Paleomagnetism of the Siberian flood basalts of the Noril'sk area: A constraint on eruption duration
Edward N. Lind, Sergey V. Kropotov, Gerald K. Czamanske, Sherman Gromme, V.A. Fedorenko
1994, International Geology Review (36) 1139-1150
The volcanic sequence of the Noril'sk area, northern Siberia, provides the most complete section of early Siberian flood-basalt volcanism. Paleomagnetic measurements for more than 4000 samples of lava and tuff indicate that nearly all of this >3500-m-thick sequence was laid down during one interval of normal magnetic polarity. Lavas of...
Mineralogy, paragenesis, and mineral zoning of the Bulldog Mountain vein system, Creede District, Colorado
Geoffrey S. Plumlee, Pamela Heald Whitehouse-Veaux
1994, Economic Geology (89) 1883-1905
The Bulldog Mountain vein system, Creede district, Colorado, is one of four major epithermal vein systems from which the bulk of the district's historical Ag-Pb-Zn-Cu production has come. Ores deposited along the vein system were discovered in 1965 and were mined from 1969 to 1985.Six temporally gradational mineralization stages have...
Uranium(VI) adsorption to ferrihydrite: Application of a surface complexation model
T.D. Waite, J.A. Davis, T.E. Payne, G.A. Waychunas, N. Xu
1994, Geochimica et Cosmochimica Acta (58) 5465-5478
A study of U(VI) adsorption by ferrihydrite was conducted over a wide range of U(VI) concentrations, pH, and at two partial pressures of carbon dioxide. A two-site (strong- and weak-affinity sites, FesOH and FewOH, respectively) surface complexation model was able to describe the experimental data well over a wide range...
Are all prey created equal? A review and synthesis of differential predation on prey in substandard condition
Matthew G. Mesa, Thomas P. Poe, Dena M. Gadomski, James H. Petersen
1994, Journal of Fish Biology (45) 81-96
Our understanding of predator-prey interactions in fishes has been influenced largely by research assuming that the condition of the participants is normal. However, fish populations today often reside in anthropogenically altered environments and are subjected to many kinds of stressors, which may reduce their ecological performance by adversely affecting their...
Assessment of spatial variability of major-ion concentrations and del oxygen-18 values in surface snow, Upper Fremont Glacier, Wyoming, USA
D. L. Naftz, P. F. Schuster, M.M. Reddy
1994, Hydrology Research (25) 371-388
One hundred samples were collected from the surface of the Upper Fremont Glacier at equally spaced intervals defined by an 8,100 m2 snow grid to assess the significance of lateral variability in major-ion concentrations and del oxygen-18 values. For the major ions, the largest concentration range within the snow grid was...
Spatial variability in biodegradation rates as evidenced by methane production from an aquifer
Neal R. Adrian, Joseph A. Robinson, Joseph M. Suflita
1994, Applied and Environmental Microbiology (60) 3632-3639
Accurate predictions of carbon and energy cycling rates in the environment depend on sampling frequencies and on the spatial variability associated with biological activities. We examined the variability associated with anaerobic biodegradation rates at two sites in an alluvial sand aquifer polluted by municipal landfill leachate. In situ rates of...
Flow path studies in forested watersheds of headwater tributaries of Brush Brook, Vermont
Donald S. Ross, R. J. Bartlett, Frederick R. Magdoff, Gregory J. Walsh
1994, Water Resources Research (30) 2611-2618
An investigation was undertaken into how headwater tributaries of Brush Brook, Vermont, could have average pH differences of almost two units (4.75 and 6.7). Sampling along four tributaries revealed that most of one tributary, below an area of seeps, had consistently higher pH, Ca2+, Mg2+, and K+, and lower Al than other...
Problems of stock definition in estimating relative contributions of Atlantic striped bass to the coastal fishery
John R. Waldman, Mary C. Fabrizio
1994, Transactions of the American Fisheries Society (123) 766-778
Stock contribution studies of mixed‐stock fisheries rely on the application of classification algorithms to samples of unknown origin. Although the performance of these algorithms can be assessed, there are no guidelines regarding decisions about including minor stocks, pooling stocks into regional groups, or sampling discrete substocks to...
Crustal velocity structure of the northern Yukon-Tanana upland, central Alaska: Results from TACT refraction/wide-angle reflection data
Bruce C. Beaudoin, Gary S. Fuis, William J. Lutter, Walter D. Mooney, Thomas E. Moore
1994, Bulletin (106) 981-1001
The Fairbanks North seismic refraction/ wide-angle reflection profile, collected by the U.S. Geological Survey Trans-Alaska Crustal Transect (TACT) project in 1987, crosses the complex region between the Yukon-Tanana and Ruby terranes in interior Alaska. This region is occupied by numerous small terranes elongated in a northeast-southwest direction. These seismic data...
Isotopic composition of Pb in ore deposits of the Betic Cordillera, Spain; origin and relationship to other European deposits
Antonio Arribas , Richard M. Tosdal
1994, Economic Geology (89) 1074-1093
The Betic Cordillera in southern Spain is a complex Alpine fold belt that resulted from the Cretaceous through Cenozoic collision of Africa with Europe. The region is illustrative of one of the characteristics of the Alpine-Mediterranean orogen: the occurrence over a limited area of mineral deposits with a wide variety...
Satellite tobacco mosaic virus sequence variants with only five Nucleotide differences can interfere with each other in a cross protection-like phenomenon in plants
Gael Kurath, J. Allan Dodds
1994, Virology (202) 1065-1069
The type strain of satellite tobacco mosaic virus (STMV) contains two major variants, designated type 5 (T5) and type 6 (T6), which can be easily distinguished by RNase protection analyses. Clones containing cDNA of representative T5 and T6 STMV genomes have only five single-base differences in the entire 1059-nucleotide genome,...
Measurements of P and S wave fronts from the dense three-dimensional array at Garni, Armenia
Jim Mori, John R. Filson, Edward Cranswick, Roger D. Borcherdt, Ruben Amirbekian, Vigen Aharonian, Leon Hachverdian
1994, Bulletin of the Seismological Society of America (84) 1089-1096
The P- and S-wave arrivals from local earthquakes were studied using an array of 10 three-component instruments in and around a tunnel at Garni Observatory, Armenia. The array has a three-dimensional configuration with lateral dimensions of 300 to 500 m and a depth extent of 100 m. Estimates of the...
Team investigates activity at Mt. Semeru, Java, volcano
Peggy Hellweg, Deiter Seidl, Kirbani Sri Brotopuspito, Wolfgang Brustle
1994, Eos, American Geophysical Union (75) 313-317
In February 1994 a large eruption continued a pattern of activity that Mt. Semeru volcano—the highest mountain in Java, Indonesia—has exhibited since 1967. Mt. Semeru lies south of the Tengger Caldera, which encloses the volcano Mt. Bromo. Together, they form one of the largest volcanic complexes in the province of...
Marginal bed load transport in a gravel bed stream, Sagehen Creek, California
E.D. Andrews
1994, Water Resources Research (30) 2241-2250
Marginal bed load transport describes the condition when relatively few bed particles are moving at any time. Bed particles resting in the shallowest bed pockets will move when the dimensionless shear stress т* exceeds a value of about 0.020. As т* increases, the number of bed particles moving increases. Significant motion of...
Aquatic invertebrate production in southeastern USA wetlands during winter and spring
Walter G. Duffy, Douglas LaBar
1994, Wetlands (14) 88-97
We measured aquatic invertebrate abundance, standing stock biomass, and community production in three types of wetlands on Noxubee National Wildlife Refuge from December 1987 through April 1988. Together, Orthocyclops modestus and Daphnia pulex were the most abundant organisms collected in all habitats during both winter and spring, but each contributed little to total standing...
Piezometer performance at Wildlife liquefaction site, California
T. Leslie Youd, Thomas L. Holzer
1994, Journal of Geotechnical Engineering (120) 975-995
In response to an urgent need for field data from instrumented liquefaction sites, the U.S. Geological Survey in 1982 selected and instrumented a site in southern California called the Wildlife site. Two accelerometers (one at ground surface and one at a depth of 7.5 m) and six electrical pore‐pressure transducers...
Petrogenesis of the highly potassic 1.42 Ga Barrel Spring pluton, southeastern California, with implications for mid-Proterozoic magma genesis in the southwestern USA
James D. Gleason, Calvin F. Miller, J. L. Wooden, Victoria C. Bennett
I. S. E. Carmichael, editor(s)
1994, Contributions to Mineralogy and Petrology (118) 182-197
Syenites from the Barrel Spring pluton were emplaced in the Early Proterozoic Mojave crustal provine of southeastern California at 1.42 Ga. All rocks, even the most mafic, are highly enriched in incompatible elements (e.g. K2O 4–12 wt%, Rb 170–370 ppm, Th 12–120 ppm, La 350–1500xchondrite, La/Ybn 35–100)....
Ammonium sorption to channel and riparian sediments: A transient storage pool for dissolved inorganic nitrogen
Frank J. Triska, Alan P. Jackman, John H. Duff, Ronald J. Avanzino
1994, Biogeochemistry (26) 67-83
Sediment (0.5 mm–2.0 mm grain size) was incubated in nylon bags (200 μm mesh) below the water table in the channel and in two transects of shallow wells perpendicular to the banks (to 18 m) of a third-order stream during August, 1987. One transect of wells drained steep old-growth forest,...
Dense array recordings in the San Bernardino Valley of landers-big bear aftershocks: Basin surface waves, Moho reflections, and three-dimensional simulations
Arthur Frankel
1994, Bulletin of the Seismological Society of America (84) 613-624
Fourteen GEOS seismic recorders were deployed in the San Bernardino Valley to study the propagation of short-period (T ≈ 1 to 3 sec) surface waves and Moho reflections. Three dense arrays were used to determine the direction and speed of propagation of arrivals in the seismograms. The seismograms for...
Local observations of the onset of a large earthquake: 28 June 1992 Landers, California
Richael Abercrombie, Jim Mori
1994, Bulletin of the Seismological Society of America (84) 725-734
The Landers earthquake (MW 7.3) of 28 June 1992 had a very emergent onset. The first large amplitude arrivals are delayed by about 3 sec with respect to the origin time, and are preceded by smaller-scale slip. Other large earthquakes have been observed to have similar emergent onsets, but the...
Earthquake refraction profiles of the root of the Sierra Nevada
Martha K. Savage, Li Li, Jerry P. Eaton, Craig H. Jones, James N. Brune
1994, Tectonics (13) 803-817
We examine the seismic structure of the Sierra Nevada using records of nine earthquakes and one explosion in and near the Sierra, recorded on stations in the Sierra. We first interpret travel times from these paths, which are confined to a single tectonic block, in terms of...
Microfossil biostratigraphy of prograding Neogene platform-margin carbonates, Bahamas: Age constraints and alternatives
Barbara H. Lidz, Timothy J. Bralower
1994, Marine Micropaleontology (23) 265-344
Benthic and planktic foraminifera and calcareous nannofossils were recovered in shallow-water carbonate rock cores from two continuous boreholes drilled 7.5 km apart on the west platform margin of the Great Bahama Bank. The microfossils define six biostratigraphic units in each hole. One unit in each hole represents a correlative condensed...
Effects of sample isolation and handling on the recovery of purgeable organic compounds
Jacob Gibs, Thomas E. Imbrigiotta, James H. Ficken, James F. Pankow, M. E. Rosen
1994, Ground Water Monitoring and Remediation (14) 142-152
This report compares the recovery of purgeable organic compounds (POCs) obtained by using a downhole isobaric sampler developed by the U.S. Geological Survey, a helical-rotor submersible pump, and a point source bailer to collect and isolate samples of ground water from three wells in Now York and New Jersey: the...
Humic and fulvic acids: sink or source in the availability of metals to the marine bivalves Macoma balthicaand Potamocorbula amurensis?
Alan Decho, Samuel N. Luoma
1994, Marine Ecology Progress Series (108) 133-145
Humic acids (HA) and fulvic acids (FA) are common forms of organic matter in marine sedirnents, and are routinely ingested by deposit- and suspension-feeding animals. These compounds may be a sink for metals, implying that once metals are bound to humic substances they are no longer available to food webs....
Surface energy balance estimates at local and regional scales using optical remote sensing from an aircraft platform and atmospheric data collected over semiarid rangelands
William P. Kustas, M. S. Moran, K.S. Humes, D.I. Stannard, P. J. Pinter Jr., L.E. Hipps, E. Swiatek, D.C. Goodrich
1994, Water Resources Research (30) 1241-1259
Remotely sensed data in the visible, near-infrared, and thermal-infrared wave bands were collected from a low-flying aircraft during the Monsoon '90 field experiment. Monsoon '90 was a multidisciplinary experiment conducted in a semiarid watershed. It had as one of its objectives the quantification of hydrometeorological fluxes during the...
