude. In the altimetric mode, relative height measurement accuracies may approach 5 meters, depending on the terrain's roughness, although orbital uncertainties place a floor of about 50 meters on the absolute uncertainty. In areas of extremely rough topography, accuracy is limited by the inherent line-of-sight radar resolution of about 88 meters. The maximum elevation observed to date, corresponding to a planetary radius of 6062 kilometers, lies within Maxwell Mons. When used as a thermal emission radiometer, the system can determine surface emissivities to an absolute accuracy of about 0.02. Mosaicked and archival digital data products will be released in compact disk (CDROM) format. C1 CANADA CTR REMOTE SENSING,OTTAWA K1A 0Y7,ONTARIO,CANADA. CALTECH,JET PROP LAB,PASADENA,CA 91109. US GEOL SURVEY,FLAGSTAFF,AZ 86001. RP PETTENGILL, GH (reprint author), MIT,CAMBRIDGE,MA 02139, USA. NR 7 TC 87 Z9 87 U1 0 U2 7 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 12 PY 1991 VL 252 IS 5003 BP 260 EP 265 DI 10.1126/science.252.5003.260 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FG036 UT WOS:A1991FG03600041 PM 17769272 ER PT J AU HEAD, JW CAMPBELL, DB ELACHI, C GUEST, JE MCKENZIE, DP SAUNDERS, RS SCHABER, GG SCHUBERT, G AF HEAD, JW CAMPBELL, DB ELACHI, C GUEST, JE MCKENZIE, DP SAUNDERS, RS SCHABER, GG SCHUBERT, G TI VENUS VOLCANISM - INITIAL ANALYSIS FROM MAGELLAN DATA SO SCIENCE LA English DT Article ID FLOW; EMPLACEMENT AB Magellan images confirm that volcanism is widespread and has been fundamentally important in the formation and evolution of the crust of Venus. High-resolution imaging data reveal evidence for intrusion (dike formation and cryptodomes) and extrusion (a wide range of lava flows). Also observed are thousands of small shield volcanoes, larger edifices up to several hundred kilometers in diameter, massive outpourings of lavas, and local pyroclastic deposits. Although most features are consistent with basaltic compositions, a number of large pancake-like domes are morphologically similar to rhyolite-dacite domes on Earth. Flows and sinuous channels with lengths of many hundreds of kilometers suggest that extremely high effusion rates or very fluid magmas (perhaps komatiites) may be present. Volcanism is evident in various tectonic settings (coronae, linear extensional and compressional zones, mountain belts, upland rises, highland plateaus, and tesserae). Volcanic resurfacing rates appear to be low (less than 2 km3/yr) but the significance of dike formation and intrusions, and the mode of crustal formation and loss remain to be established. C1 UCL, UNIV LONDON OBSERV, LONDON NW7 2QS, ENGLAND. UNIV CAMBRIDGE, DEPT EARTH SCI, CAMBRIDGE CB3 0EZ, ENGLAND. CORNELL UNIV, DEPT ASTRON, ITHACA, NY 14853 USA. CALTECH, JET PROP LAB, PASADENA, CA 91109 USA. US GEOL SURVEY, FLAGSTAFF, AZ 86001 USA. UNIV CALIF LOS ANGELES, INST GEOPHYS & PLANETARY PHYS, DEPT EARTH & SPACE SCI, LOS ANGELES, CA 90024 USA. RP HEAD, JW (reprint author), BROWN UNIV, DEPT GEOL SCI, PROVIDENCE, RI 02912 USA. NR 82 TC 94 Z9 94 U1 0 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD APR 12 PY 1991 VL 252 IS 5003 BP 276 EP 288 DI 10.1126/science.252.5003.276 PG 13 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FG036 UT WOS:A1991FG03600044 PM 17769275 ER PT J AU PHILLIPS, RJ ARVIDSON, RE BOYCE, JM CAMPBELL, DB GUEST, JE SCHABER, GG SODERBLOM, LA AF PHILLIPS, RJ ARVIDSON, RE BOYCE, JM CAMPBELL, DB GUEST, JE SCHABER, GG SODERBLOM, LA TI IMPACT CRATERS ON VENUS - INITIAL ANALYSIS FROM MAGELLAN SO SCIENCE LA English DT Article ID VENERA-16 SPACECRAFT; RADAR IMAGES; CONTINUATION; RATES AB Magellan radar images of 15 percent of the planet show 135 craters of probable impact origin. Craters more than 15 km across tend to contain central peaks, multiple central peaks, and peak rings. Many craters smaller than 15 km exhibit multiple floors or appear in clusters; these phenomena are attributed to atmospheric breakup of incoming meteoroids. Additionally, the atmosphere appears to have prevented the formation of primary impact craters smaller than about 3 km and produced a deficiency in the number of craters smaller than about 25 km across. Ejecta is found at greater distances than that predicted by simple ballistic emplacement, and the distal ends of some ejecta deposits are lobate. These characteristics may represent surface flows of material initially entrained in the atmosphere. Many craters are surrounded by zones of low radar albedo whose origin may have been deformation of the surface by the shock or pressure wave associated with the incoming meteoroid. Craters are absent from several large areas such as a 5 million square kilometer region around Sappho Patera, where the most likely explanation for the dearth of craters is volcanic resurfacing. There is apparently a spectrum of surface ages on Venus ranging approximately from 0 to 800 million years, and therefore Venus must be a geologically active planet. C1 UNIV LONDON OBSERV,LONDON NW7 2QS,ENGLAND. WASHINGTON UNIV,MCDONNELL CTR SPACE SCI,DEPT EARTH & PLANETARY SCI,ST LOUIS,MO 63130. NASA,DIV SOLAR SYST EXPLORAT,WASHINGTON,DC 20546. CORNELL UNIV,DEPT ASTRON,ITHACA,NY 14853. US GEOL SURVEY,FLAGSTAFF,AZ 86001. RP PHILLIPS, RJ (reprint author), SO METHODIST UNIV,DEPT GEOL SCI,DALLAS,TX 75275, USA. NR 50 TC 87 Z9 87 U1 0 U2 8 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 12 PY 1991 VL 252 IS 5003 BP 288 EP 297 DI 10.1126/science.252.5003.288 PG 10 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FG036 UT WOS:A1991FG03600045 PM 17769276 ER PT J AU GARDNER, JV FIELD, ME LEE, H EDWARDS, BE MASSON, DG KENYON, N KIDD, RB AF GARDNER, JV FIELD, ME LEE, H EDWARDS, BE MASSON, DG KENYON, N KIDD, RB TI GROUND-TRUTHING 6.5-KHZ SIDE SCAN SONOGRAPHS - WHAT ARE WE REALLY IMAGING SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID IBERIAN CONTINENTAL-MARGIN; LONG-RANGE SONAR; MARINE-SEDIMENTS; GLORIA SURVEY; SEISMIC DATA; ATTENUATION; TRANSFORM; ATLANTIC; VELOCITY; FAULTS AB A 1000-km2 area on the distal lobe of Monterey Fan shows a digitate pattern of juxtaposed high and low backscatter on GLORIA side scan sonographs. This area was investigated using stereo photography, high-resolution seismic profiles, and measurements of physical properties of cores to quantitatively evaluate the causes of backscatter from the 6.5-kHz side scan sonar. Stereo photography and bottom video were used to determine that the sediment-water interface typically has a bed roughness less than 10 cm over the entire ground truth area; consequently, bed roughness is not a significant contributor to the sonar backscatter. Vertical-incidence 3.5-kHz profiles reveal that high-backscatter areas allow less penetration and have slightly more relief than low-backscatter areas. Closely spaced measurements of p wave velocity, density, and grain size made on transponder-navigated cores are used to investigate the geoacoustic properties of the sediment with the aid of a numerical model. The model results demonstrate that the sediment-water interface is, in most cases, acoustically transparent to the sonar energy and that most or all of the energy is refracted into the sediment to depths of at least a few meters rather than scattered from the surface. The variability of the dominant lithofacies (sands with minor silty clays or silty clay with minor sands) accounts for a regional correlation with backscatter when viewed over hundreds to thousands of square kilometers, but at the detailed scale of hundreds to a few square meters, we have not yet been able to identify a correlation of backscatter intensity with the angle of incidence, surface lithology, measured acoustic impedance, or attenuation. However, there is a qualitative, but unexpected, correlation with lithostratigraphic variability. In this area, thick (up to 50 cm) sand deposits with thin interbeds of silty clay correlate with lower backscatter than do silty clay deposits with thin interbeds of sand. This suggests that volume inhomogeneities and complex constructive and destructive interferences caused by the subsurface volume inhomogeneities within the top few meters of the sediment ultimately modulate the intensity of backscatter. The ground-truthing effort was further complicated by trying to compare the very large sonar footprint of a pixel (approximately 70,000 m2) relative to the area of an individual core (0.006 m2), bottom photograph (approximately 5 m2), or seismic profile. Although 6.5-kHz sonographs appear easy to interpret in a conventional and simplistic manner, caution should be used when interpreting lithofacies from backscatter intensities. C1 UNIV COLL CARDIFF,DEPT GEOL,CARDIFF,WALES. INST OCEANOG SCI,WORMLEY,SURREY,ENGLAND. RP GARDNER, JV (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS999,MENLO PK,CA 94025, USA. NR 55 TC 51 Z9 51 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 5955 EP 5974 DI 10.1029/90JB02730 PG 20 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300005 ER PT J AU SCHLINGER, CM VEBLEN, DR ROSENBAUM, JG AF SCHLINGER, CM VEBLEN, DR ROSENBAUM, JG TI MAGNETISM AND MAGNETIC MINERALOGY OF ASH FLOW TUFFS FROM YUCCA MOUNTAIN, NEVADA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID DOMAIN TITANOMAGNETITE PARTICLES; SOUTHERN NEVADA; SINGLE-DOMAIN; GLASS; ORIGIN AB The magnetic susceptibility (X) and remanent magnetization of an ash flow sheet are profoundly influenced by cooling history after emplacement. Spatial variations in these properties, therefore, provide a potentially useful tool for geological studies. Maxima and minima in X measured along profiles at Yucca Mountain, Nevada, identify persistent magnetic marker horizons within vitric portions of the Tiva Canyon and underlying Topopah Spring Members of the Paintbrush Tuff. The correlatable variations of X with vertical position in these units exist over the 8 km of strike examined. The observed stratigraphic changes in magnetic properties reflect variations in amounts and mineralogy of Fe-Ti oxide phenocrysts, and the presence, shape, size, and mineralogy of magnetic Fe-oxide microcrystals that precipitated at high temperature after emplacement of each sheet. Vitrophyre near the top of the Topopah Spring Member has a distinctive maximum in X, due to titanomagnetite phenocrysts. Susceptibility in the lower portion of the overlying Tiva Canyon Member reaches maximum values of about 1.3x10(-2) (SI) near the base of the member, beneath the columnarly jointed vitrophyre, due to the presence of abundant superparamagnetic cubic Fe-oxide. These elongate microcrystals are several tens of nm long, and are typically deformed and tapered. Up section in the Tiva Canyon Member, the susceptibility decreases, going to a minimum within the columnar vitrophyre. At this stratigraphic level the precipitated Fe-oxides are larger and carry intense NRM of up to 30 A/m; X is only 3x10(-3). The whisker-like microcrystals of Fe-oxide, which typically nucleated on what appears to be chain silicate, grew as needles up to 25-mu-m in length. The size variations of the precipitated Fe-oxides, which were established using transmission electron microscopy (TEM) and petrographic observation, are consistent both with variations in magnetic susceptibility measured at the outcrop and with variations in the intensity of remanent magenetization. Several interpretations of the shape anisotropy of the precipitated Fe-oxide are possible, including growth by a dislocation mechanism. Additionally, the observed elongation of precipitated microcrystals is consistent with theoretical predictions for growth in a uniaxial stress field. Susceptibility variations as established at the outcrop, as well as in the borehole, offer a potentially useful tool for stratigraphic correlation of ash flow sheets. C1 JOHNS HOPKINS UNIV,DEPT EARTH & PLANETARY SCI,BALTIMORE,MD 21218. UNIV UTAH,DEPT GEOL & GEOPHYS,SALT LAKE CITY,UT 84112. US GEOL SURVEY,DENVER FED CTR,DENVER,CO 80225. NR 45 TC 32 Z9 32 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6035 EP 6052 DI 10.1029/90JB02653 PG 18 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300010 ER PT J AU GOLDSTEIN, P ARCHULETA, RJ AF GOLDSTEIN, P ARCHULETA, RJ TI DETERMINISTIC FREQUENCY-WAVE-NUMBER METHODS AND DIRECT MEASUREMENTS OF RUPTURE PROPAGATION DURING EARTHQUAKES USING A DENSE ARRAY - THEORY AND METHODS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID STRESS DROP; RADIATION; MODELS; SIGNALS AB We present an approach for measuring the spatial extent, duration, directions and speeds of rupture propagation during an earthquake using array signal processing techniques. Unlike most previous approaches, no assumptions are made regarding the directions and speeds of propagation. The solution we obtain is unique, and its accuracy, precision and resolution can be estimated. We use preprocessing and coprocessing techniques that improve the accuracy/precision of existing frequency-wavenumber methods. Subarray spatial averaging modifies frequency-wavenumber techniques so that they are sensitive to multiple deterministic (transient) as well as stochastic (stationary) signals. This technique is also advantageous because it ensemble averages the cross spectral matrix and reduces the variance of the frequency-wavenumber spectrum. Seismogram alignment is a preprocessing procedure that accounts for nonplanar wavefronts due to lateral velocity variations beneath an array. This procedure also allows us to study signals of interest using much shorter time windows than has previously been possible. The use of short time windows is important for reducing uncertainty in estimates of arrival times of seismic phases. We tested subarray spatial averaging and seismogram alignment with a variety of frequency-wavenumber techniques and found that the multiple signal classification (MUSIC) method gave the best resolution of multiple signals. We also note that standard theoretical estimates of uncertainties in peak locations of frequency-wavenumber spectra are much smaller than those typically observed using seismic arrays and we present a different formula that more accurately describes observed uncertainties. Using synthetic P and S body-wave seismograms from extended earthquake sources we show that the above array signal processing techniques can be combined with ray theory to obtain accurate estimates of the locations and rupture times of an earthquake's high-frequency seismic sources. We show how to estimate uncertainties in source locations and rupture times due to limitations of the data, uncertainties in source parameters, and uncertainties in velocity structure. We find that the size of the uncertainties can be very sensitive to a fault's geometry relative to an array and we suggest criteria for optimizing an array's location. We show that high-frequency source locations and their associated rupture times can be used to estimate an earthquake's spatial extent, duration, directions and speeds of rupture propagation. C1 US GEOL SURVEY,MENLO PK,CA 94025. UNIV CALIF SANTA BARBARA,DEPT GEOL SCI,SANTA BARBARA,CA 93106. NR 25 TC 48 Z9 52 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6173 EP 6185 DI 10.1029/90JB02123 PG 13 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300020 ER PT J AU FERRAZZINI, V AKI, K CHOUET, B AF FERRAZZINI, V AKI, K CHOUET, B TI CHARACTERISTICS OF SEISMIC-WAVES COMPOSING HAWAIIAN VOLCANIC TREMOR AND GAS-PISTON EVENTS OBSERVED BY A NEAR-SOURCE ARRAY SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID KILAUEA AB A correlation method, specifically designed for describing the characteristics of a complex wave field, is applied to volcanic tremor and gas-piston events recorded by a semicircular array of GEOS instruments set at the foot of the Puu Oo crater on the east rift of Kilauea volcano, Hawaii. The spatial patterns of correlation coefficients obtained as functions of frequency for the three components of motion over the entire array are similar for gas-piston events and tremor, and clearly depict dispersive waves propagating across the array from the direction of Puu Oo. The wave fields are composed of comparable amounts of Rayleigh and Love waves propagating with similar and extremely slow phase velocities ranging from 700 m/s at 2 Hz to 300 m/s at 8 Hz. The highly cracked solidified lava flow on which the array was deployed, and subjacent structure of alternating lava and ash layers formed during repeated eruptions of Puu Oo since 1983, appear to be responsible for the low velocities observed. The results from Puu Oo stand in sharp contrast to those obtained in an experiment conducted in 1976 on the partially solidified lava lake of Kilauea Iki. Rayleigh waves were not observed in Kilauea Iki, but well-developed trains of Love waves were seen to propagate there with velocities twice as high as those observed near Puu Oo. These differences in the propagation characteristics of surface waves at the two sites may be attributed to the presence of a soft horizontal layer of molten rock in Kilauea Iki, which may have lowered the phase velocity of Rayleigh waves more drastically than that of Love waves, resulting in severe scattering of the Rayleigh wave mode. On the other hand, the thin superficial pahoehoe flow under our array at Puu Oo may have favored the development of vertical columnar joints more extensively at this location than at Kilauea Iki, which may have reduced the shear moduli controlling the Love wave mode. The average phase velocities in the frequency band from 2 to 5 Hz found at Puu Oo are roughly similar to those determined for tremor at Klyuchevskoy volcano, Kamchatka, but the frequency dependence appears much stronger at Puu Oo. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP FERRAZZINI, V (reprint author), UNIV SO CALIF,DEPT GEOL SCI,LOS ANGELES,CA 90089, USA. RI Ferrazzini, Valerie/E-8032-2017 OI Ferrazzini, Valerie/0000-0001-7908-1429 NR 24 TC 93 Z9 93 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6199 EP 6209 DI 10.1029/90JB02781 PG 11 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300022 ER PT J AU CATCHINGS, RD MOONEY, WD AF CATCHINGS, RD MOONEY, WD TI BASIN AND RANGE CRUSTAL AND UPPER MANTLE STRUCTURE, NORTHWEST TO CENTRAL NEVADA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID WESTERN UNITED-STATES; GREAT-BASIN; PROVINCE; STRESS AB We present a interpretation of the crustal and uppermost mantle structure of the Basin and Range of northwestern Nevada based on seismic refraction/wide-angle reflection, near-vertical reflection, and gravity data. In comparison to most previous estimates, we find that the crust is somewhat thicker (32-36 km versus 22-30 km), and the uppermost mantle velocity is somewhat higher (8.0 km/s versus 7.3-7.9 km/s). Along our transects, the crust is thinnest (32 km) in the Carson Sink-Buena Vista Valley region and increases by 2-4 km to the west and east, respectively. There is considerable complexity throughout the crust where velocities range from of 2.5 km/s at the surface to 7.4 km/s in the lowermost crust. Variations in velocity and structure of the upper crustal layers reveal apparent basement velocity depressions (areas of lower velocities extending up to 10 km in depth) that underlie some surface ranges as well as the basins. The middle crust rises from about 20 km beneath central Nevada to within 12 km of the surface beneath the area of thinnest crust and is characterized by a modest (approximately 0.1 km/s) change in velocity and low-velocity gradients. These midcrustal layers mark the onset of high crustal reflectivity and the apparent limiting depth to which Basin and Range faults can be traced in near-vertical reflection profiles, suggesting that these midcrustal layers represent the transition between the brittle and ductile zones of the crust. The lower crust is more structurally complex, with layers thickening and thinning in a systematic manner with the upper crustal layers; generally, where there are velocity depressions in the upper crust, the lower crust is thickest and shallowest. The geometry of these lower crustal layers (derived from refraction modeling) coincides with changes in the crustal reflectivity, determined from the Consortium of Continental Reflection Profiling reflection data. The lower crustal layer is unusually high in velocity (7.4 km/s) and is likely the layer identified as mantle in some previous studies. We do not identify the 7.4 km/s layer as mantle because (1) there is an underlying layer with a velocity (8.0 km/s) that is more consistent with the worldwide average velocity for the upper mantle, and (2) the 7.4 km/s layer does not correspond to the "reflection" Moho. Gravity modeling and comparison to existing seismic models show a general consensus in many aspects with respect to crustal structure. This new model forms the basis for speculation on some of the processes associated with rifting of the Basin and Range Province. One such process, lithospheric magmatism, is inferred from the strong attenuation of transmitted seismic waves, which occurs at the same interface at which high-amplitude, bright spot reflections originate. Unlike previous models, the overall structure and velocity of the crust and uppermost mantle of our new model are similar to other regions worldwide which have undergone high degrees of extension. RP US GEOL SURVEY, MS 977, 345 MIDDLEFIELD RD, MENLO PK, CA 94025 USA. NR 42 TC 49 Z9 49 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6247 EP 6267 DI 10.1029/91JB00194 PG 21 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300026 ER PT J AU FRANKEL, A AF FRANKEL, A TI MECHANISMS OF SEISMIC ATTENUATION IN THE CRUST - SCATTERING AND ANELASTICITY IN NEW-YORK-STATE, SOUTH-AFRICA, AND SOUTHERN CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID INTRINSIC ATTENUATION; WAVE SCATTERING; CODA WAVES; LITHOSPHERE; EARTHQUAKE; ARRAY; ANZA; SEPARATION; MODEL AB The envelopes of high-frequency seismograms from earthquakes in New York State, South Africa, and southern California are analyzed to determine how much of the observed attenuation of shear waves in the crust is caused by anelasticity and how much is produced by scattering from small-scale heterogeneities. For seismograms from New York and South Africa, there is a systematic enrichment of high-frequency energy that develops in the coda relative to the direct S or L(g) waves. This enrichment of high frequencies in the coda grows larger with increasing source-receiver distance. This implies that high-frequency energy is scattered from the direct wave into the coda as the shear wave propagates in the crust. I use the growth with source-receiver distance of the high-frequency energy in the coda relative to the direct wave to estimate the scattering attenuation of the crust. For seismograms from New York, it is consistently observed that the time decay of high-frequency energy in the coda, when compared to the low-frequency coda decay, is less than the relative decay of high-frequency energy with travel time in the L(g) wave. This observations supports the idea that the time decay of the coda is controlled mainly by the anelastic attenuation and is insensitive to the scattering attenuation, as suggested by coda models incorporating conservation of energy such as the energy flux model. I use the relative time decay of high-frequency energy in the coda to determine the anelastic attenuation. This analysis indicates that the observed attenuation of 15-Hz L(g) waves in New York State (DELTA = 100-400 km) is caused about equally by scattering and anelasticity. Using the estimate of L(g) wave Q as a constraint, I find that the scattering Q in the crust of New York is either independent of frequency or increases with frequency closed-integral slower than closed-integral-0.3. This implies that the one-dimensional power spectrum of spatial velocity variations in the crust of New York decays with increasing wavenumber k more slowly than k-1.3, for length scales of about 0.2 to 1 km. A similar analysis for South Africa indicates that scattering is the major cause of the observed S wave attenuation of high-frequency energy (30 Hz) at local distances ( < 100 km). For southern California, the extent of the scattering attenuation is unclear from the data, although the relatively steep coda decay of southern California implies that anelastic attenuation is stronger there than in New York or South Africa. At 3 Hz, the coda decays for lapse times of 10-45 s are similar to the decays of S wave amplitudes with travel time for the three regions. However, the 30-Hz coda decays are substantially less than the 30-Hz S wave decays with travel time, producing coda Q values that are much higher than the S wave Q in each area. For southern California and New York State, the 3-Hz coda Q taken from the late coda (50-110 s) is comparable to the L(g) wave Q. However, the 3-Hz coda Q for South Africa over these lapse times is about 5 times the estimated L(g) wave Q. For all three areas, the frequency dependence of the coda Q does not match the frequency dependence of the S wave Q, and for New York and South Africa, it changes with lapse time. RP FRANKEL, A (reprint author), US GEOL SURVEY,922 NATL CTR,RESTON,VA 22092, USA. NR 27 TC 58 Z9 58 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6269 EP 6289 DI 10.1029/91JB00192 PG 21 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300027 ER PT J AU FRANKEL, A AF FRANKEL, A TI HIGH-FREQUENCY SPECTRAL FALLOFF OF EARTHQUAKES, FRACTAL DIMENSION OF COMPLEX RUPTURE, B-VALUE, AND THE SCALING OF STRENGTH ON FAULTS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID STRONG GROUND MOTION; SAN-ANDREAS FAULT; TECTONIC STRESS; SOURCE MODELS; CALIFORNIA; RADIATION; WAVES AB The high-frequency falloff omega-gamma of earthquake displacement spectra and the b value of aftershock sequences are attributed to the character of spatially varying strength along fault zones. I assume that the high frequency energy of a main shock is produced by a self-similar distribution of subevents, where the number of subevents with radii greater than R is proportional to R(-D), D being the fractal dimension. In this model, an earthquake is composed of a hierarchical set of smaller earthquakes. The static stress drop is parameterized to be proportional to R-eta, and strength is assumed to be proportional to static stress drop. I find that a distribution of subevents with D = 2 and stress drop independent of seismic moment (eta = 0) produces a main shock with an omega-2 falloff, if the subevent areas fill the rupture area of the main shock. By equating subevents to "islands" of high stress of a random, self-similar stress field on a fault, I relate D to the scaling of strength on a fault, such that D = 2 - eta. Thus D = 2 corresponds to constant stress drop scaling (eta = 0) and scale-invariant fault strength. A self-similar model of aftershock rupture zones on a fault is used to determine the relationship between the b value, the size distribution of aftershock rupture zones, and the scaling of strength on a fault. The b value for aftershock sequences on a fault is found to equal (3 - 1.5-eta)/(3 + eta). Therefore this model indicates that the typically observed spectral falloffs of omega-2 and b values of 1 can be entirely caused by scale-invariant strength (eta = 0) along fault zones. RP FRANKEL, A (reprint author), US GEOL SURVEY,922 NATL CTR,RESTON,VA 22092, USA. NR 39 TC 99 Z9 107 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6291 EP 6302 DI 10.1029/91JB00237 PG 12 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300028 ER PT J AU MICHAEL, AJ AF MICHAEL, AJ TI SPATIAL VARIATIONS IN STRESS WITHIN THE 1987 WHITTIER NARROWS, CALIFORNIA, AFTERSHOCK SEQUENCE - NEW TECHNIQUES AND RESULTS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID EARTHQUAKE SEQUENCE; SOUTHERN-CALIFORNIA; TECTONIC ANALYSIS; FOCAL MECHANISMS; REGIONAL STRESS; SLIP DATA; FAULT; TENSOR AB The M(L) = 5.9 Whittier Narrows, California, earthquake of October 1, 1987, triggered a complex aftershock sequence. The aftershocks had many different focal mechanisms including thrusting on E-W striking, north dipping planes (similar to the main shock), right-lateral motion on NW-SE striking planes (similar to the M(L) = 5.3 aftershock on October 4, 1987), thrusting on N-S striking planes, and left-lateral motion on N-S striking planes. I attempt to interpret these mechanisms in terms of a stress field that may have caused them. Previously, stress inversion methods based on focal mechanisms assumed that the stress field was spatially uniform. In order to test for the spatially varying effect of the main shock's dislocation on the aftershocks' focal mechanisms a new inversion technique was developed that solves for a uniform stress field that is superimposed on a given spatially varying stress field. A series of simulations were performed to test both the new method and an older method that uses only the uniform component of the stress field. These simulations show that both techniques work but will be limited by the amount of noise in the data and the accuracy to which the given spatially varying stress field resembles the actual spatially varying stresses. Most importantly, the simulations show that the older methods do work when the stress field has a uniform component that is at least as large as the spatially varying component. The simulations also show that when applying the older stress inversion techniques, one can determine if the results are valid, and the amount of spatially varying stresses present, by examining the misfit between the data and the model. Application of these techniques to the Whitter Narrows aftershocks suggests that the uniform component of the stress field, and the complex faulting, corresponds to the response of an elastic halfspace to a simple regional N-S compression. The misfit between the data and the uniform model demonstrate the presence of spatially varying stresses at Whittier Narrows; however, their form, as shown by the simulations, can not be determined with this data set and these techniques. RP MICHAEL, AJ (reprint author), US GEOL SURVEY,MS 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. RI Michael, Andrew/A-5059-2010 OI Michael, Andrew/0000-0002-2403-5019 NR 21 TC 65 Z9 70 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6303 EP 6319 DI 10.1029/91JB00195 PG 17 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300029 ER PT J AU CRAMPIN, S BOOTH, DC EVANS, R PEACOCK, S FLETCHER, JB AF CRAMPIN, S BOOTH, DC EVANS, R PEACOCK, S FLETCHER, JB TI COMMENT ON QUANTITATIVE MEASUREMENTS OF SHEAR-WAVE POLARIZATIONS AT THE ANZA SEISMIC NETWORK, SOUTHERN CALIFORNIA - IMPLICATIONS FOR SHEAR-WAVE SPLITTING AND EARTHQUAKE PREDICTION BY ASTER,RICHARD,C., SHEARER,PETER,M., AND BERGER,JOHN SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID ANISOTROPY C1 US GEOL SURVEY,MENLO PK,CA 94025. UNIV READING,POSTGRAD RES INST SEDIMENTOL,READING RG6 2AB,BERKS,ENGLAND. RP CRAMPIN, S (reprint author), BRITISH GEOL SURVEY,MURCHISON HOUSE,W MAINS RD,EDINBURGH EH9 3LA,SCOTLAND. NR 24 TC 61 Z9 61 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6403 EP 6414 DI 10.1029/90JB02453 PG 12 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300034 ER PT J AU MOONEY, WD AF MOONEY, WD TI INTRODUCTION TO SPECIAL SECTION ON EDGE AND RELATED SEISMIC PROJECTS, ONSHORE-OFFSHORE CALIFORNIA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article RP MOONEY, WD (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6421 EP 6421 DI 10.1029/91JB00843 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300036 ER PT J AU CORDELL, L ZORIN, YA KELLER, GR AF CORDELL, L ZORIN, YA KELLER, GR TI THE DECOMPENSATIVE GRAVITY-ANOMALY AND DEEP-STRUCTURE OF THE REGION OF THE RIO-GRANDE RIFT SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID BAIKAL RIFT; LITHOSPHERE; MISSOURI; BENEATH AB An isostatic correction is commonly made to Bouguer anomaly gravity data to remove the gravity effect of isostatic compensation of topographic loads. In the USSR a "decompensative" correction has then been made to the isostatic gravity anomaly to remove the gravity effect of isostatic compensation of geologic loads as well. Under an hypothesis of local (as opposed to regional) compensation the gravity effect of a shallow geological body can be separated from that of its inferred deep compensating root by deconvolution. By contrast with the procedure originally defined by Zorin, we employ here calculations in the wave number domain, leading to an efficient and exact solution. The decompensative transfer function acts to increase amplitude of the isostatic anomaly at all wavelengths, but especially at the low end of the isostatic anomaly spectrum in the 200-600 km wavelength region, where anomaly amplitudes may increase by as much as a factor of 2. In a 1200 x 1200 km region centered on the Rio Grande rift the decompensative correction ranges from about -35 to +25 mGal. The rift is not particularly apparent in the decompensative correction nor is the rift any more apparent in the decompensative anomaly than in the isostatic anomaly. The decompensative anomaly, however, highlights an arcuate gravity low and a system of gravity highs inferred to reflect prerift welts of mass concentration which have indirectly influenced the position of the rift and its segmentation and zones of accommodation. Under the assumptions made, if the decompensative anomaly is subtracted from the Bouguer anomaly, then the residual is the gravity anomaly field of deep structure, without gravity effects of shallow sources in the upper crust. We suppose this gravity field to be dominated by the gravity effects of the density contrast across the crust-mantle boundary (Moho) and the density contrast at the lithosphere-asthenosphere boundary. Using available seismic data to (weakly) constrain the Moho surface, we invert the residual gravity field for topography of the base of the lithosphere. Lithosphere is found to be 200 km thick in the High Plains; 40-50 km in the eastern Great Basin; 75-100 km in the Colorado Plateau, and as thin as 40 km in the southern Rio Grande rift. In the area studied, the thickness of the lithosphere is everywhere greater than that of the crust. An asthenosphere bulge closely tracks the axis of the rift and is symmetrical to it, by contrast with asymmetry that might be inferred from broad features of the Bouguer anomaly. The separation of gravity effects made possible by the decompensative correction shows how the rift is fundamentally controlled by thinning of the lithosphere, yet in detail is deflected by long-lived tectonic welts in the shallow, brittle crust. C1 UNIV TEXAS,DEPT GEOL SCI,EL PASO,TX 79968. ACAD SCI USSR,INST EARTHS CRUST,IRKUTSK 664033,USSR. RP CORDELL, L (reprint author), US GEOL SURVEY,DENVER FED CTR,POB 25046,DENVER,CO 80225, USA. NR 31 TC 36 Z9 38 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD APR 10 PY 1991 VL 96 IS B4 BP 6557 EP 6568 DI 10.1029/91JB00008 PG 12 WC Geosciences, Multidisciplinary SC Geology GA FG773 UT WOS:A1991FG77300045 ER PT J AU SAVAGE, JC LISOWSKI, M AF SAVAGE, JC LISOWSKI, M TI STRAIN-MEASUREMENTS AND THE POTENTIAL FOR A GREAT SUBDUCTION EARTHQUAKE OFF THE COAST OF WASHINGTON SO SCIENCE LA English DT Article ID ZONE AB Geodetic measurements of deformation in northwestern Washington indicate that strain is accumulating at a rate close to that predicted by a model of the Cascadia subduction zone in which the plate interface underlying the continental slope and outer continental shelf is currently locked but the remainder of the interface slips continuously. Presumably this locked segment will eventually rupture in a great thrust earthquake with a down-dip extent greater than 100 kilometers. RP SAVAGE, JC (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MAIL STOP 977,MENLO PK,CA 94025, USA. NR 21 TC 22 Z9 22 U1 0 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 5 PY 1991 VL 252 IS 5002 BP 101 EP 103 DI 10.1126/science.252.5002.101 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FE952 UT WOS:A1991FE95200041 PM 17739080 ER PT J AU LOVLEY, DR PHILLIPS, EJP GORBY, YA LANDA, ER AF LOVLEY, DR PHILLIPS, EJP GORBY, YA LANDA, ER TI MICROBIAL REDUCTION OF URANIUM SO NATURE LA English DT Article ID IRON REDUCTION; SEDIMENTS; DEPOSITION; OXIDATION; MECHANISMS; MANGANESE; THORIUM; SEA AB REDUCTION of the soluble, oxidized form of uranium, U(VI), to insoluble U(IV) is an important mechanism for the immobilization of uranium in aquatic sediments and for the formation of some uranium ores 1-10. U(VI) reduction has generally been regarded as an abiological reaction in which sulphide, molecular hydrogen or organic compounds function as the reductant 1,2,5,11. Microbial involvement in U(VI) reduction has been considered to be limited to indirect effects, such as microbial metabolism providing the reduced compounds for abiological U(VI) reduction and microbial cell walls providing a surface to stimulate abiological U(VI) reduction 1,12,13. We report here, however, that dissimilatory Fe(III)-reducing microorganisms can obtain energy for growth by electron transport to U(VI). This novel form of microbial metabolism can be much faster than commonly cited abiological mechanisms for U(VI) reduction. Not only do these findings expand the known potential terminal electron acceptors for microbial energy transduction, they offer a likely explanation for the deposition of uranium in aquatic sediments and aquifers, and suggest a method for biological remediation of environments contaminated with uranium. RP LOVLEY, DR (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,430 NATL CTR,RESTON,VA 22092, USA. NR 30 TC 738 Z9 770 U1 18 U2 144 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD APR 4 PY 1991 VL 350 IS 6317 BP 413 EP 416 DI 10.1038/350413a0 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FF042 UT WOS:A1991FF04200046 ER PT J AU BISCHOFF, JL AF BISCHOFF, JL TI DENSITIES OF LIQUIDS AND VAPORS IN BOILING NACL-H2O SOLUTIONS - A PVTX SUMMARY FROM 300-DEGREES-C TO 500-DEGREES-C SO AMERICAN JOURNAL OF SCIENCE LA English DT Article ID SYSTEM NACL-H2O; CRITICAL-TEMPERATURE; PHASE-RELATIONS; CRITICAL REGION; EQUATION; STATE; H2O; SEAWATER; HALITE AB Experimental data for densities of liquids and vapors on the two-phase surface of the system NaCL-H2O were complied and evaluated to provide a complete summary between 300-degrees and 500-degrees-C, a range for which the system changes from subcritical to critical behavior. Data for the NaCl-H2O critical line and for the three-phase assemblage halite + liquid + vapor were first evaluated over a much wider T-P range, and the best fits of these curves were used as extrema to guide curve positioning for P-V isothermal plots of experimental points in between. Data were replotted as T-V isobars, corrected for consistency, and replotted again as V-x isotherms and finally as P-T isochores in an iterative process until an internally consistent set of densities was obtained. The results are added to a previously published PTx summary compiled in the same manner to provide a PTx summary of the present state of knowledge. Results are in table form of use to the understanding of two-phase behavior in boiling hydrothermal systems and to theoretical modeling of this important system. RP BISCHOFF, JL (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 33 TC 141 Z9 183 U1 0 U2 14 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0002-9599 J9 AM J SCI JI Am. J. Sci. PD APR PY 1991 VL 291 IS 4 BP 309 EP 338 PG 30 WC Geosciences, Multidisciplinary SC Geology GA FF648 UT WOS:A1991FF64800001 ER PT J AU ZEN, EA AF ZEN, EA TI PHANEROZOIC DENUDATION HISTORY OF THE SOUTHERN NEW-ENGLAND APPALACHIANS DEDUCED FROM PRESSURE DATA SO AMERICAN JOURNAL OF SCIENCE LA English DT Article ID ACADIAN THERMAL HISTORY; SEISMIC-REFLECTION; NEW-HAMPSHIRE; NORTHERN APPALACHIANS; UNITED-STATES; WESTERN MAINE; VERMONT; QUEBEC; EASTERN; METAMORPHISM AB Data on depth of burial (or its equivalent, pressure, P) are collected from the literature for the part of the Appalachians that extends from western Maine to southeastern New York. These data are based on regional metamorphic assemblages, contact aureole assemblages, and igneous rocks, supplemented by regional geological considerations. For the Taconian orogeny, the data show an apparently narrow high-P ridge at the western limit of the Brompton-Cameron terrane; for the Acadian orogeny, they show a broad high-P plateau in this terrane and in the Central Maine terrane, and a modestly high P record in the Nashoba-Casco-Miramichi composite terrane. Alleghanian pressure data are scanty but show no high-P region except near coastal Rhode Island. Denudation rates for these terranes average about 0.1 km/my for the Taconian-Acadian and Acadian-Late Triassic intervals and for the Paleozoic as a whole. Exposed rocks in both the North American craton and Atlantica composite terrane show low P throughout the Paleozoic and little evidence of denudation; thus, they demonstrate differential uplift between terranes during the Paleozoic. The Taconian high-P ridge shows much P reduction in the Acadian, but there is no sedimentary record of rapid erosion in the Hudson Valley-Lake Champlain-St. Lawrence Valley belt to the west, where a thin sequece of fine-grained, calcareous rocks indicates deposition between these orogenies in a shallow marine environment. Coarse orogenic sediments of this time period were shed eastward to form a "northwest Maine" sequence that includes the Rangeley Formation and that was terminated abruptly at the peak of the Acadian orogeny when the Catskill Delta deposition began. These records are interpreted to mean that the Acadian orogeny smashed the northwest Maine basin and shoved much of the supracrustal material westward to bring the Taconian high-P belt to its present location, concomitantly both reducing the pressure and causing molasse sedimentation to the west. In contrast, the post-Triassic denudation record, encoded in the shallow (< 1-2 kb) Jurassic-Cretaceous White Mountain Plutonic-Volcanic Suite, indicates denudation at about 0.01 km/my; this rate applies to all the terranes where the rocks appear. The modern Moho in Maine rises steadily from about 43 km near the Quebec border to about 35 km near the coast and truncates terrane-bounding faults; presumably this Moho reflects crustal reconstitution during opening of the Atlantic, a process that welded the Paleozoic accreted terranes into a mechanically coherent unit. C1 US GEOL SURVEY,RESTON,VA 22092. NR 95 TC 12 Z9 12 U1 1 U2 2 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0002-9599 J9 AM J SCI JI Am. J. Sci. PD APR PY 1991 VL 291 IS 4 BP 401 EP 424 PG 24 WC Geosciences, Multidisciplinary SC Geology GA FF648 UT WOS:A1991FF64800004 ER PT J AU JAMES, PW MAUGHAN, OE ZALE, AV AF JAMES, PW MAUGHAN, OE ZALE, AV TI LIFE-HISTORY OF THE LEOPARD DARTER PERCINA - PANTHERINA IN GLOVER RIVER, OKLAHOMA SO AMERICAN MIDLAND NATURALIST LA English DT Article ID HABITAT AB Life history data were collected by capturing specimens, observing darters in captivity and examining preserved specimens. Field observations and measurements were made monthly at six sites in Glover River, Oklahoma, from August 1985 to September 1988. Percina pantherina remained exclusively in pools during summer, autumn and winter. The fish were usually found at water depths of 25-75 cm, over substrates of cobble and boulder where no current was detectable. The fish spawned on riffles from mid-March to mid-May at water temperatures of 12-20 C. Eggs were buried in patches of fine gravel at water depths of 30-90 cm, where current velocities were 0-50 cm/sec. Growth of juveniles was rapid; the young reached adult size by mid-August. Juveniles were found with adults in the same habitats in pools. Longevity was about 18 months. Abundance was relatively low at all sites and decreased progressively throughout summer. The life history was characterized by rapid growth to maturity; a short life span; and high mortality, both of post-spawning adults and young-of-the-year. C1 OKLAHOMA STATE UNIV,DEPT ZOOL,US FISH & WILDLIFE SERV,OKLAHOMA COOPERAT FISH & WILDLIFE RES UNIT,STILLWATER,OK 74078. NR 16 TC 9 Z9 10 U1 1 U2 3 PU AMER MIDLAND NATURALIST PI NOTRE DAME PA UNIV NOTRE DAME, NOTRE DAME, IN 46556 SN 0003-0031 J9 AM MIDL NAT JI Am. Midl. Nat. PD APR PY 1991 VL 125 IS 2 BP 173 EP 179 DI 10.2307/2426220 PG 7 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA FP088 UT WOS:A1991FP08800001 ER PT J AU LI, PJ MARTIN, TE AF LI, PJ MARTIN, TE TI NEST-SITE SELECTION AND NESTING SUCCESS OF CAVITY-NESTING BIRDS IN HIGH ELEVATION FOREST DRAINAGES SO AUK LA English DT Article ID DOUGLAS-FIR FORESTS; PONDEROSA PINE; BREEDING BIRDS; WESTERN OREGON; TENGMALMS OWL; HOUSE WRENS; PREDATION; ARIZONA; HABITAT; LIMIT AB We identified habitat features that characterized successful and unsuccessful nest sites, nest sites vs. random sites, and differences among coexisting species of cavity-nesting birds for 356 nests in central Arizona. Live and, more commonly, dead quaking aspens (Populus tremuloides) were used for 88% of all nest sites, but aspens constituted only 12% of all trees in random plots (n = 152). Nest patches (11.3-m-radius circle centered on the nest tree) of most bird species contained significantly more aspens and conifers, which provided foraging substrates for cavity-nesting species, than random plots, but the patches had fewer deciduous trees (except aspens). Thus, more potential nest sites and foraging substrates existed in chosen nest patches than in random plots. Failed nests generally were more concealed by foliage and were closer to conifers. Nest success was lower for species with lower nest height. Reduced nest success at lower and more concealed nests may occur because predators are more successful. Nonexcavator species had lower nesting success than excavator species possibly because they nested lower, had greater nest concealment, used older cavities, and tended to have smaller body mass. C1 ARIZONA STATE UNIV,DEPT ZOOL,TEMPE,AZ 85287. RP LI, PJ (reprint author), UNIV ARKANSAS,DEPT ZOOL,ARKANSAS COOPERAT FISH & WILDLIFE RES UNIT,US FISH & WILDLIFE SERV,FAYETTEVILLE,AR 72701, USA. RI Martin, Thomas/F-6016-2011 OI Martin, Thomas/0000-0002-4028-4867 NR 43 TC 186 Z9 196 U1 2 U2 26 PU AMER ORNITHOLOGISTS UNION PI LAWRENCE PA ORNITHOLOGICAL SOC NORTH AMER PO BOX 1897, LAWRENCE, KS 66044-8897 SN 0004-8038 J9 AUK JI AUK PD APR PY 1991 VL 108 IS 2 BP 405 EP 418 PG 14 WC Ornithology SC Zoology GA FK703 UT WOS:A1991FK70300020 ER PT J AU TINER, RW AF TINER, RW TI THE CONCEPT OF A HYDROPHYTE FOR WETLAND IDENTIFICATION - INDIVIDUAL PLANTS ADAPT TO WET ENVIRONMENTS SO BIOSCIENCE LA English DT Article ID FREQUENCY RP TINER, RW (reprint author), US FISH & WILDLIFE SERV,NEWTON CORNER,MA 02158, USA. NR 61 TC 54 Z9 61 U1 0 U2 7 PU AMER INST BIOLOGICAL SCI PI WASHINGTON PA 1444 EYE ST, NW, STE 200, WASHINGTON, DC 20005 SN 0006-3568 J9 BIOSCIENCE JI Bioscience PD APR PY 1991 VL 41 IS 4 BP 236 EP 247 DI 10.2307/1311413 PG 12 WC Biology SC Life Sciences & Biomedicine - Other Topics GA FD177 UT WOS:A1991FD17700007 ER PT J AU HARTZELL, S MENDOZA, C AF HARTZELL, S MENDOZA, C TI APPLICATION OF AN ITERATIVE LEAST-SQUARES WAVE-FORM INVERSION OF STRONG-MOTION AND TELESEISMIC RECORDS TO THE 1978 TABAS, IRAN, EARTHQUAKE SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID RUPTURE HISTORY; MAIN SHOCK; AFTERSHOCK; CALIFORNIA; MECHANISM; GEOMETRY; FAULT AB An iterative least-squares technique is used to simultaneously invert the strong-motion records and teleseismic P waveforms for the 1978 Tabas, Iran, earthquake to deduce the rupture history. The method solves for both slip amplitudes and rupture times on a finite fault. Several inversions of the data are done to determine the best-fitting hypocenter, average rupture velocity, and source-time function, within the range of our parameter search. The effects of using different data sets and different parametrizations of the problem (linear versus nonlinear) are also considered. Teleseismic body waves are shown to be essential to obtain a reliable solution due to the sparse coverage of the fault plane by strong-motion stations. A simple triangular source-time function is compared with a modified Kostrov source-time function for a circular rupture and a constant propagating stress drop. Although the waveforms used in the inversions can not resolve between these two time functions, the Kostrov source-time function gives a moment estimate and maximum fault displacement more consistent with long-period surface waves and field observations. The results of the iterative inversion for slip amplitudes and rupture times are compared with the results of a linear inversion for slip amplitudes in which the rupture velocity is fixed. Flexibility in the sequence of faulting for the linear inversion is obtained by allowing multiple rupture intervals. A consensus of all the inversion runs indicates a complex, multiple source for the Tabas Tabas earthquake, with four main source regions over a fault length of 90 km and an average rupture velocity of 2.5 km/sec. C1 US GEOL SURVEY,NATL EARTHQUAKE INFORMAT CTR,DENVER,CO 80225. RP HARTZELL, S (reprint author), US GEOL SURVEY,GEOL RISK ASSESSMENT BRANCH,BOX 25046,MS 966,DENVER,CO 80225, USA. NR 31 TC 40 Z9 42 U1 0 U2 1 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD APR PY 1991 VL 81 IS 2 BP 305 EP 331 PG 27 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FF669 UT WOS:A1991FF66900001 ER PT J AU LANGER, CJ BOLLINGER, GA AF LANGER, CJ BOLLINGER, GA TI THE SOUTHEASTERN ILLINOIS EARTHQUAKE OF 10 JUNE 1987 - THE LATER AFTERSHOCKS SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID MADRID SEISMIC ZONE; FOCAL MECHANISMS; MID-PLATE; MAGNITUDE; BASIN AB The 10 June 1987 southeastern Illinois earthquake (m(bLg) = 5.2) was the seventh in a series of moderate magnitude (greater-than-or-equal-to 4.5) MMI VII shocks to occur in the Wabash Valley seismic zone of southeastern Illinois and southwestern Indiana since 1891. Located about 200 km east of St. Louis, Missouri, the shock caused minor damage in the epicentral area, had a contiguous felt area of about 433,000 km2, and had a total felt area over 1 million km2. Within 47 hours after the main shock, a cooperative effort between the U.S. Geological Survey and Memphis State University installed a 15-station aftershock monitoring network (later expanded to 21 instruments) that recorded more than 100 aftershocks in the following 4-day period. Results from the 56 aftershocks that were well located indicate a compact, cylindrically shaped aftershock volume about 1.7 km long, 0.8 km wide, and with a vertical distribution between about 9 and 12 km in depth. Composite focal mechanism solutions of the aftershocks suggest that the predominant mode of faulting is reverse slip, but some strike-slip type motion occurred similar to the mechanism for the main shock as determined from teleseismic data. The maximum principal compressive stress (P axes) is oriented easterly to east-southeasterly and is subhorizontal in plunge. These results, combined with historical observations and the recent discovery of earthquake-induced liquefaction features in the area, imply that the seismic potential of the zone may be greater than generally perceived. C1 VIRGINIA POLYTECH INST & STATE UNIV,SEISMOL OBSERV,BLACKSBURG,VA 24061. RP LANGER, CJ (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,MS 966,DENVER,CO 80225, USA. NR 46 TC 18 Z9 18 U1 0 U2 0 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD APR PY 1991 VL 81 IS 2 BP 423 EP 445 PG 23 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FF669 UT WOS:A1991FF66900007 ER PT J AU DEWEY, JW AF DEWEY, JW TI THE 1954 AND 1980 ALGERIAN EARTHQUAKES - IMPLICATIONS FOR THE CHARACTERISTIC-DISPLACEMENT MODEL OF FAULT BEHAVIOR SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID 10 OCTOBER 1980; EL-ASNAM EARTHQUAKE; SAN-ANDREAS FAULT; THRUST-FAULT; NAHANNI EARTHQUAKES; RECURRENCE MODEL; RUPTURE; AFTERSHOCK; TECTONICS; GEOMETRY AB Joint epicenter determination of earthquakes that occurred in northern Algeria near Ech Cheliff (named Orleansville in 1954 and El Asnam in 1980) shows that the earthquake of 9 September 1954 (M = 6.5) occurred at nearly the same location as the earthquake of 10 October 1980 (M = 7.3). The 1954 main shock and earliest aftershocks were concentrated close to the boundaries of segment B (nomenclature of Deschamps et al., 1982; King and Yielding, 1984) of the 1980 fault system, which was to experience approximately 8 m of slip in the 1980 earthquake. Later aftershocks of the 1954 earthquake were spread over a broad area, notably in a region north of the 1980 fault system that also experienced many aftershocks to the 1980 earthquake. The closeness of the 1954 main shock and earliest aftershocks to the 1980 segment B implies that the 1954 earthquake involved either (1) rupture of segment B proper, or (2) rupture of a distinct fault in the hanging wall or footwall block of segment B. The first interpretation cannot be accommodated in the characteristic-displacement model of fault behavior but instead requires a model, such as the time-predictable model, which would permit slip in 1954 to have released only a fraction of the elastic strain that was stored on segment B and which would later be released in 1980. The second interpretation, specifically with rupture in the hanging-wall block of segment B, accounts more directly than the first interpretation for differences in the focal mechanisms and ground deformations associated with the two main shocks; this interpretation is therefore preferred. The second interpretation is consistent with a characteristic-displacement model of the 1980 fault system. No matter how it is modeled, the Algerian episode provides an example of an earthquake (1954) that was large enough to perhaps be judged the culminating event of the seismic cycle in a regionally important fault zone but that was followed instead by an even larger shock (1980). The space-time characteristics of the episode are unusual enough that they cannot represent the most likely mode of strain release on reverse-fault systems in general, but the episode should be viewed as one possible scenario for the evolution of seismicity on other such fault systems. RP DEWEY, JW (reprint author), US GEOL SURVEY,DENVER FED CTR,STOP 967,DENVER,CO 80225, USA. NR 43 TC 11 Z9 11 U1 0 U2 0 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD APR PY 1991 VL 81 IS 2 BP 446 EP 467 PG 22 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FF669 UT WOS:A1991FF66900008 ER PT J AU BRYAN, CJ JOHNSON, CE AF BRYAN, CJ JOHNSON, CE TI BLOCK TECTONICS OF THE ISLAND OF HAWAII FROM A FOCAL MECHANISM ANALYSIS OF BASAL SLIP SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID KILAUEA-VOLCANO; KALAPANA EARTHQUAKE; SEISMIC REFRACTION; CRUSTAL STRUCTURE; SOUTHEAST FLANK; 1975 KALAPANA; NOVEMBER 29; MAUNA-LOA; MODEL; MAGMA AB The southern third of the island of Hawaii is composed of at least three rigid blocks: Kilauea Volcano's south flank, Mauna Loa Volcano's southeast flank, and Mauna Loa Volcano's west flank. Analysis of earthquake focal mechanisms suggests that Kilauea's south flank, the most mobile of these blocks, is moving seaward perpendicular to its east rift zone along a southeasterly course at an azimuth of 155 +/- 5-degrees. Mauna Loa's southeastern flank is also moving in a southeasterly direction, although at a slightly more easterly azimuth of 140 +/- 5-degrees. Although data are sparse on the western flank of Mauna Loa due to low seismicity and inadequate seismic network station density, the available data suggest that this region is translating seaward along a generally westerly azimuth. Relative differences in these translational azimuths may represent oblique opening across the boundaries between these regions, the active rift zones of Kilauea and Mauna Loa Volcanoes. C1 US GEOL SURVEY,HAWAIIAN VOLCANO OBSERV,HAWAII NATL PK,HI 96718. RP BRYAN, CJ (reprint author), UNIV HAWAII,DEPT GEOL & GEOPHYS,HONOLULU,HI 96822, USA. NR 32 TC 21 Z9 21 U1 0 U2 1 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD APR PY 1991 VL 81 IS 2 BP 491 EP 507 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FF669 UT WOS:A1991FF66900010 ER PT J AU MORI, J AF MORI, J TI ESTIMATES OF VELOCITY STRUCTURE AND SOURCE DEPTH USING MULTIPLE P-WAVES FROM AFTERSHOCKS OF THE 1987 ELMORE RANCH AND SUPERSTITION HILLS, CALIFORNIA, EARTHQUAKES SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID IMPERIAL-VALLEY REGION; 24 NOVEMBER 1987; SYNTHETIC SEISMOGRAMS AB Event record sections, which are constructed by plotting seismograms from many closely spaced earthquakes recorded on a few stations, show multiple free-surface reflections (PP, PPP, PPPP) of the P wave in the Imperial Valley, California. The relative timing of these arrivals is used to estimate the strength of the P-wave velocity gradient within the upper 5 km of the sediment layer. Consistent with previous studies, a velocity model with a value of 1.8 km/sec at the surface increasing linearly to 5.8 km/sec at a depth of 5.5 km fits the data well. The relative amplitudes of the P and PP arrivals are used to estimate the source depth for the aftershock distributions of the Elmore Ranch and Superstition Hills main shocks. Although the depth determination has large uncertainties, both the Elmore Ranch and Superstition Hills aftershock sequences appear to have similar depth distribution in the range of 4 to 10 km. RP MORI, J (reprint author), US GEOL SURVEY,525 S WILSON AVE,PASADENA,CA 91106, USA. NR 17 TC 9 Z9 17 U1 3 U2 3 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD APR PY 1991 VL 81 IS 2 BP 508 EP 523 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FF669 UT WOS:A1991FF66900011 ER PT J AU CLAGUE, DA MOORE, JG AF CLAGUE, DA MOORE, JG TI GEOLOGY AND PETROLOGY OF MAHUKONA VOLCANO, HAWAII SO BULLETIN OF VOLCANOLOGY LA English DT Article AB The submarine Mahukona Volcano, west of the island of Hawaii, is located on the Loa loci line between Kahoolawe and Hualalai Volcanoes. The west rift zone ridge of the volcano extends across a drowned coral reef at about - 1150 m and a major slope break at about - 1340 m, both of which represent former shorelines. The summit of the volcano apparently reached to about 250 m above sea level (now at - 1100 m depth) and was surmounted by a roughly circular caldera. A second rift zone probably extended toward the east or southeast, but is completely covered by younger lavas from the adjacent subaerial volcanoes. Samples were recovered from nine dredges and four submersible dives. Using subsidence rates and the compositions of flows which drape the dated shoreline terraces, we infer that the voluminous phase of tholeiitic shield growth ended about 470 ka, but tholeiitic eruptions continued until at least 435 ka. Basalt, transitional between tholeiitic and alkalic basalt, erupted at the end of tholeiitic volcanism, but no postshield-alkalic stage volcanism occurred. The summit of the volcano apparently subsided below sea level between 435 and 365 ka. The tholeiitic lavas recovered are compositionally diverse. RP CLAGUE, DA (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 0 TC 25 Z9 25 U1 0 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0258-8900 J9 B VOLCANOL JI Bull. Volcanol. PD APR PY 1991 VL 53 IS 3 BP 159 EP 172 DI 10.1007/BF00301227 PG 14 WC Geosciences, Multidisciplinary SC Geology GA FK555 UT WOS:A1991FK55500001 ER PT J AU PARRISH, DL MARGRAF, FJ AF PARRISH, DL MARGRAF, FJ TI PREY SELECTIVITY BY AGE 0 WHITE PERCH (MORONE-AMERICANA) AND YELLOW PERCH (PERCA-FLAVESCENS) IN LABORATORY EXPERIMENTS SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID SIZE; PREFERENCE; LAKE; FRY AB We conducted prey selectivity experiments by age 0 white perch (Morone americana) and yellow perch (Perca flavescens) in the laboratory. Lake Erie zooplankters were introduced into tanks where both fishes were in single and combined species assemblages. We identified and counted the introduced plankton samples and the contents of fish stomachs after the feeding period. Our results showed no differences in prey consumed within a fish species, whether in single or combined assemblages (ANOVA, p > 0.05). There were a few differences between white perch and yellow perch consumption of each prey taxa (ANOVA); however, the arrays of organisms eaten were not different (MANOVA, p > 0.01). We note that the majority of prey consumed were smaller taxa, which is counter to optimal foraging predictions in relation to prey size, but is consistent with other research on young planktivore prey selectivities. C1 US FISH & WILDLIFE SERV,OHIO COOPERAT FISH & WILDLIFE RES UNIT,COLUMBUS,OH 43210. NR 16 TC 12 Z9 12 U1 1 U2 4 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD APR PY 1991 VL 48 IS 4 BP 607 EP 610 PG 4 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA FF520 UT WOS:A1991FF52000011 ER PT J AU HELLGREN, EC VAUGHAN, MR GWAZDAUSKAS, FC WILLIAMS, B SCANLON, PF KIRKPATRICK, RL AF HELLGREN, EC VAUGHAN, MR GWAZDAUSKAS, FC WILLIAMS, B SCANLON, PF KIRKPATRICK, RL TI ENDOCRINE AND ELECTROPHORETIC PROFILES DURING PREGNANCY AND NONPREGNANCY IN CAPTIVE FEMALE BLACK BEARS SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID PLASMA PROGESTERONE LEVELS; WESTERN SPOTTED SKUNK; URSUS-AMERICANUS; ESTROUS-CYCLE; PSEUDOPREGNANCY; IMPLANTATION; PARTURITION; MARITIMUS; ESTRADIOL; ESTRUS AB We collected blood samples from captive adult female black bears (Ursus americanus) at 10-day intervals during September-March in 1987-1988 and 1988-1989 (6 bears/year) in Virginia. Ten of 12 bears hibernated for an average of 92 days. Serum progesterone concentrations slowly increased from 2 to 7 ng/mL during October and November, then increased 2- to 3-fold 58 +/- 5 days before parturition in five bears that produced cubs. After the implantation peak, progesterone gradually declined, reaching undetectable levels 1-2 days postpartum. Similar but more variable progesterone profiles were observed in five of seven bears that did not produce any observed cubs. Progesterone was also assayed in 38 active wild black bears to relate to reproductive status in the den. Results suggested that pseudopregnancy, implantation failure, or fetal resorption may occur in black bears. Mean serum estradiol-17-beta concentrations were 18.5 +/- 0.7 (SE) pg/mL in captive bears, with pregnant bears showing no change between implantation and parturition. Polyacrylamide gel electrophoresis of serum proteins was not a reliable indicator of pregnancy. C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT FISHERIES & WILDLIFE SCI,BLACKSBURG,VA 24061. US FISH & WILDLIFE SERV,VIRGINIA COOPERAT FISH & WILDLIFE RES UNIT,BLACKSBURG,VA 24061. VIRGINIA POLYTECH INST & STATE UNIV,DEPT DAIRY SCI,BLACKSBURG,VA 24061. OI Hellgren, Eric/0000-0002-3870-472X NR 29 TC 16 Z9 16 U1 0 U2 8 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD APR PY 1991 VL 69 IS 4 BP 892 EP 898 DI 10.1139/z91-134 PG 7 WC Zoology SC Zoology GA FP798 UT WOS:A1991FP79800011 ER PT J AU HESTBECK, JB NICHOLS, JD MALECKI, RA AF HESTBECK, JB NICHOLS, JD MALECKI, RA TI ESTIMATES OF MOVEMENT AND SITE FIDELITY USING MARK RESIGHT DATA OF WINTERING CANADA GEESE SO ECOLOGY LA English DT Article DE BRANTA-CANADENSIS; CANADA GOOSE; MARK-RESIGHT DATA; MOVEMENT RATES; NECK BANDS; SITE FIDELITY; WINTER DISTRIBUTION ID SOCIAL FENCE HYPOTHESIS; POPULATION REGULATION; SURVIVAL RATES; DISTRIBUTION PATTERNS; CYCLIC MAMMALS; BAND-RECOVERY; DEMOGRAPHY; MIGRATION; MODELS AB Population ecologists have devoted disproportionate attention to the estimation and study of birth and death rates and far less effort to rates of movement. Movement and fidelity to wintering areas have important ecological and evolutionary implications for avian populations. Previous inferences about movement among and fidelity to wintering areas have been restricted by limitations of data and methodology. We use multiple observation data from a large-scale capture-resighting study of Canada Geese in the Atlantic flyway to estimate probabilities of returning to previous wintering locations and moving to new locations. Mark-resight data from 28 849 Canada Geese (Branta canadensis) banded with individually coded neck bands in the mid-Atlantic (New York, Pennsylvania, New Jersey), Chesapeake (Delaware, Maryland, Virginia), and Carolinas (North and South Carolina) were used to estimate movement and site fidelity. Two three-sample mark-resight models were developed and programmed using SURVIV to estimate the probability of moving among or remaining within these three wintering regions. The model (MV2) that incorporated "tradition" or memory of previous wintering regions fit the data better than the model (MV1) that assumes that a first-order Markov chain described movement among regions. Considerable levels of movement occurred among regions of the Atlantic flyway. The annual probability of remaining in the same region for two successive winters, used as a measure of site fidelity, was 0.710 +/- 0.016 (estimated mean +/- SE [SE], 0.889 +/- 0.006, and 0.562 +/- 0.025, for the mid-Atlantic, Chesapeake, and Carolinas, respectively. The estimated probability of moving to the Chesapeake from the mid-Atlantic or from the Carolinas was 3 x and 25 x as high, respectively, as the probability of moving in the opposite directions. Changes in estimated probabilities of moving between years corresponded to changes in winter harshness. In warm years, geese moved north and in cold years, they moved south. Geese had a high probability of moving to and remaining in the Chesapeake. Annual changes in the movement probabilities did not correspond to annual changes in the United States Fish and Wildlife Service midwinter survey. Considerable numbers of geese from the Carolinas appeared to be wintering in more northerly locations ("short-stopped") in subsequent winters. C1 CORNELL UNIV,US FISH & WILDLIFE SERV,NEW YORK COOPERAT FISH & WILDLIFE RES UNIT,ITHACA,NY 14853. RP HESTBECK, JB (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 51 TC 339 Z9 351 U1 14 U2 54 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9658 J9 ECOLOGY JI Ecology PD APR PY 1991 VL 72 IS 2 BP 523 EP 533 DI 10.2307/2937193 PG 11 WC Ecology SC Environmental Sciences & Ecology GA FE248 UT WOS:A1991FE24800011 ER PT J AU DECOLA, L AF DECOLA, L TI FRACTAL ANALYSIS OF MULTISCALE SPATIAL AUTOCORRELATION AMONG POINT DATA SO ENVIRONMENT AND PLANNING A LA English DT Article ID SCALE RP DECOLA, L (reprint author), US GEOL SURVEY,521 NATL CTR,RESTON,VA 22092, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 50 TC 2 Z9 2 U1 0 U2 0 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON, ENGLAND NW2 5JN SN 0308-518X J9 ENVIRON PLANN A JI Environ. Plan. A PD APR PY 1991 VL 23 IS 4 BP 545 EP 556 PG 12 WC Environmental Studies; Geography SC Environmental Sciences & Ecology; Geography GA FM405 UT WOS:A1991FM40500006 ER PT J AU CHIOU, CT KILE, DE RUTHERFORD, DW AF CHIOU, CT KILE, DE RUTHERFORD, DW TI THE NEUTRAL OIL IN COMMERCIAL LINEAR ALKYLBENZENESULFONATE AND ITS EFFECT ON ORGANIC SOLUTE SOLUBILITY IN WATER SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID LONG-CHAIN ALKYLBENZENES; HUMIC MATERIALS; SEWAGE-SLUDGE; DDT; ENHANCEMENTS AB Apparent water solubilities of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT), 2,4,5,2',5'-pentachlorobiphenyl (PCB), and 1,2,3-trichlorobenzene (TCB) were determined at room temperature in aqueous solutions of commercial linear alkylbenzenesulfonate (LAS), oil-free (solvent-extracted) LAS, and single-molecular 4-dodecylbenzenesulfonate. The extent of solute solubility enhancement by commercial LAS is markedly greater than that by other ionic surfactants below the measured critical micelle concentration (CMC); above the CMC, the enhancement data with LAS are comparable with other surfactants as micelles. The small amount of neutral oils in commercial LAS (1.7%), comprising linear alkylbenzenes (LABs) and bis(alkylphenyl) sulfones, contributes significantly to the enhanced solubility of DDT and PCB below the CMC; the effect is ascribed to formation of oil-surfactant emulsions. The oil-surfactant emulsion formed corresponds to approximately 9-10% of the commercial LAS below the CMC. The data suggest that discharge of wastewater containing a significant level of oils and surface-active agents could lead to potential mobilization of organic pollutants and LABs in aquatic environments. RP CHIOU, CT (reprint author), US GEOL SURVEY,DENVER FED CTR,DIV WATER RESOURCES,BOX 25046,MS 408,DENVER,CO 80225, USA. RI Chiou, Cary/C-3203-2013 NR 25 TC 18 Z9 18 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD APR PY 1991 VL 25 IS 4 BP 660 EP 665 DI 10.1021/es00016a008 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA FE652 UT WOS:A1991FE65200016 ER PT J AU SVERJENSKY, DA HEMLEY, JJ DANGELO, WM AF SVERJENSKY, DA HEMLEY, JJ DANGELO, WM TI THERMODYNAMIC ASSESSMENT OF HYDROTHERMAL ALKALI FELDSPAR-MICA-ALUMINOSILICATE EQUILIBRIA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID PARTIAL MOLAL PROPERTIES; ROCK-FORMING MINERALS; HIGH-PRESSURES; TRANSPORT-PROPERTIES; LOW ALBITE; TEMPERATURES; QUARTZ; UNCERTAINTIES; ELECTROLYTES; SOLUBILITY AB The thermodynamic properties of minerals retrieved from consideration of solid-solid and dehydration equilibria with calorimetric reference values, and those of aqueous species derived from studies of electrolytes, are not consistent with experimentally measured high-temperature solubilities in the systems K2O- and Na2O-Al2O3-SiO2-H2O-HCl (e.g., K-fs - Ms - Qtz - K+ - H+). This introduces major inaccuracies into the computation of ionic activity ratios and the acidities of diagenetic, metamorphic, and magmatic hydrothermal fluids buffered by alkali silicate-bearing assemblages. We report a thermodynamic analysis of revised solubility equilibria in these systems that integrates the thermodynamic properties of minerals obtained from phase equilibria studies (BERMAN, 1988) with the properties of aqueous species calculated from a calibrated equation of state (SHOCK and HELGESON, 1988). This was achieved in two separate steps. First, new values of the free energies and enthalpies of formation at 25-degrees-C and 1 bar for the alkali silicates muscovite and albite were retrieved from the experimental solubility equilibria at 300-degrees-C and P(sat). Because the latter have stoichiometric reaction coefficients different from those for solid-solid and dehydration equilibria, our procedure preserves exactly the relative thermodynamic properties of the alkali-bearing silicates (BERMAN, 1988). Only simple arithmetic adjustments of -1,600 and -1,626 (+/- 500) cal/mol to all the K- and Na-bearing silicates, respectively, in BERMAN (1988) are required. In all cases, the revised values are within +/- 0.2% of calorimetric values. Similar adjustments were derived for the properties of minerals from HELGESON et al. (1978). Second, new values of the dissociation constant of HCl were retrieved from the solubility equilibria at temperatures and pressures from 300-600-degrees-C and 0.5-2.0 kbars using a simple model for aqueous speciation. The results agree well with the conductance-derived dissociation constants from FRANCK (1956a,b) for temperatures from 300-550-degrees-C. Compared to the conductance-derived results of FRANTZ and MARSHALL (1984), our dissociation constants agree well at the highest densities, but are greater at lower densities. At the lowest density, at 600-degrees-C and 1 kbar, the discrepancy of 0.9 log units is within the overall uncertainties associated with our experimental results and those associated with deriving dissociation constants from conductance measurements in highly associated solutions (OELKERS and HELGESON, 1988). Finally, we also report an equation of state fit to the standard thermodynamic properties of the aqueous HCl molecule that is consistent with a wide array of independently determined dissociation constants of HCl and permits interpolation and extrapolation of the dissociation constant of HCl to 1000-degrees-C and 5.0 kbars. C1 US GEOL SURVEY,NATL CTR 959,RESTON,VA 22092. RP SVERJENSKY, DA (reprint author), JOHNS HOPKINS UNIV,DEPT EARTH & PLANETARY SCI,BALTIMORE,MD 21218, USA. RI Sverjensky, Dimitri/A-4612-2017 NR 48 TC 164 Z9 168 U1 1 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD APR PY 1991 VL 55 IS 4 BP 989 EP 1004 DI 10.1016/0016-7037(91)90157-Z PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FH322 UT WOS:A1991FH32200006 ER PT J AU TEQUI, C ROBIE, RA HEMINGWAY, BS NEUVILLE, DR RICHET, P AF TEQUI, C ROBIE, RA HEMINGWAY, BS NEUVILLE, DR RICHET, P TI MELTING AND THERMODYNAMIC PROPERTIES OF PYROPE (MG3AL2SI3O12) SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID TEMPERATURE HEAT-CAPACITIES; GLASS; CALORIMETRY; ANORTHITE; MINERALS; DIOPSIDE; 1000-K; 1800-K AB The heat capacity of Mg3Al2SiO12 glass has been measured from 10 to 1000 K by adiabatic and differential scanning calorimetry. The heat capacity of crystalline pyrope has been determined from drop-calorimetry measurements between 820 and 1300 K. From these and previously published results a consistent set of thermodynamic data is presented for pyrope and Mg3Al2Si3O12 glass and liquid for the interval 0-2000 K. The enthalpy of fusion at 1570 +/- 30 K, the metastable congruent 1-bar melting point, is 241 +/- 12 kJ/mol. C1 US GEOL SURVEY,NATL CTR 959,RESTON,VA 22092. RP TEQUI, C (reprint author), INST PHYS GLOBE,4 PL JUSSIEU,F-75252 PARIS 05,FRANCE. NR 27 TC 35 Z9 35 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD APR PY 1991 VL 55 IS 4 BP 1005 EP 1010 DI 10.1016/0016-7037(91)90158-2 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FH322 UT WOS:A1991FH32200007 ER PT J AU BROUXEL, M TATSUMOTO, M AF BROUXEL, M TATSUMOTO, M TI THE ESTHERVILLE MESOSIDERITE - U-PB, RB-SR, AND SM-ND ISOTOPIC STUDY OF A POLYMICT BRECCIA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID STONY-IRON METEORITES; CHONDRITES; HISTORY; RATES AB A systematic U-Pb, Sm-Nd, and Rb-Sr isotopic study shows that the Estherville mesosiderite was formed between 4.56 and 4.43 Ga. Observed isotopic heterogeneity is in agreement with multiple generations of meteoritic impacts described in other mesosiderites. At least part of the Estherville silicate fraction was formed early in solar system history as indicated by the Pb-Pb (4555 +/- 35 Ma), U-Pb (4560 +/- 31 Ma), Rb-Sr (4542 +/- 203 Ma), and Sm-Nd (4533 +/- 94 Ma) ages. Mesosiderites therefore present not only petrological but also geochronological similarities with eucrites. The Pb isotopic composition of the metal phase plots on the same isochron as the silicates, indicating formation and subsequent mixing with silicates early in the history of the solar system. This is consistent with previous observations indicating that iron was reduced during the silicate-magmatic stage, most likely a consequence of mixing with metal. In addition to these more-ancient portions of the Estherville breccia, other parts were formed later as suggested by the Pb-Pb (4422 +/- 50 Ma) and U-Pb (4437 +/- 11 Ma) ages observed in a second group of leaches and residues. This age is similar to some cumulate eucrite ages and may represent the formation of a second mesosiderite component. The Sm-Nd and the Rb-Sr ages obtained on Estherville show large errors that may be a consequence of the mixing between the 4.56 and 4.43 Ga endmembers. Estherville, like most mesosiderites, was affected by a major heating event around 3.5-3.7 Ga as shown by the Ar-Ar ages (BOGARD et al., 1990). This heating event partially disturbed the Rb-Sr isotopic system (Rb-Sr metamorphic ages range between 3.81 and 4.08 Ga). C1 US GEOL SURVEY,ISOTOPE GEOL BRANCH,DENVER,CO 80225. NR 47 TC 23 Z9 23 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD APR PY 1991 VL 55 IS 4 BP 1121 EP 1133 DI 10.1016/0016-7037(91)90167-4 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FH322 UT WOS:A1991FH32200016 ER PT J AU TURNER, CE FISHMAN, NS AF TURNER, CE FISHMAN, NS TI JURASSIC LAKE TOODICHI - A LARGE ALKALINE, SALINE LAKE, MORRISON FORMATION, EASTERN COLORADO PLATEAU SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article ID GULF-COAST; BURIAL DIAGENESIS; CLAY-MINERALS; SANDSTONES; ALBITIZATION; GEOCHEMISTRY; SEDIMENTS; TERTIARY; TEXAS AB A large alkaline, saline lake, Lake T'oo'dichi', occupied the entire eastern part of the Colorado Plateau region during deposition of the Brushy Basin Member of the Upper Jurassic Morrison Formation. The lake extended from near the site of Albuquerque, New Mexico, to near the site of Grand Junction, Colorado, and occupied a region that encompassed the San Juan and ancestral Paradox basins, making it the largest ancient alkaline, saline lake known. The lake was typically shallow and frequently evaporated to dryness, although the water table was probably never far beneath the surface. Intermittent streams carried detritus from source areas to the west and southwest far out into the lake basin, a reflection of a low depositional gradient and the ephemeral nature of the lake. Prevailing westerly winds carried silicic volcanic ash to the lake basin from an arc region to the west and southwest. A lateral hydrogeochemical gradient, characterized by increasing salinity and alkalinity from the margin of the lake to the center, developed in pore waters of the lacustrine sediments and resulted in alteration of the ash to a variety of authigenic minerals that define concentric zones within the lake basin. The basinward progression of diagenetic mineral zones is smectite --> clinoptilolite --> analcime +/- potassium feldspar --> albite. A concomitant lateral zonation of mixed-layer illite/smectite developed, from highly smectitic in the outermost zones to highly illitic in the central zone. Authigenic albite and illitic mixed-layer clay, minerals previously thought to require elevated temperatures for formation, crystallized during early diagenesis at syndepositional temperatures in the lacustrine sediments of Lake T'oo'dichi'. This study presents evidence for a syndepositional origin for both of these minerals. These findings have important implications in terms of limiting the use of these minerals as geothermometers. Recognition of alkaline, saline-lake deposits in the Morrison Formation significantly alters interpretations of depositional environments of this formation, and it also has important implications for paleoclimatic interpretation. Late Jurassic climate was apparently much more arid than had previously been thought. In fact, sedimentologic evidence suggests that the lake basin was typically dry for extended periods and enjoyed only brief wet intervals. This conclusion has important consequences for environmental interpretation of the habitat that was favorable for large herbivorous dinosaurs, which thrived in the Late Jurassic. RP TURNER, CE (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 939,DENVER,CO 80225, USA. NR 61 TC 83 Z9 85 U1 1 U2 12 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD APR PY 1991 VL 103 IS 4 BP 538 EP 558 DI 10.1130/0016-7606(1991)103<0538:JLTODA>2.3.CO;2 PG 21 WC Geosciences, Multidisciplinary SC Geology GA FE845 UT WOS:A1991FE84500009 ER PT J AU BEHRENDT, JC COOPER, A AF BEHRENDT, JC COOPER, A TI EVIDENCE OF RAPID CENOZOIC UPLIFT OF THE SHOULDER ESCARPMENT OF THE CENOZOIC WEST ANTARCTIC RIFT SYSTEM AND A SPECULATION ON POSSIBLE CLIMATE FORCING SO GEOLOGY LA English DT Article ID MOUNTAINS; HISTORY; UTAH AB The Cenozoic West Antarctic rift system, characterized by Cenozoic bimodal alkalic volcanic rocks, extends over a largely ice-covered area, from the Ross Sea nearly to the Bellingshausen Sea. It is bounded on one side by a spectacular 4- to 5-km-high rift-shoulder scarp (maximum bedrock relief 5 to 7 km) from northern Victoria Land-Queen Maud Mountains to the Ellsworth-Whitmore-Horlick Mountains. Jurassic tholeiites crop out with the late Cenozoic volcanic rocks along the section of the Transantarctic Mountains from northern Victoria Land to the Horlick Mountains. The Cenozoic rift shoulder diverges here from the Jurassic tholeiite trend, and the tholeiites are exposed discontinuously along the lower elevation (1-2 km) section of the Transantarctic Mountains to the Weddell Sea. Various lines of evidence, no one of which is independently conclusive, lead us (as others have also suggested) to interpret the following. The Transantarctic Mountains part of the rift shoulder (and probably the entire shoulder) has been rising since about 60 Ma, at episodic rates of approximately 1 km/m.y., most recently since mid-Pliocene time, rather than continuously at the mean rate of 100 m/m.y. Uplift rates vary along the scarp, which is cut transverse faults. We speculate that this uplift may have climatically forced the advance of the Antarctic ice sheet since the most recent warm period. We suggest a possible synergistic relation between episodic tectonism, mountain uplift, and volcanism in the Cenozoic West Antarctic rift system and waxing and waning of the Antarctic ice sheet beginning about earliest Oligocene time. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP BEHRENDT, JC (reprint author), US GEOL SURVEY,DENVER FED CTR,MS 964,BOX 25046,DENVER,CO 80225, USA. NR 56 TC 99 Z9 99 U1 0 U2 7 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD APR PY 1991 VL 19 IS 4 BP 315 EP 319 DI 10.1130/0091-7613(1991)019<0315:EORCUO>2.3.CO;2 PG 5 WC Geology SC Geology GA FE841 UT WOS:A1991FE84100007 ER PT J AU LEACH, DL PLUMLEE, GS HOFSTRA, AH LANDIS, GP ROWAN, EL VIETS, JG AF LEACH, DL PLUMLEE, GS HOFSTRA, AH LANDIS, GP ROWAN, EL VIETS, JG TI ORIGIN OF LATE DOLOMITE CEMENT BY CO2-SATURATED DEEP BASIN BRINES - EVIDENCE FROM THE OZARK REGION, CENTRAL UNITED-STATES SO GEOLOGY LA English DT Article ID DOLOMITIZATION; MISSOURI AB Studies of fluid inclusions in regionally extensive late dolomite cement (LDC) throughout the Ozark region show that CO2 effervescence was widespread during dolomite precipitation. On the basis of quantitative analyses of inclusion fluids, reaction-path modeling shows that LDC with trace amounts of sulfides can be deposited by effervescence of a CO2-saturated basin brine as it migrates to shallower levels and lower confining pressures. This precipitation mechanism best explains occurrences of LDC in the Ozark region and may account for LDC found in sedimentary basins worldwide. RP LEACH, DL (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,DENVER,CO 80225, USA. NR 26 TC 35 Z9 41 U1 0 U2 4 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD APR PY 1991 VL 19 IS 4 BP 348 EP 351 DI 10.1130/0091-7613(1991)019<0348:OOLDCB>2.3.CO;2 PG 4 WC Geology SC Geology GA FE841 UT WOS:A1991FE84100015 ER PT J AU PRINGLE, MS STAUDIGEL, H GEE, J AF PRINGLE, MS STAUDIGEL, H GEE, J TI JASPER SEAMOUNT - 7 MILLION YEARS OF VOLCANISM SO GEOLOGY LA English DT Article ID PACIFIC SEAMOUNTS; NONUNIFORM MAGNETIZATION; OCEANIC BASALTS; EVOLUTION; AGES; SYSTEM; RECORD; MANTLE; FIELD; MAGMA AB Jasper Seamount is a young, mid-sized (690 km3) oceanic intraplate volcano located about 500 km west-southwest of San Diego, California. Reliable Ar-40/Ar-39 age data were obtained for several milligram-sized samples of 4 to 10 Ma plagioclase by using a defocused laser beam to clean the samples before fusion. Gee and Staudigel suggested that Jasper Seamount consists of a transitional to tholeiitic shield volcano formed by flank transitional series lavas, overlain by flank alkalic series lavas and summit alkalic series lavas. Twenty-nine individual Ar-40/Ar-39 laser fusion analyses on nine samples confirm the stratigraphy: 10.3-10.0 Ma for the flank transitional series, 8.7-7.5 Ma for the flank alkalic series, and 4.8-4.1 Ma for the summit alkalic series. The alkalinity of the lavas clearly increases with time, and there appear to be 1 to 3 m.y. hiatuses between each series. The age data are consistent with the complex magnetic anomaly of Jasper; however, the dominant reversed polarity inferred from the anomaly suggests that most of the seamount formed at ca. 11 Ma, prior to the onset of Chron C5N. The duration of volcanism of Jasper Seamount is slightly longer than the duration of volcanism at Hawaiian volcanoes, suggesting that individual age data from seamounts may constrain the age of a seamount only to within about 7 m.y. unless the stage of volcanism can be unambiguously determined. Extrapolating from the results of our study, similar precision in age determinations should be possible on 50 mg of 1 Ma plagioclase from mid-ocean ridge basalt, opening new possibilities in the geochronology of young, low-potassium volcanic rocks. C1 SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. RP PRINGLE, MS (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 39 TC 24 Z9 24 U1 0 U2 1 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD APR PY 1991 VL 19 IS 4 BP 364 EP 368 DI 10.1130/0091-7613(1991)019<0364:JSSMYO>2.3.CO;2 PG 5 WC Geology SC Geology GA FE841 UT WOS:A1991FE84100019 ER PT J AU SANDBERG, CA GUTSCHICK, RC PETERSEN, MS POOLE, FG ZIEGLER, W AF SANDBERG, CA GUTSCHICK, RC PETERSEN, MS POOLE, FG ZIEGLER, W TI DELLE PHOSPHATIC MEMBER - AN ANOMALOUS PHOSPHATIC INTERVAL IN THE MISSISSIPPIAN (OSAGEAN-MERAMECIAN) SHELF SEQUENCE OF CENTRAL UTAH - COMMENT SO GEOLOGY LA English DT Note C1 US GEOL SURVEY,MEDFORD,OR 97504. BRIGHAM YOUNG UNIV,DEPT GEOL,PROVO,UT 84602. FORSCH INST SENCHENBERG,W-6000 FRANKFURT 1,GERMANY. RP SANDBERG, CA (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,DENVER,CO 80225, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD APR PY 1991 VL 19 IS 4 BP 410 EP 411 DI 10.1130/0091-7613(1991)019<0410:CARODP>2.3.CO;2 PG 2 WC Geology SC Geology GA FE841 UT WOS:A1991FE84100035 ER PT J AU NICHOLS, KM SILBERLING, NJ AF NICHOLS, KM SILBERLING, NJ TI DELLE PHOSPHATIC MEMBER - AN ANOMALOUS PHOSPHATIC INTERVAL IN THE MISSISSIPPIAN (OSAGEAN-MERAMECIAN) SHELF SEQUENCE OF CENTRAL UTAH - REPLY SO GEOLOGY LA English DT Note RP NICHOLS, KM (reprint author), US GEOL SURVEY,DENVER FED CTR,BOX 25046,DENVER,CO 80225, USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA PI BOULDER PA PO BOX 9140 3300 PENROSE PLACE, BOULDER, CO 80301 SN 0091-7613 J9 GEOLOGY JI Geology PD APR PY 1991 VL 19 IS 4 BP 411 EP 412 PG 2 WC Geology SC Geology GA FE841 UT WOS:A1991FE84100036 ER PT J AU DIBONA, M BOATWRIGHT, J AF DIBONA, M BOATWRIGHT, J TI SINGLE-STATION DECOMPOSITION OF SEISMOGRAMS FOR SUBEVENT TIME HISTORIES SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article; Proceedings Paper CT SYMP OF THE EUROPEAN GEOPHYSICAL SOC CY MAR 14-15, 1989 CL BARCELONA, SPAIN SP EUROPEAN GEOPHYS SOC DE COMPLEX EARTHQUAKES; GREEN FUNCTIONS; SEISMOGRAM DECOMPOSITION ID RADIATION; ENERGY AB We have adapted an iterative least-squares inversion with positivity constraints to the problem of deconvolving the recordings of a small earthquake from the recordings of a large composite earthquake. The inversion uses an F test to minimize the number of non-zero amplitudes or subevents in the solution set, by requiring each added subevent to reduce the variance significantly. We apply this inversion to the analysis of strong motion recording of a set of moderate-sized (4.0 less-than-or-equal-to M(L) less-than-or-equal-to 6.4) aftershocks of the 1976 Friuli earthquake. The earthquake pairs are selected by comparing S trigger times and polarization diagrams. The deconvolved time series are interpreted as the time history of slip events or stress release in the composite earthquake, depending on whether the recordings of the small earthquake are unfiltered or filtered to simulate the waveforms radiated by subevents. Deconvolving with the filtered recordings reduces the variance more rapidly, as a function of the number of subevents, than deconvolving with the unfiltered recordings. The deconvolved time series for three of the four earthquakes analysed indicate that the rupture processes resemble the failure of asperities where the initial subevent has the largest stress drop and the later subevents have longer durations and weaker stress drops. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP DIBONA, M (reprint author), INST NAZL GEOFIS,I-00161 ROME,ITALY. NR 14 TC 6 Z9 6 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0956-540X J9 GEOPHYS J INT JI Geophys. J. Int. PD APR PY 1991 VL 105 IS 1 BP 103 EP 117 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FF395 UT WOS:A1991FF39500010 ER PT J AU ANDERSON, WL AF ANDERSON, WL TI OPTIMIZED FAST HANKEL TRANSFORM FILTERS - COMMENT SO GEOPHYSICAL PROSPECTING LA English DT Note RP ANDERSON, WL (reprint author), US GEOL SURVEY,DENVER FED CTR,POB 25046,MAIL STOP 964,DENVER,CO 80225, USA. NR 5 TC 2 Z9 4 U1 0 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0016-8025 J9 GEOPHYS PROSPECT JI Geophys. Prospect. PD APR PY 1991 VL 39 IS 3 BP 445 EP 447 DI 10.1111/j.1365-2478.1991.tb00321.x PG 3 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FA887 UT WOS:A1991FA88700008 ER PT J AU MUELLER, RJ JOHNSTON, MJS LANGBEIN, JO AF MUELLER, RJ JOHNSTON, MJS LANGBEIN, JO TI POSSIBLE TECTONOMAGNETIC EFFECT OBSERVED FROM MID-1989, TO MID-1990, IN LONG VALLEY CALDERA, CALIFORNIA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MOUNT ST-HELENS; WASHINGTON; FIELD AB Precise measurements of local magnetic fields have been obtained with a differentially connected array of three proton magnetometers in the Long Valley caldera region since 1984. Two magnetometers are located inside the caldera with a third reference magnetometer located 26 km southeast of the caldera. After correction for secular variation, it is apparent that an anomalous 2 nT decrease in the magnetic field occurred from mid-1989 to mid-1990 at the magnetometer located closest to the center of the resurgent dome inside the caldera. During this period a significant increase in geodetic strain rate of 8.5 ppm/a was observed on the two-color geodimeter network within the caldera from October, 1989, to mid-1990 and a dramatic increase in seismic activity occurred from December, 1989 to July, 1990. A simple dilatational point-source model with pressure increasing by 52 Mpa from October 1989 to August 1990 at a depth of about 7 km beneath the center of the resurgent dome can be fit to the strain data. If this same model is used to calculate piezomagnetic fields in the caldera, the results obtained agree with the observed local magnetic field data provided the Curie point isotherm is at a depth of less-than-or-equal-to 5 km. Taken together, these magnetic, seismic and geodetic data suggest that an episode of active magmatic intrusion occurred from late 1989 to mid-1990 at a depth of about 7-8 km beneath the resurgent dome within the Long Valley caldera. Other indications of this intrusion should be evident in measurements of leveling, local gravity, and seismic imaging data. RP MUELLER, RJ (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 22 TC 5 Z9 5 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR PY 1991 VL 18 IS 4 BP 601 EP 604 DI 10.1029/91GL00814 PG 4 WC Geosciences, Multidisciplinary SC Geology GA FG828 UT WOS:A1991FG82800007 ER PT J AU BLANPIED, ML LOCKNER, DA BYERLEE, JD AF BLANPIED, ML LOCKNER, DA BYERLEE, JD TI FAULT STABILITY INFERRED FROM GRANITE SLIDING EXPERIMENTS AT HYDROTHERMAL CONDITIONS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID WESTERLY GRANITE; DEPTH; TEMPERATURE AB Seismicity on crustal faults is concentrated in the depth interval 1-3 to 12-15 km. Tse and Rice (1986) suggested that the lower bound on seismicity is due to a switch with increasing temperature from velocity weakening (destabilizing) to velocity strengthening (stabilizing) friction. They inferred this transition from friction data for dry granite; however, pore fluids exist at elevated temperatures throughout the crust, and may strongly influence strength and sliding behavior. We present new data from sliding experiments on granite at elevated T (23-degrees to 600-degrees) plus elevated P(H2O) (100 MPa). Our results show velocity strengthening at room temperature, but velocity weakening from 100-degrees to 350-degrees-C (except at 250-degrees). From 350-degrees to 600-degrees there are systematic trends from velocity weakening to strong velocity strengthening, and from high to low friction; neither trend was seen in tests on dry granite. The velocity dependence data imply the potential for unstable slip in the interval 100-degrees to 350-degrees. Using a geotherm to map temperature to depth, this interval closely matches the observed earthquake distribution. RP BLANPIED, ML (reprint author), US GEOL SURVEY,MS-977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 18 TC 188 Z9 194 U1 2 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR PY 1991 VL 18 IS 4 BP 609 EP 612 DI 10.1029/91GL00469 PG 4 WC Geosciences, Multidisciplinary SC Geology GA FG828 UT WOS:A1991FG82800009 ER PT J AU TREHU, A MORELALHUISSIER, P MEYER, R HAJNAL, Z KARL, J MEREU, R SEXTON, J SHAY, J CHAN, WK EPILI, D JEFFERSON, T SHIH, XR WENDLING, S MILKEREIT, B GREEN, A HUTCHINSON, D AF TREHU, A MORELALHUISSIER, P MEYER, R HAJNAL, Z KARL, J MEREU, R SEXTON, J SHAY, J CHAN, WK EPILI, D JEFFERSON, T SHIH, XR WENDLING, S MILKEREIT, B GREEN, A HUTCHINSON, D TI IMAGING THE MIDCONTINENT RIFT BENEATH LAKE-SUPERIOR USING LARGE APERTURE SEISMIC DATA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CRUSTAL STRUCTURE; PROFILES; SYSTEM AB We present a detailed velocity model across the 1.1 billion year old Midcontinent Rift System (MRS) in central Lake Superior. The model was derived primarily from onshore-offshore large-aperture seismic and gravity data. High velocities obtained within a highly reflective half-graben that was imaged on coincident seismic reflection data demonstrate the dominantly mafic composition of the graben fill and constrain its total thickness to be at least 30 km. Strong wide-angle reflections are observed from the lower crust and Moho, indicating that the crust is thickest (55-60 km) beneath the axis of the graben. The total crustal thickness decreases rapidly to about 40 km beneath the south shore of the lake and decreases more gradually to the north. Above the Moho is a high-velocity lower crust interpreted to result from syn-rift basaltic intrusion into and/or underplating beneath the Archean lower crust. The lower crust is thickest beneath the axis of the main rift half-graben. A second region of thick lower crust is found approximately 100 km north of the axis of the rift beneath a smaller half graben that is interpreted to reflect an earlier stage of rifting. The crustal model presented here resembles recent models of some passive continental margins and is in marked contrast to many models of both active and extinct Phanerozoic continental rift zones. It demonstrates that the Moho is a dynamic feature, since the pre-rift Moho is probably within or above the high-velocity lower crust, whereas the post-rift Moho is defined as the base of this layer. In the absence of major tectonic activity, however, the Moho is very stable, since the large, abrupt variations in crustal thickness beneath the MRS have been preserved for at least a billion years. C1 UNIV WISCONSIN,DEPT GEOPHYS,MADISON,WI 53705. UNIV SASKATCHEWAN,DEPT GEOL SCI,SASKATOON S7N 0W0,SASKATCHEWAN,CANADA. UNIV WISCONSIN,DEPT PHYS,OSHKOSH,WI 54901. UNIV WESTERN ONTARIO,DEPT GEOPHYS,LONDON N6A 5B7,ONTARIO,CANADA. SO ILLINOIS UNIV,DEPT GEOL,CARBONDALE,IL 62901. US GEOL SURVEY,WOODS HOLE,MA 02543. GEOL SURVEY CANADA,OTTAWA K1A 0Y3,ONTARIO,CANADA. RP TREHU, A (reprint author), OREGON STATE UNIV,OCEAN ADM BLDG 104,CORVALLIS,OR 97331, USA. NR 29 TC 28 Z9 28 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR PY 1991 VL 18 IS 4 BP 625 EP 628 DI 10.1029/91GL00826 PG 4 WC Geosciences, Multidisciplinary SC Geology GA FG828 UT WOS:A1991FG82800013 ER PT J AU KANE, JS AF KANE, JS TI DERIVATION OF RECOMMENDED VALUES - AN OPINION SO GEOSTANDARDS NEWSLETTER LA English DT Article ID ELEMENTAL CONCENTRATION DATA; COMPILATION REPORT; 1987 COMPILATION AB Two principal approaches are being used currently to develop reference samples used in geochemistry. The first is typified by work at The National Institute of Standards and Technology (NIST) to develop standard reference materials (SRMs) whose elemental concentrations are certified. All data is collected under stringent quality control (QC). Agreement between average results for replicated analyses (6 less-than-or-equal-to n < 20) obtained by two or more analysts using either a single, definitive method or independent methods of analysis is required for certification; a large number of laboratory/method average results is not. The United States Geological Survey (USGS), International Working Group (IWG), and others base recommended concentrations on larger sets of compiled data, which may or may not have been collected under similar conditions of QC. The derived recommended concentrations are updated periodically, on the assumption that recommended concentration quality improves as the size of the data base increases. That assumption is examined in this paper, and the general lack of statistically significant difference between original and updated concentration is demonstrated. RP KANE, JS (reprint author), US GEOL SURVEY,DEPT INTERIOR,MAIL STOP 923,RESTON,VA 22092, USA. NR 28 TC 7 Z9 7 U1 0 U2 0 PU GEOSTANDARDS PI VANDOEUVRE NANCY PA 15 RUE NOTRE-DAME-DES-PAUVRES BP 20, 54501 VANDOEUVRE NANCY, FRANCE SN 0150-5505 J9 GEOSTANDARD NEWSLETT JI Geostand. Newsl. PD APR PY 1991 VL 15 IS 1 BP 13 EP 21 DI 10.1111/j.1751-908X.1991.tb00091.x PG 9 WC Geosciences, Multidisciplinary SC Geology GA FJ243 UT WOS:A1991FJ24300003 ER PT J AU KANE, JS AF KANE, JS TI QUALITY-CONTROL AND REFERENCE SAMPLE DATA-BASES SO GEOSTANDARDS NEWSLETTER LA English DT Article ID RARE-EARTH ELEMENTS; GEOLOGICAL-MATERIALS; 1987 COMPILATION; SPECTROMETRY AB A critical aspect of any quality control program is the definition of criteria for "satisfactory" performance of analytical methods. These criteria should address both expected accuracy and expected precision of the methods, as well as any variation in these figures of merit from one sample type to another. Development of appropriate criteria and their application to analytical programs for the characterization of new reference samples is presented. RP KANE, JS (reprint author), US GEOL SURVEY,DEPT INTERIOR,MAIL STOP 923,RESTON,VA 22092, USA. NR 38 TC 12 Z9 12 U1 0 U2 0 PU GEOSTANDARDS PI VANDOEUVRE NANCY PA 15 RUE NOTRE-DAME-DES-PAUVRES BP 20, 54501 VANDOEUVRE NANCY, FRANCE SN 0150-5505 J9 GEOSTANDARD NEWSLETT JI Geostand. Newsl. PD APR PY 1991 VL 15 IS 1 BP 33 EP 42 DI 10.1111/j.1751-908X.1991.tb00093.x PG 10 WC Geosciences, Multidisciplinary SC Geology GA FJ243 UT WOS:A1991FJ24300005 ER PT J AU KLEIN, DR BAY, C AF KLEIN, DR BAY, C TI DIET SELECTION BY VERTEBRATE HERBIVORES IN THE HIGH ARCTIC OF GREENLAND SO HOLARCTIC ECOLOGY LA English DT Article ID FOOD AB Microhistological analysis of fecal droppings indicates that graminoids (sedges, grasses, and rushes) and the only willow present, Salix arctica, are primary food items of the muskox Ovibos moschatus, arctic hare Lepus arcticus, and collared lemming Dicrostonyx groenlandicus in northern Greenland (79-degrees-83-degrees-N). Plant biomass available during the peak growing season varied with vegetation types from < 2 g m-2 in polar barrens to 34 g m-2 in sedge fens. The clustered distribution of vegetation minimizes competition among vertebrate herbivores. C1 UNIV COPENHAGEN,BOT MUSEUM,DK-1123 COPENHAGEN K,DENMARK. RP KLEIN, DR (reprint author), UNIV ALASKA,US FISH & WILDLIFE SERV,ALASKA COOPERAT WILDLIFE RES UNIT,FAIRBANKS,AK 99775, USA. NR 11 TC 28 Z9 28 U1 3 U2 10 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0105-9327 J9 HOLARCTIC ECOL PD APR-JUN PY 1991 VL 14 IS 2 BP 152 EP 155 PG 4 WC Ecology SC Environmental Sciences & Ecology GA FH823 UT WOS:A1991FH82300011 ER PT J AU REES, TF LEENHEER, JA RANVILLE, JF AF REES, TF LEENHEER, JA RANVILLE, JF TI USE OF A SINGLE-BOWL CONTINUOUS-FLOW CENTRIFUGE FOR DEWATERING SUSPENDED SEDIMENTS - EFFECT ON SEDIMENT PHYSICAL AND CHEMICAL CHARACTERISTICS SO HYDROLOGICAL PROCESSES LA English DT Article DE CONTINUOUS FLOW CENTRIFUGE; SEDIMENTS; PARTICLE SIZE DISTRIBUTIONS; ELECTROPHORETIC MOBILITY; WATER SEDIMENT SEPARATIONS; SEDIMENT DEWATERING AB The use of a single-bowl continuous-flow centrifuge (CFC, Sharples-Pennwalt Model AS-12) for dewatering suspended sediment from large volumes of river water is evaluated. Sediment-recovery efficiency of 86-91 per cent is comparable to that of other types of CFC units. The recovery efficiency is limited by the particle-size distribution of the feed water and by the limiting particle diameter that is retained in the centrifuge bowl. The limiting particle diameter, using the parameters for this study (bowl radius = 10.5 cm; bowl length = 71.1 cm; rotational velocity = 16000 r min-1; flow rate = 2 L min-1, and an assumed hydrated particle density = 1.7 gm cm-3), is 370 nm. There seems to be no particle-size fractionation within the centrifuge bowl - the median particle size was the same at the top as at the bottom. Particle electrophoretic mobility plays some role in fractionation of particles within the centrifuge. The mobility ranged from -1.19 to -2.01 x 10(-8) m2 V-1 s-1, which is typical of clays coated with organic matter, the charge of which is partially neutralized by divalent cations and iron. Contamination by trace metals and organics is minimized by coating all surfaces that come in contact with the sample with either FEP or PFA Teflon and using a removable FEP Teflon liner in the centrifuge bowl. Because of the physical and chemical factors affecting particle fractionation within the centrifuge, care must be exercised in interpreting the environmental consequences of particles collected by continuous-flow centrifugation. RP REES, TF (reprint author), US GEOL SURVEY,5735 KEARNY VILLA RD,SUITE 0,SAN DIEGO,CA 92123, USA. RI Ranville, James/H-1428-2011; OI ranville, james/0000-0002-4347-4885 NR 0 TC 24 Z9 24 U1 0 U2 10 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0885-6087 J9 HYDROL PROCESS JI Hydrol. Process. PD APR-JUN PY 1991 VL 5 IS 2 BP 201 EP 214 DI 10.1002/hyp.3360050207 PG 14 WC Water Resources SC Water Resources GA FL492 UT WOS:A1991FL49200006 ER PT J AU ALLEY, WM WARMERDAM, PMM AF ALLEY, WM WARMERDAM, PMM TI INTERNATIONAL-CONFERENCE ON HYDROLOGICAL RESEARCH BASINS AND THE ENVIRONMENT - WAGENINGEN, THE NETHERLANDS, 24-28 SEPTEMBER 1990 SO HYDROLOGICAL SCIENCES JOURNAL-JOURNAL DES SCIENCES HYDROLOGIQUES LA English DT Editorial Material RP ALLEY, WM (reprint author), US GEOL SURVEY,RESTON,VA 22092, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IAHS PRESS, INST HYDROLOGY PI WALLINGFORD PA C/O SARAH CAGE, WALLINGFORD, ENGLAND OX10 8BB SN 0262-6667 J9 HYDROLOG SCI J JI Hydrol. Sci. J.-J. Sci. Hydrol. PD APR PY 1991 VL 36 IS 2 BP 181 EP 182 PG 2 WC Water Resources SC Water Resources GA FD958 UT WOS:A1991FD95800007 ER PT J AU JOHNSON, DH AF JOHNSON, DH TI FURTHER COMMENTS ON ESTIMATING NEST SUCCESS - COMMENT SO IBIS LA English DT Note ID RATES RP JOHNSON, DH (reprint author), US FISH & WILDLIFE SERV,NO PRAIRIE WILDLIFE CTR,JAMESTOWN,ND 58402, USA. NR 8 TC 11 Z9 11 U1 0 U2 1 PU BRITISH ORNITHOLOGISTS UNION PI TRING PA C/O NATURAL HISTORY MUSEUM, SUB-DEPT ORNITHOLOGY, TRING, HERTS, ENGLAND HP23 6AP SN 0019-1019 J9 IBIS JI Ibis PD APR PY 1991 VL 133 IS 2 BP 205 EP 207 PG 3 WC Ornithology SC Zoology GA FG502 UT WOS:A1991FG50200014 ER PT J AU RUPPERT, LF STANTON, RW CECIL, CB EBLE, CF DULONG, FT AF RUPPERT, LF STANTON, RW CECIL, CB EBLE, CF DULONG, FT TI EFFECTS OF DETRITAL INFLUX IN THE PENNSYLVANIAN UPPER FREEPORT PEAT SWAMP SO INTERNATIONAL JOURNAL OF COAL GEOLOGY LA English DT Article ID QUARTZ; COAL; CATHODOLUMINESCENCE; SILICA AB Quartz cathodoluminescence properties and mineralogy of three sets of samples and vegetal and/or miospore data from two sets of samples from the Upper Freeport coal bed, west-central Pennsylvania, show that detrital influence from a penecontemporaneous channel is limited to an area less than three km from the channel. The sets of samples examined include localities of the coal bed where (1) the coal is thin, split by partings, and near a penecontemporaneous fluvial channel, (2) the coal is relatively thick and located approximately three km from the channel, and (3) the coal is thick and located approximately 12 km from the channel. Samples from locality 1 (nearest the channel) have relatively high-ash yields (low-temperature ash average = 27.3% on a pyrite-and calcite-free basis) and high proportions of quartz and clay minerals. The quartz is primarily detrital, as determined by cathodoluminescent properties, and the ratio of kaolinite to illite is low. In addition, most of the plant remains and miospores indicate peat-forming plants that required low nutrient levels for growth. In contrast, samples from localities 2 and 3, from the more interior parts of the bed, contained predominantly authigenic quartz grains and yielded low-temperature ash values of less than 14% on a pyrite- and calcite-free basis. The low-temperature ash contains low concentrations of quartz and clay minerals and the ratio of kaolinite to illite is relatively high. Although intact core was not available for paleobotanical analyses, another core collected within 1 km from locality 3 contained plant types interpreted to have required high nutrient levels for growth. These data indicate that mineral formation is dominated by authigenic processes in interior parts of the coal body. Some of the authigenic quartz may have been derived from herbaceous ferns as indicated by patterns in the palynological and paleobotanical data. In contrast, detrital processes appeared to be limited to in areas directly adjacent to the penecontemporaneous channel where the coal bed is high in ash, split by mineral-rich partings, and of little or no economic value. RP RUPPERT, LF (reprint author), US GEOL SURVEY,COAL GEOL BRANCH,NATL CTR,MS 956,RESTON,VA 22092, USA. OI Ruppert, Leslie/0000-0002-7453-1061 NR 37 TC 20 Z9 20 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-5162 J9 INT J COAL GEOL JI Int. J. Coal Geol. PD APR PY 1991 VL 17 IS 2 BP 95 EP 116 DI 10.1016/0166-5162(91)90006-5 PG 22 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA FH223 UT WOS:A1991FH22300001 ER PT J AU DOUGLAS, AJ JOHNSON, RL AF DOUGLAS, AJ JOHNSON, RL TI AQUATIC HABITAT MEASUREMENT AND VALUATION - IMPUTING SOCIAL BENEFITS TO INSTREAM FLOW LEVELS SO JOURNAL OF ENVIRONMENTAL MANAGEMENT LA English DT Article DE CONFLICT RESOLUTION; WATER ALLOCATION; INSTREAM FLOW; ECONOMIC ANALYSIS ID RIVER RP DOUGLAS, AJ (reprint author), US FISH & WILDLIFE SERV, NATL ECOL RES CTR, 2627 REDWING RD, FT COLLINS, CO 80526 USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0301-4797 EI 1095-8630 J9 J ENVIRON MANAGE JI J. Environ. Manage. PD APR PY 1991 VL 32 IS 3 BP 267 EP 280 DI 10.1016/S0301-4797(05)80057-X PG 14 WC Environmental Sciences SC Environmental Sciences & Ecology GA FH847 UT WOS:A1991FH84700007 ER PT J AU GRACZYK, DJ SONZOGNI, WC AF GRACZYK, DJ SONZOGNI, WC TI REDUCTION OF DISSOLVED-OXYGEN CONCENTRATION IN WISCONSIN STREAMS DURING SUMMER RUNOFF SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article AB It is commonly beleived that runoff from heavy rainfall is not detrimental to the O content of rural streams free from industrial and municipal discharges. However, evidence is presented of low dissolved O (DO) concentrations during high flows (caused by agricultural runoff during summer rainstorms) in southern Wisconsin streams. Continuous monitoring of streams with in situ oxygen meters indicated a rapid decrease in dissolved oxygen with a rise in the hydrograph. The cause of the oxygen reduction may be due to one or more factors such as (i) inflow of large volumes of runoff with low DO concentrations, (ii) the influx or resuspension of O demanding materials as a result of the storm water input, (iii) decreased O solubility caused by increased water temperature, and (iv) possible reduced photosynthetic productivity. Loss of DO is important because it appears to be associated with fish kills and declining sport fish populations in streams in the region. C1 UNIV WISCONSIN,WATER CHEM PROGRAM,HYG & CIVIL & ENVIRONM ENGN LAB,MADISON,WI 53706. RP GRACZYK, DJ (reprint author), US GEOL SURVEY,6417 NORMANDY LANE,MADISON,WI 53719, USA. NR 30 TC 12 Z9 12 U1 2 U2 8 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD APR-JUN PY 1991 VL 20 IS 2 BP 445 EP 451 PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA FK179 UT WOS:A1991FK17900018 ER PT J AU OATFIELD, WJ CZARNECKI, JB AF OATFIELD, WJ CZARNECKI, JB TI HYDROGEOLOGIC INFERENCES FROM DRILLERS LOGS AND FROM GRAVITY AND RESISTIVITY SURVEYS IN THE AMARGOSA DESERT, SOUTHERN NEVADA SO JOURNAL OF HYDROLOGY LA English DT Article AB The Amargosa Desert of southern Nevada, in the Basin and Range province, is hydraulically downgradient from Yucca Mountain, the potential site of a respository for high-level nuclear waste. Groundwater flow paths and flow rates beneath the Amargosa Desert are controlled in part by the total saturated thickness and the hydraulic properties of basin-fill alluvial sediments. Drillers' logs of water wells completed in alluvium were analyzed to help characterize the hydrogeologic framework underlying the Amargosa Desert. Fractions of coarse-grained sediments, calculated from each of these logs, were contoured using a universal-kriging routine to interpolate values. Results from a previous electrical sounding survey also were contoured, including the estimated depth to Paleozoic (?) basement rocks. The vertical electric sounding results were obtained from individual depth-to-resistivity profiles, from which the average resistivity of the total profile and the resistivity of the upper 75 m were calculated. The distribution and variations in average resistivity of the total depth correlated reasonably well with the distribution of variations in regional gravity. Patterns of contours of the resistivity of the upper 75 m of alluvium were similar to patterns of regional contours of the predominant cation (sodium) in ground water. Gravity lows correspond in some places to the presence of lacustrine, eolian, or marsh surface deposits, which may function as barriers to groundwater flow. Gravity lows also correspond to areas with thick basin-fill sediments, which was corroborated by depth-to-basement data determined from vertical electric soundings. Depths to Paleozoic (?) basement rocks may be as much as 1600 m based on data from the resistivity survey, which were corroborated in part by seismic-refraction survey data. Small variations exist in the percentage of the basin fill that is saturated. The unsaturated zone is always < 15% of the alluvial column. Analysis of depth-to-water and hydrochemical data, in conjunction with average resistivity data for the upper 75 m of alluvium, suggest a hydrologic barrier near the center of the Amargosa Desert. RP OATFIELD, WJ (reprint author), US GEOL SURVEY,POB 25046,MAIL STOP 421,DENVER,CO 80225, USA. NR 18 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD APR PY 1991 VL 124 IS 1-2 BP 131 EP 158 DI 10.1016/0022-1694(91)90010-F PG 28 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA FH589 UT WOS:A1991FH58900008 ER PT J AU KEITH, TEC AF KEITH, TEC TI FOSSIL AND ACTIVE FUMAROLES IN THE 1912 ERUPTIVE DEPOSITS, VALLEY OF 10,000 SMOKES, ALASKA SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article ID KATMAI-NATIONAL-PARK; THOUSAND-SMOKES; FLOW; TUFF AB Fumaroles in the ash-flow sheet emplaced during the 1912 eruption of Novarupta were intensely active throughout the Valley of Ten Thousand Smokes (VTTS) when first studied in 1917. Fumarole temperatures recorded in 1919 were as hot as 645-degrees-C. Influx of surface waters into the hot ash-flow sheet provided the fluid flow to sustain the fumaroles but also enchanced cooling so that by the mid-1930's vigorous activity survived only in the vent region. Configuration and distribution of high-temperature fissure fumaroles tens of meters long, that are prevalent in the middle and upper VTTS, were controlled largely by sintering and degree of welding, which in turn controlled fracturing and permeability of the ash-flow tuff. One fracture type developed parallel to the enclosing valley walls during compaction of the ash-flow sheet. Another type extends across the VTTS nearly perpendicular to the flow direction. A third type of randomly oriented fractures developed as cooling contraction cracks during vapor-phase devitrification. In distal parts of the ash-flow sheet where the tuff is nonwelded, prominent fumaroles have irregular funnel-shaped morphologies. Fumarole distribution in the nonwelded part of the ash-flow sheet is concentrated above pre-emplacement river channels. The hottest, longest-lived fumaroles occurred in the upper VTTS near the 1912 vent where the ash-flow sheet is thicker, more indurated, and on average more mafic (richer in dacite and andesite) in contrast to the thinner, nonwelded rhyolitic tuff in the distal part of the sheet. Fumarolic activity was less intense in the distal part of the tuff because of lower emplacement temperatures, more diffuse fumarole conduits in the nonwelded tuff, and the thinness of the ash-flow sheet. Chemical leaching of ash-flow tuff by hot rising fluids took place adjacent to fumarolic conduits in deep parts of the fumaroles. Deposition of incrustation minerals, the components of which were carried upward by fumarolic gases, took place in the upper part of the ejecta, mostly in the fallout layers. The permeability difference between the ash-flow tuff and the overlying coarse dacite fallout was a critical factor in promoting the abrupt gradients in temperature, pressure, and fO2 that resulted in deposition of minerals from the fumarolic gases. The permeability difference between nonwelded ash-flow tuff and overlying fine-grained fall layers in the lower VTTS is less pronounced. The total mass of fumarolically deposited minerals appears large at first glance owing to the conspicuous coloration by Fe minerals; the mass is appreciably less than is apparent, however, because most incrustations are composed largely of ejecta coated or cemented by fine-grained fumarolic minerals. A large mass of unstable incrustation minerals, mainly chlorides and sulfates, reported during the 1917-1919 studies have since been removed by dissolution and weathering. In the vent region, argillic alteration that followed high-temperature degassing is localized along arcuate subsidence fractures in fallback ejecta. At widely scattered residual orifices, fumarolic gases presently are near-neutral steam, and temperatures are as hot as 90-degrees-C. RP KEITH, TEC (reprint author), US GEOL SURVEY,MENLO PK,CA 94025, USA. NR 32 TC 37 Z9 37 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD APR PY 1991 VL 45 IS 3-4 BP 227 EP 254 DI 10.1016/0377-0273(91)90061-4 PG 28 WC Geosciences, Multidisciplinary SC Geology GA FM464 UT WOS:A1991FM46400006 ER PT J AU BERRY, CR BABEY, GJ SHRADER, T AF BERRY, CR BABEY, GJ SHRADER, T TI EFFECT OF LERNAEA-CYPRINACEA (CRUSTACEA, COPEPODA) ON STOCKED RAINBOW-TROUT (ONCORHYNCHUS-MYKISS) SO JOURNAL OF WILDLIFE DISEASES LA English DT Article DE ANCHORWORM; LERNAEA-CYPRINACEA; RAINBOW TROUT; HISTOPATHOLOGY; PARASITE; RECREATIONAL FISHING; ONCORHYNCHUS-MYKISS; COPEPODA ID FISH AB Prevalence, intensity and pathogenesis of Lernaea cyprinacea (anchorworm) in stocked rainbow trout (Oncorhynchus mykiss) fingerlings were monitored annually for 4 yr (1981 to 1984) in East Canyon Reservoir, Utah (USA). Anchorworms were first detected in midsummer each year and were most abundant in the fall. The mean parasite intensity was highest in October 1982 (19 anchorworms per fish); in other years, maximum density was 7 to 9. The dorsal and caudal areas of the fish were the most heavily parasitized. The histological response to parasite attachment included an infectious granuloma similar to that reported in other fish hosts. Bacteria were not found in the kidneys of fish before stocking, but afterward bacteria that were presumptively identified as belonging to the genus Aeromonas, were found in the kidneys of up to 45% of the parasitized fish. Most (94%) anglers noticed the anchorworms, but few (8%) discarded parasitized fish. Some 28% used special cleaning techniques to prepare fish but 49% did nothing special to clean them. Lernaeosis probably had little effect on the fishery management goals for the reservoir. C1 UTAH STATE UNIV,US FISH & WILDLIFE SERV,UTAH COOPERAT FISHERY RES UNIT,LOGAN,UT 84322. CONNECTICUT DEPT ENVIRONM PROTECT,BUR FISHERIES,HARTFORD,CT 06106. OREGON DEPT FISH & WILDLIFE,BEND,OR 97702. RP BERRY, CR (reprint author), S DAKOTA STATE UNIV,S DAKOTA COOPERAT FISH & WILDLIFE RES UNIT,BROOKINGS,SD 57007, USA. NR 36 TC 12 Z9 15 U1 0 U2 2 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD APR PY 1991 VL 27 IS 2 BP 206 EP 213 PG 8 WC Veterinary Sciences SC Veterinary Sciences GA FJ644 UT WOS:A1991FJ64400002 PM 2067042 ER PT J AU KHAN, MA GOYAL, SM DIESCH, SL MECH, LD FRITTS, SH AF KHAN, MA GOYAL, SM DIESCH, SL MECH, LD FRITTS, SH TI SEROEPIDEMIOLOGY OF LEPTOSPIROSIS IN MINNESOTA WOLVES SO JOURNAL OF WILDLIFE DISEASES LA English DT Article DE LEPTOSPIROSIS; LEPTOSPIRA-INTERROGANS; SEROVARS; WOLVES; CANIS-LUPUS; SEROEPIDEMIOLOGY; ZOONOSIS; SURVEY ID CANINE PARVOVIRUS; ANTIBODIES; INFECTION AB Serum samples (n = 457) from wolves (Canis lupus) in northern Minnesota were collected from 1972 through 1986 and were tested for antibodies against Leptospira interrogans using a microtiter agglutination test. Twelve serovars included in the study were: australis, autumnalis, ballum, bataviae, bratislava, canicola, copenhageni, grippotyphosa, hardjo, pomona, pyrogenes, and tarassovi. Fifty-two (11%) sera had antibody titers of greater-than-or-equal-to 1:50 against one or more serovars of L. interrogans. The seroprevalence of different serovars in decreasing order was: grippotyphosa, bratislava, autumnalis, canicola, pomona, ballum, pyrogenes, hardjo, and copenhageni. No antibodies were found against australis, bataviae, and tarassovi. These results indicate that L. interrogans infection may occur in wolves of Minnesota. C1 US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. RP KHAN, MA (reprint author), UNIV MICHIGAN,COLL VET MED,DEPT VET DIAGNOST INVESTIGAT,ANN ARBOR,MI 48108, USA. NR 34 TC 14 Z9 15 U1 1 U2 1 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD APR PY 1991 VL 27 IS 2 BP 248 EP 253 PG 6 WC Veterinary Sciences SC Veterinary Sciences GA FJ644 UT WOS:A1991FJ64400008 PM 2067045 ER PT J AU FLICKINGER, EL JUENGER, G ROFFE, TJ SMITH, MR IRWIN, RJ AF FLICKINGER, EL JUENGER, G ROFFE, TJ SMITH, MR IRWIN, RJ TI POISONING OF CANADA GEESE IN TEXAS BY PARATHION SPRAYED FOR CONTROL OF RUSSIAN WHEAT APHID SO JOURNAL OF WILDLIFE DISEASES LA English DT Article DE ANTICHOLINESTERASE POISONING; BRAIN CHOLINESTERASE ACTIVITY; BRANTA-CANADENSIS; CANADA GEESE; MORTALITY; ORGANOPHOSPHORUS INSECTICIDE; PARATHION; PLAYA LAKES; RUSSIAN WHEAT APHID ID ORGANO-PHOSPHORUS INSECTICIDES AB Approximately 200 Canada geese (Branta canadensis) died at a playa lake in the Texas Panhandle shortly after a winter wheat field in the basin adjacent to the lake was treated with parathion to control newly invading Russian wheat aphids (Diuraphis noxia). No evidence of infectious disease was diagnosed during necropsies of geese. Brain ChE activities were depressed up to 77% below normal. Parathion residues in GI tract contents of geese ranged from 4 to 34 ppm. Based on this evidence, parathion was responsible for the goose mortalities. Parathion applications to winter wheat will undoubtedly increase if parathion is applied for control of both Russian wheat aphids and greenbugs (Schizaphis graminum). Geese may potentially be exposed to widespread applications of parathion from fall to spring, essentially their entire wintering period. C1 US FISH & WILDLIFE SERV,BUFFALO LAKE NAT WILDLIFE REFUGE,UMBARGER,TX 79091. US FISH & WILDLIFE SERV,NATL WILDLIFE HLTH RES CTR,MADISON,WI 53711. US FISH & WILDLIFE SERV,ECOL SERV FIELD OFF,ARLINGTON,TX 76010. RP FLICKINGER, EL (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,GULF COAST RES STN,POB 2506,VICTORIA,TX 77902, USA. NR 11 TC 21 Z9 22 U1 0 U2 0 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD APR PY 1991 VL 27 IS 2 BP 265 EP 268 PG 4 WC Veterinary Sciences SC Veterinary Sciences GA FJ644 UT WOS:A1991FJ64400011 PM 2067047 ER PT J AU ROCKE, TE SAMUEL, MD AF ROCKE, TE SAMUEL, MD TI BRAIN ACETYLCHOLINESTERASE ACTIVITY IN BOTULISM-INTOXICATED MALLARDS SO JOURNAL OF WILDLIFE DISEASES LA English DT Note DE TYPE-C AVIAN BOTULISM; CHOLINESTERASE INHIBITION; ORGANOPHOSPHORUS AND CARBAMATE PESTICIDES; MALLARDS; ANAS-PLATYRHYN; CHOS AB Brain acetylcholinesterase (AChE) activity in captive-reared mallards (Anas platyrhynchos) that died of botulism was compared with euthanized controls. AChE levels for both groups were within the range reported for normal mallards, and there was no significant difference in mean AChE activity between birds that ingested botulism toxin and died and those that did not. RP ROCKE, TE (reprint author), US FISH & WILDLIFE SERV,NATL WILDLIFE HLTH RES CTR,6006 SCHROEDER RD,MADISON,WI 53711, USA. OI Rocke, Tonie/0000-0003-3933-1563 NR 15 TC 2 Z9 2 U1 0 U2 1 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD APR PY 1991 VL 27 IS 2 BP 317 EP 319 PG 3 WC Veterinary Sciences SC Veterinary Sciences GA FJ644 UT WOS:A1991FJ64400017 PM 2067053 ER PT J AU GESE, EM SCHULTZ, RD RONGSTAD, OJ ANDERSEN, DE AF GESE, EM SCHULTZ, RD RONGSTAD, OJ ANDERSEN, DE TI PREVALENCE OF ANTIBODIES AGAINST CANINE PARVOVIRUS AND CANINE-DISTEMPER VIRUS IN WILD COYOTES IN SOUTHEASTERN COLORADO SO JOURNAL OF WILDLIFE DISEASES LA English DT Note DE CANINE DISTEMPER VIRUS; CANINE PARVOVIRUS; CANIS-LATRANS; COYOTES; SEROPREVALENCE; SURVEY ID ENTERITIS; MINNESOTA; WOLVES AB Serum from 72 wild coyotes (Canis latrans) in southeastern Colorado (USA) was collected and analyzed for prevalence of antibody to canine parvovirus (CPV) and canine distemper virus (CDV) from 1985 to 1988. The prevalence of antibodies to CPV and CDV was 71% and 57%, respectively, for the 4 yr of the study. Prevalence of antibody to CPV did not differ among years, between sexes, or with age. Prevalence of antibody to CDV did not differ among years or between sexes, but was significantly higher in adults (62%) than juveniles (33%). Prevalence of antibodies against CPV and CDV in southeastern Colorado was comparable to results reported in other serologic surveys in the western United States. C1 US FISH & WILDLIFE SERV,COLORADO FISH & WILDLIFE ASSISTANCE OFF,GOLDEN,CO 80401. UNIV WISCONSIN,SCH VET MED,DEPT PATHOBIOL SCI,MADISON,WI 53706. RP GESE, EM (reprint author), UNIV WISCONSIN,DEPT WILDLIFE ECOL,MADISON,WI 53706, USA. RI Gese, Eric/B-4578-2011 NR 17 TC 21 Z9 21 U1 0 U2 3 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD APR PY 1991 VL 27 IS 2 BP 320 EP 323 PG 4 WC Veterinary Sciences SC Veterinary Sciences GA FJ644 UT WOS:A1991FJ64400018 PM 1648628 ER PT J AU STRONG, LL GILMER, DS BRASS, JA AF STRONG, LL GILMER, DS BRASS, JA TI INVENTORY OF WINTERING GEESE WITH A MULTISPECTRAL SCANNER SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID SPECTRAL RESPONSE; REFLECTANCE; WHEAT AB We used a multispectral scanner with an instantaneous-field-of-view (IFOV) that was larger than a goose to inventory winter concentrations of lesser snow geese (Chen caerulescens) on a water background. A simple linear mixture model of the image-forming process was inverted to estimate the proportion of the IFOV covered by geese. The mixture model prediction of the number of geese was 2% less than a manual count of geese on aerial photographs acquired simultaneously. We suggest that it is possible to inventory white geese and dark geese in mixed concentrations on water from visible and shortwave infrared reflectance measurements. Shortwave infrared (1,420-2,440 nm) reflectance measurements may be used to discriminate among dark species of geese. C1 TGS TECHNOL INC,NASA AMES RES CTR,MOFFETT FIELD,CA 94035. US FISH & WILDLIFE SERV,NO PRAIRIE WILDLIFE RES CTR,DIXON,CA 95620. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NR 28 TC 9 Z9 10 U1 0 U2 1 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD APR PY 1991 VL 55 IS 2 BP 250 EP 259 DI 10.2307/3809147 PG 10 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA FL596 UT WOS:A1991FL59600007 ER PT J AU BARKER, RJ HINES, JE NICHOLS, JD AF BARKER, RJ HINES, JE NICHOLS, JD TI EFFECT OF HUNTING ON ANNUAL SURVIVAL OF GRAY DUCKS IN NEW-ZEALAND SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article ID MALLARDS; RATES; MORTALITY AB We used band recovery data from grey ducks (Anas superciliosa) banded in New Zealand between 1957 and 1974 to test 2 null hypotheses: (1) hunting mortality is completely additive to natural sources of mortality, and (2) hunting mortality is completely compensated by changes in natural mortality. We modeled annual survival as a function of survival in the absence of hunting and the probability of death from hunting. The complete compensation hypothesis was rejected, but we were unable to reject the completely additive hypothesis. There was no evidence of sex- or age-specificity for the relationship between kill rate and annual survival rate. We used simulated data to evaluate model performance. Parameter estimates were unbiased despite the inclusion of estimates that lay outside the bounds of the parameter space, although model-based variance estimates were consistently less than empirical variances. Our results imply that harvest restrictions may be useful in effecting change in annual survival rates of grey ducks. C1 US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. RP BARKER, RJ (reprint author), UNIV FLORIDA,COOPERAT FISH & WILDLIFE RES UNIT,GAINESVILLE,FL 32611, USA. NR 16 TC 15 Z9 15 U1 1 U2 3 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD APR PY 1991 VL 55 IS 2 BP 260 EP 265 DI 10.2307/3809148 PG 6 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA FL596 UT WOS:A1991FL59600008 ER PT J AU SAUER, JR BORTNER, JB AF SAUER, JR BORTNER, JB TI POPULATION TRENDS FROM THE AMERICAN WOODCOCK SINGING-GROUND SURVEY, 1970-88 SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article AB Population trend analysis of American woodcock (Scolopax minor) using data from a singing-ground survey indicates population declines throughout the breeding range of the species between 1970 and 1988. In the eastern United States and Canada, this decline has been quite consistent throughout the period, but in the central portion of the continent the population increased during the 1970's and declined during the early 1980's. Observers differ in their ability to hear woodcock, and we document observer differences in the singing-grond survey data and incorporate them into our analyses. Habitat changes have been suggested as the most likely cause of declines in woodcock populations. C1 US FISH & WILDLIFE SERV,OFF MIGRATORY BIRD MANAGEMENT,LAUREL,MD 20708. RP SAUER, JR (reprint author), US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708, USA. NR 27 TC 15 Z9 16 U1 0 U2 2 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD APR PY 1991 VL 55 IS 2 BP 300 EP 312 DI 10.2307/3809154 PG 13 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA FL596 UT WOS:A1991FL59600014 ER PT J AU RIPPLE, WJ JOHNSON, DH HERSHEY, KT MESLOW, EC AF RIPPLE, WJ JOHNSON, DH HERSHEY, KT MESLOW, EC TI OLD-GROWTH AND MATURE FORESTS NEAR SPOTTED OWL NESTS IN WESTERN OREGON SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article AB We investigated how the amount of old-growth and mature forest influences the selection of nest sites by northern spotted owls (Strix occidentalis caurina) in the Central Cascade Mountains of Oregon. We used 7 different plot sizes to compare the proportion of mature and old-growth forest between 30 nest sites and 30 random sites. The proportion of old-growth and mature forest was significantly greater at nest sites than at random sites for all plot sizes (P less-than-or-equal-to 0.01). Thus, management of the spotted owl might require setting the percentage of old-growth and mature forest retained from harvesting at least 1 standard deviation above the mean for the 30 nest sites we examined. C1 OREGON STATE UNIV,COOPERAT WILDLIFE RES UNIT,CORVALLIS,OR 97331. OREGON STATE UNIV,US FISH & WILDLIFE SERV,COOPERAT WILDLIFE RES UNIT,CORVALLIS,OR 97331. RP RIPPLE, WJ (reprint author), OREGON STATE UNIV,DEPT FOREST RESOURCES,ENVIRONM REMOTE SENSING APPL,CORVALLIS,OR 97331, USA. NR 12 TC 36 Z9 37 U1 0 U2 6 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD APR PY 1991 VL 55 IS 2 BP 316 EP 318 DI 10.2307/3809156 PG 3 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA FL596 UT WOS:A1991FL59600016 ER PT J AU LINDSEY, GD ARENDT, WJ KALINA, J PENDLETON, GW AF LINDSEY, GD ARENDT, WJ KALINA, J PENDLETON, GW TI HOME RANGE AND MOVEMENTS OF JUVENILE PUERTO-RICAN PARROTS SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article AB We studied home range and movements of 15 radio-marked, juvenile Puerto Rican parrots (Amazona vittata) fledging from wild nests during summer and fall, 1985-87. When juvenile parrots remained in the nest valley, home ranges during 1986 (xBAR = 32 +/- 10 [SE] ha, n = 4) were larger (P = 0.0079) than during 1987 (xBAR = 13 +/- 6 ha, n = 5). After radio-marked parrots integrated into adult flocks, home ranges during 1986 (xBAR = 1,075 +/- 135 ha, n = 3) were similar (P = 0.10) to 1987 (xBAR = 416 +/- 62 ha, n = 2). Juvenile parrots restricted their movements to nest valleys an average of 58 +/- 29 days following fledging. After joining adult flocks, juvenile parrots routinely flew between the east and west slopes of the Luquillo Mountains but did not exhibit a seasonal pattern of movement. We recommend that captive-raised, juvenile parrots used in release programs be greater-than-or-equal-to 5 months old to ensure they are mature enough to integrate into wild flocks. C1 US FISH & WILDLIFE SERV,PATUXENT WILDLIFE RES CTR,LAUREL,MD 20708. US FOREST SERV,SO FOREST EXPT STN,INST TROP FORESTRY,RIO PIEDRAS,PR 00928. NR 13 TC 18 Z9 18 U1 0 U2 4 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD APR PY 1991 VL 55 IS 2 BP 318 EP 322 DI 10.2307/3809157 PG 5 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA FL596 UT WOS:A1991FL59600017 ER PT J AU COOPER, JAG FLORES, RM AF COOPER, JAG FLORES, RM TI SHORELINE DEPOSITS AND DIAGENESIS RESULTING FROM 2 LATE PLEISTOCENE HIGHSTANDS NEAR +5 AND +6 METERS, DURBAN, SOUTH-AFRICA SO MARINE GEOLOGY LA English DT Article ID CAPE-PROVINCE; SEA-LEVEL; RECONSTRUCTION; LIMESTONES; NEARSHORE; RIPPLES; FACIES; WALES; COAST; BAY AB In exposures of Pleistocene rocks on the east coast of South Africa, eight sedimentary facies were distinguished on the basis of petrology, grain size, internal structures and field relationships. These are interpreted as deposits of surf zone, breaker zone, swash zone, backbeach, boulder beach and dune environments. Three phases of deposition and diagenesis are recognized. As a result of the stabilising effect of pre-existing coastal facies, the deposits from successive sea level stands are stacked vertically in a narrow coast-normal strip. Early cementation prevented erosion of the deposits during subsequent transgressions. Deposition of subsequent facies took place on an existing coastal dune (Facies 1). A terrace was cut into this dune at a sea level 4.5 to 5 m above present. At this sea level, clastic shoreline sediments were deposited which make up the main sedimentary sequence exposed (Facies 2-7). The steep swash zone, coarse grain size, and comparison with modern conditions in the study area indicate clastic deposition on a high-energy, wave-dominated, microtidal coastline. Vertical stacking of progressively shallower water facies indicates progradation associated with slightly regressive conditions, prior to stranding of the succession above sea level. During a subsequent transgression to 5.5 or 6 m above present sea level, a second terrace was cut across the existing facies, which by then were partly lithified. A boulder beach (Facies 8) deposited on this terrace is indicative of high wave energy and a rocky coastline, formed by existing cemented coastal facies. Comparison with dated deposits from other parts of the South African coast suggest a Late Pleistocene age for Facies 2-8. Deposition was terminated by subsequent regression and continuing low sea levels during the remainder of the Pleistocene. Cementation of the facies took place almost entirely by carbonate precipitation. The presence of isopachous fibrous cements suggests early cementation of Facies 1, 2, 3 and 4 under marine conditions, initially as aragonite which has since inverted to calcite. Facies 5, 6 and 7 are cemented only by equant calcite spar, evidence of cementation in the meteoric phreatic and vadose zones. Lowering of the water table during regression caused the remaining pore space in Facies 1, 2, 3 and 4 to be filled with equant calcite spar. Decementation in a 130 cm wide zone is attributed to water table shifts associated with the later transgression which deposited Facies 8. The vertical stacking of the two depositional sequences may be attributed to rapid cementation of Facies 2, 3, 4, 5, 6 and 7 under humid, subtropical conditions. This lithified sequence then acted as a focus for deposition of coarse-grained shoreline facies (Facies 8) during the subsequent transgression. C1 US GEOL SURVEY,DENVER FED CTR,COAL GEOL BRANCH,DENVER,CO 80225. RP COOPER, JAG (reprint author), CSIR,DIV WATER TECHNOL,ESTUARINE & FRESHWATER POLLUT PROGRAMME,POB 17001,CONGELLA 4013,SOUTH AFRICA. OI Cooper, Andrew/0000-0003-4972-8812 NR 82 TC 20 Z9 21 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0025-3227 J9 MAR GEOL JI Mar. Geol. PD APR PY 1991 VL 97 IS 3-4 BP 325 EP 343 DI 10.1016/0025-3227(91)90124-M PG 19 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA FM070 UT WOS:A1991FM07000007 ER PT J AU OSHEA, TJ RATHBUN, GB BONDE, RK BUERGELT, CD ODELL, DK AF OSHEA, TJ RATHBUN, GB BONDE, RK BUERGELT, CD ODELL, DK TI AN EPIZOOTIC OF FLORIDA MANATEES ASSOCIATED WITH A DINOFLAGELLATE BLOOM SO MARINE MAMMAL SCIENCE LA English DT Article DE FLORIDA MANATEE; TRICHECHUS-MANATUS; RED TIDE; GYMNODINIUM-BREVE; DINOFLAGELLATES; BREVETOXINS; MORTALITY ID PTYCHODISCUS-BREVIS; TOXINS AB Over a 10-wk period in early 1982, 39 Florida manatees (Trichechus manatus latirostris) were found dead in the lower Caloosahatchee River and nearby waters of southwestern Florida. Two were killed by boats. The remainder showed no evidence of trauma. Lesions indicative of infectious agents were not identified, and bacteriological and contaminant residue findings were unremarkable. Non-specific lesions of congestion and hemorrhage were identified in brain tissue. Numerous reports were also received of manatee morbidity. Some distressed manatees showed no biochemical lesions in clinical analyses of blood samples and recovered quickly. Timing of manatee illness coincided with fish and double-crested cormorant (Phalacrocorax auritus) mortality and morbidity. A widespread bloom of the dinoflagellate red tide organism (Gymnodinium breve) also coincided with these incidents. G. breve produces potent neurotoxins (breve-toxins). Circumstantial evidence links these events, and possible routes of exposure may include ingestion of filter-feeding ascidians. Ecological conditions that magnified the extent of the epizootic included an early dispersal of manatees into the area from a nearby winter aggregation site and unusually high salinities that facilitated the inshore spread of the red tide bloom. Management responses to future episodes of red tide in manatee areas are suggested. C1 UNIV FLORIDA,J HILLIS MILLER HLTH CTR,COLL VET MED,DEPT COMPARAT & EXPTL PATHOL,GAINESVILLE,FL 32610. SEA WORLD FLORIDA,ORLANDO,FL 32821. RP OSHEA, TJ (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,SIRENIA PROJECT,412 NE 16TH AVE,GAINESVILLE,FL 32601, USA. OI Bonde, Robert/0000-0001-9179-4376 NR 31 TC 73 Z9 75 U1 5 U2 25 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD APR PY 1991 VL 7 IS 2 BP 165 EP 179 DI 10.1111/j.1748-7692.1991.tb00563.x PG 15 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA FK356 UT WOS:A1991FK35600006 ER PT J AU REID, JP RATHBUN, GB WILCOX, JR AF REID, JP RATHBUN, GB WILCOX, JR TI DISTRIBUTION PATTERNS OF INDIVIDUALLY IDENTIFIABLE WEST-INDIAN MANATEES (TRICHECHUS-MANATUS) IN FLORIDA SO MARINE MAMMAL SCIENCE LA English DT Article DE MANATEE; TRICHECHUS-MANATUS; PHOTOIDENTIFICATION; SCARS; DISTRIBUTION; MIGRATION; MOVEMENTS; AGGREGATIONS; FLORIDA ID ABUNDANCE AB Photographs of distinctively scarred manatees (Trichechus manatus) were taken at aggregation sites throughout Florida and assembled into a catalog for identifying individuals. Resightings of known manatees in different years or at different locations enabled us to document site fidelity and long-distance movements. Of the 891 individuals included in the catalog as of August 1986, 470 (53%) were resighted at least once. We documented 219 cases of seasonal returns to specific aggregation sites and 98 instances of movements between areas. Movements in excess of 820 km were documented for individuals on the east coast of Florida. Rapid movements south during early winter, as well as northerly spring movements, verify a seasonal migration pattern for many individuals along Florida's east coast. The wide-ranging migratory habits of manatees in Florida must be considered if meaningful management strategies are to be developed and implemented. C1 FLORIDA POWER & LIGHT CO,JUNO BEACH,FL 33408. RP REID, JP (reprint author), US FISH & WILDLIFE SERV,NATL ECOL RES CTR,SIRENIA PROJECT,412 NE 16TH AVE,GAINESVILLE,FL 32601, USA. OI Reid, James/0000-0002-8497-1132 NR 30 TC 38 Z9 41 U1 0 U2 18 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD APR PY 1991 VL 7 IS 2 BP 180 EP 190 DI 10.1111/j.1748-7692.1991.tb00564.x PG 11 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA FK356 UT WOS:A1991FK35600007 ER PT J AU Dowsett, HJ AF Dowsett, H. J. TI THE DEVELOPMENT OF A LONG-RANGE FORAMINIFER TRANSFER FUNCTION AND APPLICATION TO LATE PLEISTOCENE NORTH ATLANTIC CLIMATIC EXTREMES SO PALEOCEANOGRAPHY LA English DT Article AB North Atlantic transfer function GSF18 was developed from simplified core top planktic foraminifer census data. Simplifications are based upon similar environmental responses of some modern taxa and assumptions about the paleoecology of now extinct Pliocene taxa. GSF18 is evaluated through application to "time slice" data sets from the last glacial maximum (18 ka) and last interglacial (122 ka) of the North Atlantic Ocean. Quantitative sea-surface temperature estimates from GSF18 at 106 glacial sites and 18 interglacial sites are approximately equivalent to Climate: Long Range Investigation, Mapping, and Prediction (CLIMAP) results at the same sites: a glacial North Atlantic considerably cooler than modern conditions and a last interglacial North Atlantic approximately the same as or slightly warmer than modern conditions. Minor differences are explained by the taxonomic structure of GSF18 and provide further insight into the environmental and temporal robustness of the transfer function. C1 US Geol Survey, Reston, VA 22092 USA. RP Dowsett, HJ (reprint author), US Geol Survey, 970 Natl Ctr, Reston, VA 22092 USA. OI Dowsett, Harry/0000-0003-1983-7524 NR 29 TC 33 Z9 33 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0883-8305 J9 PALEOCEANOGRAPHY JI Paleoceanography PD APR PY 1991 VL 6 IS 2 BP 259 EP 273 DI 10.1029/90PA02541 PG 15 WC Geosciences, Multidisciplinary; Oceanography; Paleontology SC Geology; Oceanography; Paleontology GA V23JT UT WOS:000208339800005 ER PT J AU DWYER, WP COLT, J OWSLEY, DE AF DWYER, WP COLT, J OWSLEY, DE TI EFFECTIVENESS OF INJECTING PURE OXYGEN INTO SEALED COLUMNS FOR IMPROVING WATER-QUALITY IN AQUACULTURE SO PROGRESSIVE FISH-CULTURIST LA English DT Article AB Sealed columns are simple, effective devices for economically adding oxygen to water and have considerable potential for use in aquaculture. Increasing the oxygen content of water enables fish culturists to increase fish loads and improve the rearing environment. We conducted tests to evaluate the effectiveness of pure oxygen injected into sealed columns to increase dissolved oxygen (DO) levels in waters at four hatcheries. Nominal water flows of 770, 481, 385, and 288 gal/min were evaluated at gas-to-liquid ratios of 0.5, 1.0, 2.0, 3.0, and 4.0%. Delta DO (amount of oxygen added to the water) ranged from 6 to 28 ppm as gas-to-liquid ratios increased from 0.5 to 5.3. Tests also indicated that there were no differences in performance of a column with 3 ft of packing versus 5 ft of packing at the flows tested. Two types of packing were compared, but little difference between them was observed. Operation of one column with packing and one equipped with a spray nozzle without packing yielded similar results; the column with the nozzle performed as well as the column with packing at the higher water flows. C1 JAMES M MONTGOMERY CONSULTING ENGINEERS,BELLEVUE,WA 98005. US FISH & WILDLIFE SERV,DWORSHAK NATL FISH HATCHERY,OROFINO,ID 83520. RP DWYER, WP (reprint author), US FISH & WILDLIFE SERV,4050 BRIDGER CANYON RD,BOZEMAN,MT 59715, USA. NR 7 TC 4 Z9 4 U1 1 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 72 EP 80 DI 10.1577/1548-8640(1991)053<0072:EOIPOI>2.3.CO;2 PG 9 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800002 ER PT J AU EDSALL, DA SMITH, CE AF EDSALL, DA SMITH, CE TI EFFECT OF OXYGEN SUPERSATURATION ON RAINBOW-TROUT FED WITH DEMAND FEEDERS SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID SALMO-GAIRDNERI AB The influence of rearing rainbow trout (Oncorhynchus mykiss) in water with and without supplemental oxygen on growth, feed conversion, packed red blood cell volume (hematocrit), and survival was determined during a 100-d test with fish fed by self-actuated or demand feeders. Although the rainbow trout reared in oxygen-supplemented water (187% saturation) gained 34% more weight than those reared in control water (95% saturation), variability was high and the difference was not significant (P > 0.14). Supplemental oxygen had no effect on feed conversion and survival. The hematocrit was significantly reduced by supplemental oxygen, but only by 9%-still within the normal range for rainbow trout. RP EDSALL, DA (reprint author), US FISH & WILDLIFE SERV,CTR FISH TECHNOL,4050 BRIDGER CANYON RD,BOZEMAN,MT 59715, USA. NR 12 TC 8 Z9 8 U1 1 U2 3 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 95 EP 97 DI 10.1577/1548-8640(1991)053<0095:CEOOSO>2.3.CO;2 PG 3 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800006 ER PT J AU KINDSCHI, GA THOMPSON, RG MENDOZA, AP AF KINDSCHI, GA THOMPSON, RG MENDOZA, AP TI USE OF RACEWAY BAFFLES IN RAINBOW-TROUT CULTURE SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB Aluminum baffles were installed in two raceways and tested for use in a production situation. Rainbow trout (Oncorhynchus mykiss) of the Eagle Lake strain were reared for two studies (211 and 157 d) conducted in consecutive years. During the first study, we evaluated two raceways with baffles and two without. In baffled raceways, dorsal fin quality of the fish was improved and cleaning time was shortened. However, feed conversion was more efficient in control raceways without baffles. Weight gain, mortality, total length, and condition factor of fish and suspended solids in the effluent water did not differ between raceways types. During the second study, the baffled raceways were not equipped with a settling area; instead, baffles were added at the downstream end of the raceway, so solids were continually flushed. Among the variables monitored, only cleaning time was affected, because the baffled raceways were self-cleaning. Two major fish mortalities (1,101 and 4,442 fish) resulted from suffocation in baffled raceways over the 2-year study. We recommend that baffles not be used with wild strains of rainbow trout, or if they are, that precautions be taken during certain periods. C1 US FISH & WILDLIFE SERV,CRESTON NATL FISH HATCHERY,KALISPELL,MT 59901. RP KINDSCHI, GA (reprint author), US FISH & WILDLIFE SERV,BOZEMAN FISH TECHNOL CTR,4050 BRIDGER CANYON RD,BOZEMAN,MT 59715, USA. NR 8 TC 15 Z9 15 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 97 EP 101 DI 10.1577/1548-8640(1991)053<0097:UORBIR>2.3.CO;2 PG 5 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800007 ER PT J AU GILDERHUS, PA LEMM, CA WOODS, LC AF GILDERHUS, PA LEMM, CA WOODS, LC TI BENZOCAINE AS AN ANESTHETIC FOR STRIPED BASS SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB Benzocaine was tested as an anesthetic on juvenile and mature adult striped bass (Morone saxatilis). Concentrations of 55 mg/L at 22-degrees-C to 80 mg/L at 11-degrees-C effectively anesthetized fish in about 3 min. Recovery was more rapid as temperature increased. Fish survived concentrations of twice the effective concentration and exposure times up to 60 min at the effective concentration. Striped bass required higher concentrations for anesthetization than had been previously demonstrated for salmonid fishes, but safety margins for both concentration and exposure time were wider than for the salmonids. C1 US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR LEETOWN,KEARNEYSVILLE,WV 25430. BALTIMORE GAS & ELECT CO,CRANE AQUACULTURE FACIL,BALTIMORE,MD 21203. RP GILDERHUS, PA (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,LA CROSSE,WI 54602, USA. NR 5 TC 22 Z9 23 U1 1 U2 1 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 105 EP 107 DI 10.1577/1548-8640(1991)053<0105:BAAAFS>2.3.CO;2 PG 3 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800009 ER PT J AU POSTON, HA WILLIAMS, RC AF POSTON, HA WILLIAMS, RC TI INFLUENCE OF FEEDING RATE ON PERFORMANCE OF ATLANTIC SALMON FRY IN AN OZONATED WATER REUSE SYSTEM SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID DENSITY AB A 4-week trial was conducted to determine the optimal feeding level in percent body weight of a commercially prepared, practical diet for early feeding fry of Atlantic salmon (Salmo salar) in an ozonated water reuse system at 17-18-degrees-C. Triplicate groups of swim-up (0.19-g) fry were fed one of seven levels of Biodiet starter diet calculated for hatchery constants of 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, and 8.5. Feeding levels (percent body weight) were derived at the start of the study and again at 2 weeks by dividing mean body length, in inches, into the respective hatchery constant. Mean body weight and body fat content increased significantly with each increment in level of feeding through a hatchery constant of 6.5, after which there was no further increase. Body protein decreased as feeding increased through hatchery constant 6.5; ash content decreased through hatchery constant 5.5. Results indicated that young Atlantic salmon fed at low feeding rates (2.47-5.44% body weight) in the water reuse system were underfed, but fish fed at 5.46-8.41% body weight grew at a favourable rate. RP POSTON, HA (reprint author), US FISH & WILDLIFE SERV,TUNISON LAB FISH NUTR,3075 GRACIE RD,CORTLAND,NY 13045, USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 111 EP 113 DI 10.1577/1548-8640(1991)053<0111:IOFROP>2.3.CO;2 PG 3 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800011 ER PT J AU PARAUKA, FM TROXEL, WJ CHAPMAN, FA MCBAY, LG AF PARAUKA, FM TROXEL, WJ CHAPMAN, FA MCBAY, LG TI HORMONE-INDUCED OVULATION AND ARTIFICIAL SPAWNING OF GULF OF MEXICO STURGEON (ACIPENSER-OXYRHYNCHUS-DESOTOI) SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID TRANSMONTANUS RICHARDSON; WHITE STURGEON AB Successful hormone-induced ovulation and artificial spawning of Gulf of Mexico sturgeon from the Suwannee River, Florida, with pituitary extract of common carp (Cyprinus carpio) was accomplished at two sites during spring 1989. Eggs were surgically removed from two fish weighing approximately 68 kg each. Two males, 18.3 and 19.3 kg, were used to fertilize the eggs of one female, and three males, 25.1, 25.9, and 26.2 kg, were used to fertilize the eggs of the second. Eggs were hatched on site in vertical tray incubators and McDonald hatching jars. Approximately 5,000 1-d-old fry were produced from one female; however, the fry failed to accept an artificial diet, and all but two died within 3 weeks of hatching. Over 3,000 fry were produced from the second female, and 60 17-d-old fry were stocked in the Suwannee River, Florida. The remaining fry did not actively feed and died within 21 d of hatch. C1 UNIV CALIF DAVIS,DEPT ANIM SCI,DAVIS,CA 95616. US FISH & WILDLIFE SERV,ATLANTA,GA 30303. RP PARAUKA, FM (reprint author), US FISH & WILDLIFE SERV,1612 JUNE AVE,PANAMA CITY,FL 32405, USA. NR 14 TC 24 Z9 25 U1 2 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 113 EP 117 DI 10.1577/1548-8640(1991)053<0113:HIOAAS>2.3.CO;2 PG 5 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800012 ER PT J AU SODERBERG, RW MEADE, JW AF SODERBERG, RW MEADE, JW TI THE EFFECTS OF IONIC-STRENGTH ON UN-IONIZED AMMONIA CONCENTRATION SO PROGRESSIVE FISH-CULTURIST LA English DT Note ID WATER; PH AB Ionic strength affects the ionization of ammonia and the resulting un-ionized ammonia (NH3) concentration. The error introduced by failure to account for this effect can be substantial in marine or brackish water. We present a simple method for correcting the calculation of the NH3 fraction in an ammonia solution for ionic strength. C1 US FISH & WILDLIFE SERV,TUNISON LAB FISH NUTR,CORTLAND,NY 13045. RP SODERBERG, RW (reprint author), MANSFIELD UNIV,FISHERIES PROGRAM,MANSFIELD,PA 16933, USA. NR 13 TC 12 Z9 16 U1 2 U2 3 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 118 EP 120 DI 10.1577/1548-8640(1991)053<0118:TEOISO>2.3.CO;2 PG 3 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800013 ER PT J AU KINCAID, HL CALKINS, GT AF KINCAID, HL CALKINS, GT TI RAPID CLASSIFICATION OF NUCLEAR CATARACTS IN LAKE TROUT SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB To examine lake trout (Salvelinus namaycush) in the field for cataract and noncataract eye abnormalities, we developed a procedure with a circular 1.7-power illuminated magnifying lamp. A box in which the lamp is mounted facilitates its transport and provides a support base for the lamp during use in the field. A classification system was developed for assigning nuclear cataracts to four stages based on cataract size as a percentage of the total cross-sectional area of the lens. When the method was used by newly trained technicians to screen 200,000 fall lake trout fingerlings into cataract and noncataract groups, the error rates were 1.7 and 7.7%, respectively. A technician could examine up to 2,800 fingerlings, 1,300 yearlings, or 700 3-year-old fish per day. RP KINCAID, HL (reprint author), US FISH & WILDLIFE SERV,NATL FISHERY RES & DEV LAB,RURAL DELIVERY 4,BOX 63,WELLSBORO,PA 16901, USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 120 EP 124 DI 10.1577/1548-8640(1991)053<0120:RCONCI>2.3.CO;2 PG 5 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800014 ER PT J AU ROTTIERS, DV AF ROTTIERS, DV TI TOWABLE CAGE FOR STUDIES OF SMOLTIFICATION IN ATLANTIC SALMON SO PROGRESSIVE FISH-CULTURIST LA English DT Article AB The floating towable cage described in this report was used successfully to hold and transport Atlantic salmon (Salmo salar) in estuarine waters. These rugged and versatile cages, constructed from readily available, inexpensive materials, were tied singly and in clusters to floating docks in fresh and brackish water, where they withstood strong currents, winds, floods, and tides for 2.5 months without visible damage. RP ROTTIERS, DV (reprint author), US FISH & WILDLIFE SERV,NATL FISHERY RES & DEV LAB,RURAL DELIVERY 4,BOX 63,WELLSBORO,PA 16901, USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 124 EP 127 DI 10.1577/1548-8640(1991)053<0124:TCFSOS>2.3.CO;2 PG 4 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800015 ER PT J AU LUDWIG, GM TACKETT, DL AF LUDWIG, GM TACKETT, DL TI RELATION BETWEEN BAR GRADER SIZE AND SIZE OF STRIPED BASS SO PROGRESSIVE FISH-CULTURIST LA English DT Note AB Regression equations and a table that express the relation between bar grader spacing and total lengths and weights were determined for 5-7-month-old striped bass (Morone saxatilis). RP LUDWIG, GM (reprint author), US FISH & WILDLIFE SERV,FISH FARMING EXPTL LAB,STUTTGART,AR 72160, USA. NR 15 TC 2 Z9 2 U1 0 U2 1 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0033-0779 J9 PROG FISH CULT JI Progress. Fish-Cult. PD APR PY 1991 VL 53 IS 2 BP 128 EP 129 DI 10.1577/1548-8640(1991)053<0128:RBBGSA>2.3.CO;2 PG 2 WC Fisheries SC Fisheries GA GA878 UT WOS:A1991GA87800016 ER PT J AU SALTUS, RW LACHENBRUCH, AH AF SALTUS, RW LACHENBRUCH, AH TI THERMAL EVOLUTION OF THE SIERRA-NEVADA - TECTONIC IMPLICATIONS OF NEW HEAT-FLOW DATA SO TECTONICS LA English DT Article ID ISOSTATIC RESIDUAL GRAVITY; WESTERN UNITED-STATES; ROCKY MOUNTAINS; UPLIFT; CALIFORNIA; CRUSTAL; BASIN; GEOMETRY; VALLEY; RADIOACTIVITY AB Eight new heat flow measurements in the southern Sierra Nevada constrain models of thermal evolution and lithospheric structure. Low reduced heat flows (18 to 21 mW/m2) in the southwest Sierra Nevada are consistent with previous results from the northwestern and central Sierra Nevada and extend the known region of linear heat flow-heat production correlation an additional 150 km to the south. Isostatic residual gravity and measured rock densities are also linearly correlated in the central Sierra Nevada, suggesting a general association between the upper crustal distribution of density and heat production. The linear residual gravity-density relation implies that isostatic residual gravity anomalies have upper crustal sources and therefore is evidence against a flexural model of Cenozoic Sierra Nevada uplift. New reduced heat flows measured in the southeast Sierra Nevada are relatively high (32 to 57 mW/m2) and correlate spatially with a region of high seismicity that includes extensional earthquake swarms; this correlation supports the view that Basin and Range extensional tectonics and associated magmatic processes are encroaching on the eastern Sierra Nevada. In the stable southwest Sierra Nevada, as in the central and northwestern Sierra Nevada, the persistence of low reduced heat flow at the surface is consistent with a thermal origin for the Cenozoic uplift of the Sierra Nevada, provided the conductive lithosphere is at least 60 to 90 km thick. Simple order-of-magnitude calculations show that thermal uplift models combining mechanisms such as advective warming and thinning of the mantle lithosphere, advection of basaltic magma and heat into the crust, simple thermal expansion, and eclogite-to-basalt phase conversion can account for the timing and amount of Cenozoic Sierra Nevada uplift. Thermal models do not need the assumptions of unusual lithospheric strength and crustal buoyancy required by mechanical models for Cenozoic uplift driven by a Mesozoic crustal root. C1 STANFORD UNIV,DEPT GEOPHYS,STANFORD,CA 94305. RP SALTUS, RW (reprint author), US GEOL SURVEY,MAIL STOP 923,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 90 TC 62 Z9 62 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0278-7407 J9 TECTONICS JI Tectonics PD APR PY 1991 VL 10 IS 2 BP 325 EP 344 DI 10.1029/90TC02681 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA FD987 UT WOS:A1991FD98700007 ER PT J AU HELSEL, DR ANDREWS, ED AF HELSEL, DR ANDREWS, ED TI TRENDS IN FRESH-WATER INFLOW TO SAN-FRANCISCO BAY FROM THE SACRAMENTO-SAN-JOAQUIN DELTA - DISCUSSION SO WATER RESOURCES BULLETIN LA English DT Discussion C1 US DEPT INTERIOR,GEOL SURVEY,DENVER,CO 80225. RP HELSEL, DR (reprint author), US DEPT INTERIOR,GEOL SURVEY,RESTON,VA 22092, USA. NR 1 TC 2 Z9 2 U1 0 U2 1 PU AMER WATER RESOURCES ASSOC PI HERNDON PA 950 HERNDON PARKWAY SUITE 300, HERNDON, VA 22070-5528 SN 0043-1370 J9 WATER RESOUR BULL JI Water Resour. Bull. PD APR PY 1991 VL 27 IS 2 BP 317 EP 319 PG 3 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA GD212 UT WOS:A1991GD21200015 ER PT J AU HAY, LE MCCABE, GJ WOLOCK, DM AYERS, MA AF HAY, LE MCCABE, GJ WOLOCK, DM AYERS, MA TI SIMULATION OF PRECIPITATION BY WEATHER TYPE ANALYSIS SO WATER RESOURCES RESEARCH LA English DT Article AB A method of precipitation simulation that incorporates climatological information has been developed. A Markovian-based model is used to generate temporal sequences of six daily weather types: high pressure; coastal return; maritime tropical return; frontal maritime tropical return; cold frontal overrunning; and warm frontal overrunning. Precipitation values are assigned to individual days by using observed statistical relations between weather types and precipitation characteristics. When this method was applied to an area in the Delaware River basin, the statistics describing average precipitation, extreme precipitation, and drought conditions for simulated precipitation closely matched those of the observed data. Potential applications of this weather type precipitation model include climatic change research and modeling of temperature and evapotranspiration. C1 US GEOL SURVEY,DIV WATER RESOURCES,W TRENTON,NJ 08628. RP HAY, LE (reprint author), US GEOL SURVEY,DENVER FED CTR,DIV WATER RESOURCES,MAIL STOP 412,BOX 25046,DENVER,CO 80225, USA. NR 15 TC 108 Z9 108 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD APR PY 1991 VL 27 IS 4 BP 493 EP 501 DI 10.1029/90WR02650 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FF714 UT WOS:A1991FF71400005 ER PT J AU NIMMO, JR AF NIMMO, JR TI TREATMENT OF RESIDUAL WATER-CONTENT IN A CONSISTENT SET OF PARAMETRIC MODELS FOR THE 2-PHASE FLOW OF IMMISCIBLE FLUIDS IN THE SUBSURFACE - COMMENT SO WATER RESOURCES RESEARCH LA English DT Note ID HYDRAULIC CONDUCTIVITY RP NIMMO, JR (reprint author), US GEOL SURVEY,DIV WATER RESOURCES,345 MIDDLEFIELD RD,MAIL STOP 421,MENLO PK,CA 94025, USA. NR 7 TC 55 Z9 55 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD APR PY 1991 VL 27 IS 4 BP 661 EP 662 DI 10.1029/91WR00165 PG 2 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA FF714 UT WOS:A1991FF71400024 ER PT J AU MCGARIGAL, K ANTHONY, RG ISAACS, FB AF MCGARIGAL, K ANTHONY, RG ISAACS, FB TI INTERACTIONS OF HUMANS AND BALD EAGLES ON THE COLUMBIA RIVER ESTUARY SO WILDLIFE MONOGRAPHS LA English DT Article ID RESPONSES; RESIDUES; MERCURY; OREGON; AREAS; EGGS AB Human activities have had profound effects on bald eagle (Haliaeetus leucocephalus) populations. Few experimental studies exist that address the effects of human activities on foraging eagles during the breeding season. Information from these types of studies is needed so that resource managers can allow humans and eagles to coexist. We investigated the response of breeding bald eagles to human activities in foraging areas on the Columbia River estuary, Washington-Oregon, during spring and summer, 1985 and 1986. We distinguished between 2 forms of interaction. In the first, a moving human approached a stationary eagle and induced a disturbance. This type of interaction was rare on the Columbia River estuary and accounted for a minor proportion of an eagle's time-energy budget. Only 20% of all moving human activities observed during this study resulted in human-eagle encounters within 500 m, and < 6% of all encounters resulted in a visible disturbance to an eagle. In the second form of interaction, an eagle had a choice of alternative foraging sites, some of which may have had human activities occurring nearby. In this situation, the eagle had the freedom to choose a destination, given the pattern of human activities. This type of interaction represented the major form of human-eagle interaction on the Columbia River estuary. To investigate this, we studied 6 pairs of eagles in each of 2 years; each pair was sampled 3 times during the breeding season, corresponding to incubation, nestling, and postfledging stages of the nesting cycle. Each sample consisted of a 3-day control period, during which we monitored "normal" eagle activity patterns, and a 3-day influence period, during which we "disturbed" (i.e., stationary boat with observer) a high-use foraging area. We compared eagle activity patterns within 1,200 m of the experimental disturbance between sampling periods. Eagles typically avoided an area within 400 m of the experimental stationary boat, although avoidance areas ranged between 200-900 m among pairs. In most cases, eagles spent less time and made fewer foraging attempts in the sample area during the influence period. Responses were consistent among nesting stages, although foraging activity increased dramatically and was more concentrated in the high-use areas during the later nesting stages. Although we cannot decisively conclude that human activities were directly responsible for current eagle spatial use patterns, the results of the experimental disturbances confirmed that boating activities have the potential to significantly affect eagle spatial use patterns. Based on these results, we developed a model of human-eagle interactions in foraging areas. We used this model and the results of this study to develop several alternative management strategies involving temporal and spatial restrictions of human activity. We recommend buffer zones 400-800 m wide around high-use foraging areas of bald eagles as the most appropriate management strategy for the Columbia River estuary. C1 OREGON STATE UNIV,US FISH & WILDLIFE SERV,OREGON COOPERAT WILDLIFE RES UNIT,CORVALLIS,OR 97331. OREGON STATE UNIV,OREGON COOPERAT WILDLIFE RES UNIT,CORVALLIS,OR 97331. NR 72 TC 17 Z9 18 U1 1 U2 9 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0084-0173 J9 WILDLIFE MONOGR JI Wildl. Monogr. PD APR PY 1991 IS 115 BP 1 EP 47 PG 47 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA FL788 UT WOS:A1991FL78800001 ER PT J AU MEINERTZ, JR GINGERICH, WH ALLEN, JL AF MEINERTZ, JR GINGERICH, WH ALLEN, JL TI METABOLISM AND ELIMINATION OF BENZOCAINE BY RAINBOW-TROUT, ONCORHYNCHUS-MYKISS SO XENOBIOTICA LA English DT Article ID BENZOIC-ACID; FISH; EXCRETION; GILLS; KIDNEY AB 1. Branchial and urinary elimination of benzocaine residues was evaluated in adult rainbow trout, Oncorhynchus mykiss, given a single dorsal aortic dose of C-14-benzocaine hydrochloride. 2. Branchial elimination of benzocaine residues was rapid and accounted for 59.2% of the dose during the first 3 h after dosing. Renal elimination of radioactivity was considerably slower; the kidney excreted 2.7% dose within 3 h and 9.0% within 24 h. Gallbladder bile contained 2.0% dose 24 h after injection. 3. Of the radioactivity in radiochromatograms from water taken 3 min after injection, 87.3% was benzocaine and 12.7% was N-acetylated benzocaine. After 60 min, 32.7% was benzocaine and 67.3% was N-acetylated benzocaine. 4. Of the radioactivity in radiochromatograms from urine taken 1 h after dosing, 7.6% was para-aminobenzoic acid, 59.7% was N-acetylated para-aminobenzoic acid, 19.5% was benzocaine, and 8.0% was N-acetylated benzocaine. The proportion of the radioactivity in urine changed with time so that by 20 h, 1.0% was para-aminobenzoic acid and 96.6% was N-acetylated para-aminobenzoic acid. 5. Benzocaine and a more hydrophobic metabolite, N-acetylated benzocaine, were eliminated primarily through the gills; renal and biliary pathways were less significant elimination routes for benzocaine residues. C1 UNIV WISCONSIN,DEPT BIOL,LA CROSSE,WI 54601. US FISH & WILDLIFE SERV,NATL FISHERIES RES CTR,LA CROSSE,WI 54602. NR 27 TC 26 Z9 26 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0049-8254 J9 XENOBIOTICA JI Xenobiotica PD APR PY 1991 VL 21 IS 4 BP 525 EP 533 PG 9 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA FM060 UT WOS:A1991FM06000011 PM 1897251 ER PT J AU BRUCE, DS AMBLER, DL HENSCHEL, TM OELTGEN, PR NILEKANI, SP AMSTRUP, SC AF BRUCE, DS AMBLER, DL HENSCHEL, TM OELTGEN, PR NILEKANI, SP AMSTRUP, SC TI OPIOIDS AND HIBERNATION - PHYSIOLOGICAL-EFFECTS OF PLASMA-ALBUMIN FRACTIONS FROM 4 HIBERNATING SPECIES ON INDUCED CONTRACTILITY OF GUINEA-PIG ILEUM MYENTERIC PLEXUS-LONGITUDINAL MUSCLE STRIP SO FASEB JOURNAL LA English DT Meeting Abstract C1 US FISH & WILDLIFE SERV,ALASKA FISH & WILDLIFE RES CTR,ANCHORAGE,AK 99503. WHEATON COLL,DEPT BIOL,WHEATON,IL 60187. VET ADM MED CTR,LEXINGTON,KY 40511. UNIV KENTUCKY,COLL MED,DEPT PATHOL,LEXINGTON,KY 40506. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 11 PY 1991 VL 5 IS 4 BP A395 EP A395 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA FC207 UT WOS:A1991FC20700145 ER PT J AU CALDERONE, GJ BUTLER, RF AF CALDERONE, GJ BUTLER, RF TI THE EFFECTS OF NOISE DUE TO RANDOM UNDETECTED TILTS AND PALEOSECULAR VARIATION ON REGIONAL PALEOMAGNETIC DIRECTIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID INCLINATION DATA AB Random tilting of a single paleomagnetic vector produces a distribution of vectors which is not rotationally symmetric about the original vector and therefore not Fisherian. Monte Carlo simulations were performed on two types of vector distributions: (1) distributions of vectors formed by perturbing a single original vector with Fisher distribution of bedding poles (each defining a tilt correction) and (2) standard Fisher distributions. These simulations demonstrate that inclinations of vectors drawn from both distributions are biased toward shallow inclinations. There is a greater likelihood of statistically "drawing" a vector shallower than the true mean vector than of drawing one that is steeper. The estimated probability increases as a function of angular dispersion and inclination of the true mean vector. Consequently, the interpretation of inclination-only data from either type of distribution is not straightforward, especially when the expected paleolatitude is greater than about 50-degrees. Because of the symmetry of the two distributions, declinations of vectors in each distribution are unbiased. The Fisher mean direction of the distribution of vectors formed by perturbing a single vector with random undetected tilts is biased toward shallow inclinations. but this bias is insignificant for angular dispersions of bedding poles less than 20-degrees. This observation implies that the mean pole calculated from a large set of paleomagnetic directions obtained for coeval rocks over a region will be effectively unbiased by random undetected tilts of those rocks provided the angular dispersion of the undetected tilts is less than about 20-degrees. However, the bias of the mean can be significant for large (> 20-degrees) angular dispersion of tilts. The amount of bias of the mean direction maximizes at about 10-degrees-12-degrees in mid-latitude regions but is usually less than 8-degrees. Consequently, large (> 12-degrees) inclination discordances are probably not the result of random undetected tilts, even if the angular dispersion of the tilts exceeds 20-degrees. C1 UNIV ARIZONA,DEPT GEOSCI,TUCSON,AZ 85721. RP CALDERONE, GJ (reprint author), US GEOL SURVEY,WESTERN REG GEOL BRANCH,2255 N GEMINI DR,FLAGSTAFF,AZ 86001, USA. NR 15 TC 6 Z9 6 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 3973 EP 3977 DI 10.1029/90JB02457 PG 5 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300009 ER PT J AU HUDSON, MR GEISSMAN, JW AF HUDSON, MR GEISSMAN, JW TI PALEOMAGNETIC EVIDENCE FOR THE AGE AND EXTENT OF MIDDLE TERTIARY COUNTERCLOCKWISE ROTATION, DIXIE VALLEY REGION, WEST CENTRAL NEVADA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID EAST HUMBOLDT RANGE; PLATE-BOUNDARY ZONE; K-AR AGES; TECTONIC ROTATION; SOUTHWEST WASHINGTON; CRUSTAL ROTATIONS; SOUTHERN NEVADA; RUBY MOUNTAINS; BLOCK ROTATION; GREAT-BASIN AB Paleomagnetic data obtained from Oligocene to lower Miocene igneous rocks and middle Miocene basaltic rocks at fifteen localities from a region surrounding Dixie Valley in west central Nevada indicate that parts of the area experienced counterclockwise vertical-axis rotation, and these data provide constraints on the extent and timing of rotation. Counterclockwise vertical-axis rotation probably exceeding 30-degrees is indicated for Oligocene to lower Miocene rocks in the central part of the study area. Calculated rotations increase with increasing age of the Oligocene to lower Miocene rocks, indicating that vertical-axis rotation was concurrent with ash-flow deposition (about 23-33 Ma). Paleomagnetic data indicate that middle Miocene basaltic rocks (about 10-17 Ma) postdate significant counterclockwise vertical-axis rotation, although this interpretation is complicated because the rocks were erupted episodically in pulses that apparently were short lived with respect to geomagnetic secular variation. Counterclockwise rotation was related to a deformation event that predated development of the present basin and range physiography of the area. The total amount of crustal rotation in Tertiary time in the area is poorly known. Rotation estimates calculated from time-averaged mean directions that incorporate data from a broad range of the Oligocene to lower Miocene units probably underestimate total Tertiary rotation because the mean directions include data from units that postdate much of the rotation. For example, a rotation estimate for a composite sequence from the central part of the study area is -23-degrees +/- 15-degrees, whereas estimates from older and younger halves of the sequence are -37-degrees +/- 21-degrees and -11-degrees +/- 16-degrees, respectively. Paleomagnetic data indicate that Oligocene to lower Miocene rocks at some localities in the northern and southern parts of the study area (e.g., the Golconda Canyon locality) probably did not experience significant Tertiary counterclockwise rotation. Although the paleomagnetic data alone are insufficient to fully define the geographic area subjected to Tertiary counterclockwise rotation, the data suggest that a discrete subregion was affected rather than the entire Basin and Range province. C1 UNIV NEW MEXICO,DEPT GEOL,ALBUQUERQUE,NM 87131. RP HUDSON, MR (reprint author), US GEOL SURVEY,BOX 25046,MS 913,DENVER,CO 80225, USA. NR 73 TC 17 Z9 17 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 3979 EP 4006 DI 10.1029/90JB02424 PG 28 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300010 ER PT J AU FUIS, GS AMBOS, EL MOONEY, WD CHRISTENSEN, NI GEIST, E AF FUIS, GS AMBOS, EL MOONEY, WD CHRISTENSEN, NI GEIST, E TI CRUSTAL STRUCTURE OF ACCRETED TERRANES IN SOUTHERN ALASKA, CHUGACH MOUNTAINS AND COPPER RIVER BASIN, FROM SEISMIC REFRACTION RESULTS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID VELOCITY STRUCTURE; SYNTHETIC SEISMOGRAMS; TECTONIC EVOLUTION; OCEANIC-CRUST; GREAT VALLEY; ISLAND-ARC; WRANGELLIA; TRANSECT; CALIFORNIA; COMPLEX AB Seismic refraction data were collected along a 320-km-long "Transect" line in southern Alaska, crossing the Prince William, Chugach, Peninsular, and Wrangellia terranes, and along several shorter lines within individual terranes. Velocity structure in the upper crust (less than 9-km depth) differs among the four terranes. In contrast, layers in the middle crust (9- to 25-km depth) in some cases extend across projected terrane boundaries. The following observations can be made: (1) An intermediate-velocity layer (6.4 km/s) at 9-km depth extends across the deep projection of the suture between the Chugach and Peninsular terranes, suggesting that the northern Chugach and southern Peninsular terranes are detached and rest on a deeper terrane of unknown origin. (2) The top of a gently north dipping sequence of low- and high-velocity layers (5.7-7.8 km/s), more than 10 km thick, extends from near the surface in the southern Chugach terrane to more than 20-km depth beneath the southern Peninsular terrane. This sequence, truncated by the suture between the Prince William and Chugach terranes, is interpreted to be an underplated "terrane" made up of fragments of the Kula plate and its sedimentary overburden that were accreted during subduction in the late Mesozoic and/or early Tertiary, during or between times of accretion of the Prince William and Chugach terranes. (3) A thick crustal "root", with a laminated sequence at its top, extends from a depth of 19 km to as much as 57 km beneath the northern Peninsular and Wrangellia terranes. This root extends across the deep projection of the suture between the Peninsular and Wrangellia terranes, although resolution of this apparent crosscutting relationship is relatively poor. This root may represent tectonically or, possibly, magmatically emplaced rocks. The lower crust beneath the Prince William, Chugach, and southern Peninsular terranes includes a north dipping, 3- to 8-km-thick section of subducting oceanic crust. C1 US GEOL SURVEY, MS 977, 345 MIDDLEFIELD RD, MENLO PK, CA 94025 USA. PURDUE UNIV, DEPT EARTH & ATMOSPHER SCI, W LAFAYETTE, IN 47907 USA. RP CALIF STATE UNIV LONG BEACH, DEPT GEOL SCI, LONG BEACH, CA 90840 USA. OI Fuis, Gary/0000-0002-3078-1544 NR 80 TC 55 Z9 55 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 4187 EP 4227 DI 10.1029/90JB02316 PG 41 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300025 ER PT J AU FUIS, GS PLAFKER, G AF FUIS, GS PLAFKER, G TI EVOLUTION OF DEEP-STRUCTURE ALONG THE TRANS-ALASKA CRUSTAL TRANSECT, CHUGACH MOUNTAINS AND COPPER RIVER BASIN, SOUTHERN ALASKA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID METAMORPHIC COMPLEX; TECTONIC EVOLUTION; VANCOUVER-ISLAND; HEAT-FLOW; WRANGELLIA; TERRANES; PLATE; RANGE; SUBDUCTION; ZONE AB One of the most important results of the Trans-Alaska Crustal Transect investigations is the discovery that more than one third of the North American plate in southern Alaska (Chugach Mountains and Copper River basin) consists of tectonically underplated oceanic lithosphere. In southern Alaska, exposed accreted tectonostratigraphic terranes, include, from south to north along the transect, the Prince William, Chugach, Peninsular, and Wrangellia terranes. Chief results from seismic refraction data include the following: (1) A sequence of layers of low and high velocity (5.7-7.8 km/s), more than 10 km thick, dips gently northward, with its top at the surface in the southernmost Chugach terrane and at more than 20-km depth beneath the southern Peninsular terrane. A high-velocity layer at the top of this sequence corresponds to metabasalt in the southernmost Chugach terrane. This sequence is interpreted to be tectonically underplated fragments of the Kula plate and its sedimentary overburden. (2) An intermediate-velocity layer (6.35-6.5 km/s) at 9-km depth beneath both the northern Chugach and southern Peninsular terranes appears to extend without offset across the deep projection of the suture between these two terranes, the Border Ranges fault system. (3) A crustal "root" between depths of 19 and 57 km beneath the northern Peninsular and Wrangellia terranes appears to extend without offset across the deep projection of the suture between these two terranes, the West Fork fault system. This crustal root also appears to abut the tectonically underplated sequence to the south. Unfortunately, in results 2 and 3 the apparent crosscutting and abutting relationships can not be unambiguously resolved. Three scenarios, A, B, and C, have been offered to explain the evolution of this structure. Scenarios A and B differ in interpretation of the depth extent of the northern Chugach and southern Peninsular terranes. In scenario A these terranes extend to only 9-km depth, where they rest on an unknown middle crust, interpreted as a deeper part of the Peninsular terrane. In this scenario, the northern Chugach and southern Peninsular terranes moved landward as a tectonic wedge, during tectonic underplating in the latest Cretaceous or early Tertiary, and uplifted the upper crust of the Peninsular terrane to the north. In scenario B, the northern Chugach and southern Peninsular terranes extend to 20-km depth. In this scenario, they were compressed but not detached and displaced during accretion. Scenarios A, B, and C differ in interpretation of the deep crustal root that appears to abut the tectonically underplated sequence. Since the Peninsular and Wrangellia terranes were at or below sea level prior to the mid-Cretaceous, the root was probably emplaced in mid-Cretaceous or younger times. In scenario A the root is lower crust of North America that moved southward during tectonic underplating of the Kula plate. In scenario B the root is, in part, tectonically underplated rocks similar to the Kula plate sequence to the south. In scenario C the root is, in part, magmatically underplated rocks. RP FUIS, GS (reprint author), US GEOL SURVEY,MS 977,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. OI Fuis, Gary/0000-0002-3078-1544 NR 55 TC 30 Z9 30 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 4229 EP 4253 DI 10.1029/90JB02276 PG 25 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300026 ER PT J AU SAVAGE, JC PLAFKER, G AF SAVAGE, JC PLAFKER, G TI TIDE-GAUGE MEASUREMENTS OF UPLIFT ALONG THE SOUTH COAST OF ALASKA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID STRAIN ACCUMULATION; EARTHQUAKE; MODEL; DEFORMATION; RECORDS; JAPAN AB Annual mean sea levels along the south coast of Alaska are used to measure uplift along the Alaska-Aleutian subduction zone. Oceanographic effects are removed from the observed annual mean sea levels by subtracting a correction that is proportional to the sea level fluctuations observed in southeast Alaska. That correction is effective in reducing fluctuations in the observed, annual mean sea level as far west as the tip of Alaska peninsula. Additional corrections to remove the eustatic rise in sea level and the apparent fall in sea level due to postglacial isostatic rebound of the land are introduced. This corrected sea level record should provide a measure of tectonic subsidence. In the area affected by the 1964 Alaska earthquake, postseismic uplift occurs where coseismic subsidence was observed, and postseismic subsidence occurs where coseismic uplift was observed. The immediate postseismic response is damped out within the first decade, and the subsequent uplift rates appear to be steady over the 1974-1989 interval. However, some of those rates seem to be too high to be sustained over the approximately 1000 year earthquake recurrence interval appropriate to this area if the interseismic deformation is only to recover the coseismic displacement. Thus a long-term (approximately 100 years) relaxation in uplift rates is postulated. The immediate (time constant approximately 5 years) postseismic relaxation is attributed to postseismic slip on the plate interface directly downdip from the coseismic rupture. The long-term (time constant approximately 100 years) relaxation is attributed to flow in the asthenosphere. RP SAVAGE, JC (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MS 977,MENLO PK,CA 94025, USA. NR 26 TC 68 Z9 69 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 4325 EP 4335 DI 10.1029/90JB02540 PG 11 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300033 ER PT J AU COLLOT, JY FISHER, MA AF COLLOT, JY FISHER, MA TI THE COLLISION ZONE BETWEEN THE NORTH DENTRECASTEAUX RIDGE AND THE NEW HEBRIDES ISLAND-ARC .1. SEA BEAM MORPHOLOGY AND SHALLOW STRUCTURE SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID ACCRETIONARY WEDGES; LOUISVILLE RIDGE; MALEKULA ISLANDS; FRACTURE-ZONE; TONGA TRENCH; JAPAN TRENCH; SUBDUCTION; VANUATU; SEISMICITY; TECTONICS AB Sea Beam bathymetric data, closely spaced single-channel seismicreflection sections, and geopotential field data were collected aboard the R/VJ. Charcot over the collision zone between the North d'Entrecasteaux Ridge (NDR) and the New Hebrides island arc. The NDR trends east at a small angle (14-degrees) to the plate convergence direction so that the ridge creeps northward along the trench at about 2.5 cm/yr, requiring a continual structural adjustment of the accretionary complex. In this report we study the shallow structure, tectonic erosion, and consequent mass wasting of the accretionary complex, all of which were produced by the collision of the NDR in a complex deformational environment. The accretionary complex in this collision zone can be divided into nothern, central, and southern parts. The northern part of the collision zone, which lies north of the leading flank of the ridge, shows a lobate lower accretionary complex that is structured by east to southeast dipping thrust and reverse faults and N60-degrees-W trending strike-slip faults; a middle accretionary complex that bulges seaward and appears to be rotated 45-degrees-E from the regional arc trend; and an upper accretionary complex that is shaped by slumps and a canyon network. The central part of the collision zone, which directly overlies the crest of the ridge, forms a broad shallow protrusion that is bounded on its northern and southern sides by steep scarps. Rocks forming this protrusion have been uplifted, possibly by as much as 1500-2500 m, and tilted to the north, causing northward block sliding along an extensional detachment surface. The southern part of the collision zone, which lies in the wake of the ridge, is deformed by large slumps and normal faults that trend parallel to the ridge axis. Rocks forming this southern part collapse, causing widespread mass wasting. These geophysical data indicate that normal trench convergence has apparently produced only a few trench-parallel structures confined to the toe of the accretionary complex, whereas the along-trench motion of the NDR has resulted in well-developed structures that extend obliquely across the arc slope and form an asymmetric tectonic pattern. The area of the accretionary complex that is disturbed by collision appears to be about twice as wide as the width of the NDR, and the time required to heal the disturbance may be about 0.8 m.y. C1 US GEOL SURVEY,MENLO PK,CA 94025. RP COLLOT, JY (reprint author), ORSTOM,GEODYNAM LAB,BP 48,F-06230 VILLEFRANCHE MER,FRANCE. NR 49 TC 21 Z9 21 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 4457 EP 4478 DI 10.1029/90JB01935 PG 22 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300042 ER PT J AU FISHER, MA COLLOT, JY GEIST, EL AF FISHER, MA COLLOT, JY GEIST, EL TI THE COLLISION ZONE BETWEEN THE NORTH DENTRECASTEAUX RIDGE AND THE NEW HEBRIDES ISLAND-ARC .2. STRUCTURE FROM MULTICHANNEL SEISMIC DATA SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS LA English DT Article ID SOUTHWEST PACIFIC; MALEKULA ISLANDS; SUBDUCTION; EVOLUTION; MOVEMENTS; SANTO AB The d'Entrecasteaux zone (DEZ) collides with the central New Hebrides island arc and consists of two subparallel ridges that strike east-west, stand 1-2 km above the surrounding oceanic plate, and subduct obliquely (15-degrees) northward beneath the arc. Rocks dredged from the north ridge as well as reflections evident in multichannel seismic reflection data indicate that this ridge has a volcanic origin. Crystalline volcanic rocks are common along the lower flank of the ridge, but sedimentary, probably volcaniclastic, rock caps the ridge. Seismic reflection data collected over the lower arc slope reveal that mass wasting deposits locally make up most of the accretionary wedge. These deposits appear to form discrete bodies, suggesting that mass wasting occurred episodically. Large anticlines and thrust faults having large vertical separation are not readily evident where the colliding ridge intersects the arc slope; apparently, slope rocks have low strength so that mass wasting deposits formed instead of large-relief structures. Mass wasting is thought to occur as the accretionary wedge is uplifted in response to the northward oblique subduction of the north ridge. The toe of the north ridge flank marks an abrupt transition in the lithologies that make up the footwall of the interplate decollement. Footwall lithologies change from ocean basin to volcaniclastic ridge material, and this transition probably marks a discontinuity in friction along the decollement or in rock mechanical properties because north of the transition, thrust faults deform the accretionary wedge whereas south of the transition, steep reverse faults crosscut the wedge and pierce the north flank of the ridge. This piercement means that the decollement at least locally lies within the ridge and that ridge material exotic to the New Hebrides arc may be incorporated into the accretionary wedge. C1 ORSTOM,GEODYNAM LAB,F-06230 VILLEFRANCHE MER,FRANCE. RP FISHER, MA (reprint author), US GEOL SURVEY,MS 999,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. NR 35 TC 14 Z9 14 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-SOLID PD MAR 10 PY 1991 VL 96 IS B3 BP 4479 EP 4495 DI 10.1029/90JB00715 PG 17 WC Geosciences, Multidisciplinary SC Geology GA FB313 UT WOS:A1991FB31300043 ER PT J AU LOCKNER, DA BYERLEE, JD KUKSENKO, V PONOMAREV, A SIDORIN, A AF LOCKNER, DA BYERLEE, JD KUKSENKO, V PONOMAREV, A SIDORIN, A TI QUASI-STATIC FAULT GROWTH AND SHEAR FRACTURE ENERGY IN GRANITE SO NATURE LA English DT Article ID EARTHQUAKE; MODEL AB The failure process in a brittle granite sample can be stabilized by controlling axial stress to maintain a constant rate of acoustic emission. As a result, the post-failure stress curve can be followed quasi-statically, extending to hours the fault growth process which normally would occur violently in a fraction of a second. Using a procedure originally developed to locate earthquakes, acoustic emission arrival-time data are inverted to obtain three-dimensional locations of microseisms. These locations provide a detailed view of fracture nucleation and growth. C1 AF IOFFE PHYSICOTECH INST,LENINGRAD 194021,USSR. ACAD SCI USSR,INST PHYS EARTH,MOSCOW 123810,USSR. RP LOCKNER, DA (reprint author), US GEOL SURVEY,345 MIDDLEFIELD RD,MENLO PK,CA 94025, USA. RI Ponomarev, Alexander/J-7767-2013; Kuksenko, Victor/M-7793-2014 NR 15 TC 373 Z9 405 U1 6 U2 35 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD MAR 7 PY 1991 VL 350 IS 6313 BP 39 EP 42 DI 10.1038/350039a0 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA FA693 UT WOS:A1991FA69300055 ER PT J AU ELLIOTT, WC ARONSON, JL MATISOFF, G GAUTIER, DL AF ELLIOTT, WC ARONSON, JL MATISOFF, G GAUTIER, DL TI KINETICS OF THE SMECTITE TO ILLITE TRANSFORMATION IN THE DENVER BASIN - CLAY MINERAL, K-AR DATA, AND MATHEMATICAL-MODEL RESULTS SO AAPG BULLETIN LA English DT Article ID DIAGENESIS; BENTONITE; ILLITIZATION; GENERATION; MECHANISM; SHALES; TEXAS AB Clay mineral data, potassium-argon (K-Ar) ages, and mathematical model simulations indicate the important kinetic factors controlling the smectite to illite transformation ("illitization") in Upper Cretaceous Mowry and Niobrara core and outcrop bentonites from the Denver basin. The data also provide additional information on the thermal history of the basin. Data show that both the percentages of illite layers and the K-Ar ages of mixed layer illite-smectite (I/S) increase with increasing depths of burial, and this trend was simulated mathematically employing a very simplified burial model with a fifth-order overall kinetic expression for the formation of illite. For most of the basin, the data is compatible with I/S having been formed in response to increased temperature from progressive burial, because the oldest K-Ar ages of I/S are from the deepest buried I/S along the basin axis. In addition, these data qualitatively suggest that I/S even as small as < 0.1-mu-m retains radiogenic argon under Denver basin burial temperatures. I/S separated from drill core bentonites from the Wattenberg gas field, astride the basin axis and known to have been subjected to an anomalously high temperature history, are the most illitic and among the oldest measured from core in this study. The ages of illitization (about 60 Ma) are coincident with the Laramide time of structural development of the basin and uplift of the Front Range. The reconstructions of the burial history, and the modelling of the timing and extent of illitization, suggest that the area of the Wattenberg gas field was an upper Cretaceous depocenter, an area of relatively deeper burial along the basin axis. However, the data can not rule out the possibility that these sediments at and near the Wattenberg gas field were heated not only by burial but also by igneous and related hydrothermal activity associated with the Colorado mineral belt during the Laramide uplift (70-45 Ma) of the Front Range. Likewise, the anomalously illitic I/S in outcrop bentonites along the Front Range adjacent to the Wattenberg gas field may have been formed in response either to deep burial and/or by Laramide-age secondary heating superimposed on burial. C1 US GEOL SURVEY, DENVER FED CTR, DENVER, CO 80225 USA. RP ELLIOTT, WC (reprint author), CASE WESTERN RESERVE UNIV, DEPT GEOL SCI, CLEVELAND, OH 44106 USA. NR 49 TC 49 Z9 51 U1 1 U2 5 PU AMER ASSOC PETROLEUM GEOLOGIST PI TULSA PA 1444 S BOULDER AVE, PO BOX 979, TULSA, OK 74119-3604 USA SN 0149-1423 EI 1558-9153 J9 AAPG BULL JI AAPG Bull. PD MAR PY 1991 VL 75 IS 3 BP 436 EP 462 PG 27 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700003 ER PT J AU BALL, MM AF BALL, MM TI REASSESSMENT OF THE BAHAMAS FRACTURE-ZONE SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,EVERGREEN,CO. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 537 EP 537 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700033 ER PT J AU BARKER, CE DAIZIEL, MC AF BARKER, CE DAIZIEL, MC TI USING CATHODOLUMINESCENCE TO MAP REGIONALLY ZONED CARBONATE CEMENTS OCCURRING IN DIAGENETIC AUREOLES ABOVE OIL-RESERVOIRS, VELMA OIL-FIELD, OKLAHOMA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 538 EP 538 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700038 ER PT J AU BARTON, CC SCHOLZ, CH SCHUTTER, TA HERRING, PR THOMAS, WJ AF BARTON, CC SCHOLZ, CH SCHUTTER, TA HERRING, PR THOMAS, WJ TI FRACTAL NATURE OF HYDROCARBON DEPOSITS .2. SPATIAL-DISTRIBUTION SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. COLUMBIA UNIV,LAMONT DOHERTY GEOL OBSERV,PALISADES,NY 10964. COLUMBIA UNIV,DEPT GEOL SCI,PALISADES,NY 10964. NR 0 TC 4 Z9 4 U1 1 U2 2 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 539 EP 539 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700041 ER PT J AU BIRD, KJ AF BIRD, KJ TI THE ELLESMERIAN PETROLEUM SYSTEM - NORTH SLOPE OF ALASKA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,MENLO PK,CA 94025. NR 0 TC 0 Z9 0 U1 0 U2 6 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 542 EP 542 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700057 ER PT J AU CLARKE, JW AF CLARKE, JW TI DAULETABAD-DONMEZ GAS-FIELD, USSR SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 553 EP 554 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700107 ER PT J AU CLARKE, JW AF CLARKE, JW TI SAMOTLOR OIL-FIELD, WEST SIBERIA, USSR SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 554 EP 554 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700109 ER PT J AU CLARKE, JW AF CLARKE, JW TI PETROLEUM GEOLOGY OF EAST SIBERIA SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,RESTON,VA 22092. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 554 EP 554 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700108 ER PT J AU CLAYTON, JL KONCA, I AF CLAYTON, JL KONCA, I TI APPLICATION OF ORGANIC GEOCHEMISTRY TO PETROLEUM-EXPLORATION IN BEKES BASIN, HUNGARY SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,DENVER,CO 80225. HUNGARIAN HYDROCARBON IND SCI IND ASSOC,SZAZHALOMBATTA,HUNGARY. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 554 EP 554 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700110 ER PT J AU COOK, HE TAYLOR, ME AF COOK, HE TAYLOR, ME TI CARBONATE-SLOPE FAILURES AS INDICATORS OF SEA-LEVEL LOWERINGS SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 US GEOL SURVEY,MENLO PK,CA 94025. US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 5 Z9 5 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 556 EP 556 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700118 ER PT J AU DAMUTH, JE OLSON, HC TWICHELL, DC AF DAMUTH, JE OLSON, HC TWICHELL, DC TI NEOGENE DEPOSITIONAL PROCESSES ON THE TEXAS-LOUISIANA CONTINENTAL-SLOPE REVEALED BY HIGH-RESOLUTION SEISMIC STUDIES SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 MOBIL RES & DEV CORP,DALLAS,TX. US GEOL SURVEY,WOODS HOLE,MA 02543. RI Olson, Hilary/G-6150-2010 NR 0 TC 3 Z9 3 U1 0 U2 0 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 560 EP 561 PG 2 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700138 ER PT J AU DILL, RF HALLEY, RB SHINN, EA KINDINGER, JL MUHS, DR AF DILL, RF HALLEY, RB SHINN, EA KINDINGER, JL MUHS, DR TI ELEVATED REEFS AND RELATED PLEISTOCENE STRATIGRAPHY OF THE SOUTHERN EXUMA ISLANDS, BAHAMAS SO AAPG BULLETIN-AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS LA English DT Meeting Abstract C1 UNIV S CAROLINA,COLUMBIA,SC 29208. CARIBBEAN MARINE RES CTR,SAN DIEGO,CA. US GEOL SURVEY,ST PETERSBURG,FL. US GEOL SURVEY,DENVER,CO 80225. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSN PETROL GEOLOGISTS PI TULSA PA 1444 S BOULDER AVE PO BOX 979, TULSA, OK 74101 SN 0149-1423 J9 AAPG BULL JI AAPG Bull.-Am. Assoc. Petr. Geol. PD MAR PY 1991 VL 75 IS 3 BP 563 EP 563 PG 1 WC Geosciences, Multidisciplinary SC Geology GA FA437 UT WOS:A1991FA43700147 ER EF