Origin of deep crystal reflections: Seismic profiling across high-grade metamorphic terranes in Canada
A. Green, Bernd Milkereit, J. Percival, A. Davidson, R. Parrish, F. Cook, W. Geis, W. Cannon, D. Hutchinson, G. West, R. Clowes
1990, Tectonophysics (173) 627-638
In an attempt to better understand the origin of deep crustal reflections LITHOPROBE has sponsored or co-sponsored Seismic reflection surveys across tracts of high-grade metamorphic rock in the Archean Superior craton, the Proterozoic Grenville orogen and the Phanerozoic Cordilleran orogen. Common to these three diverse terranes are near-surface zones of...
Regional flood-frequency relations for streams with many years of no flow
Hjalmar W. Hjalmarson, Blakemore E. Thomas
French Richard H., editor(s)
1990, Conference Paper, Hydraulics/Hydrology of Arid Lands
In the southwestern United States, flood-frequency relations for streams that drain small arid basins are difficult to estimate, largely because of the extreme temporal and spatial variability of floods and the many years of no flow. A method is proposed that is based on the station-year method. The new method...
Maceral and palynomorph facies from two tertiary peat-forming environments in the Powder River Basin, U.S.A.
T.A. Moore, R.W. Stanton, D.T. Pocknall, R.M. Glores
1990, International Journal of Coal Geology (15) 293-316
The differences between the depositional settings of the Smith and Anderson subbituminous coal beds (Paleocene, central Powder River Basin, U.S.A.) are interpreted on the basis of their petrographic composition and palynologic assemblages. The Smith coal bed is relatively thin <span id="MathJax-Element-1-Frame"...
Cryogenic preservation of semen from the Aleutian Canada goose (Branta canadensis leucopareia)
G.F. Gee, Thomas J. Sexton
1990, Zoo Biology (9) 361-371
Aleutian Canada geese (Branta canadensis leucopareia) were inseminated with frozen-thawed semen containing 6% or 7% dimethylsulfoxide (DMSO) resulting in 32 fertile eggs and 17 goslings; with 7% DMSO, 19 of 31 eggs were fertile. Beltsville Poultry Semen Extender (BPSE), adjusted to 270 ± 30 mOs and 7.5 ± 0.4 pH,...
Use of dietary yeast Saccharomyces cerevisiae nitrogen by lake trout
G. L. Rumsey, S. G. Hughes, John L. Kinsella
1990, Journal of the World Aquaculture Society (21) 205-209
In a 12 week experiment, lake trout (Salvelinus namaycush) were fed diets in which 50% of the nitrogen was provided by one of six preparations of Saccharomyces yeast. Fish fed baker's yeast with disrupted cell walls grew at a rate equal to that of fish fed the control diet and faster than...
Infrared spectra and crystal chemistry of scapolites: implications for Martian mineralogy
Gregg A. Swayze, Roger N. Clark
1990, Journal of Geophysical Research (95) 14481-14495
Near‐infrared and midinfrared spectra of a wide range of scapolite compositions were studied to determine the cause of the 2.36‐μm features that have been correlated with similar features in the near‐IR spectrum of Mars. We attribute the 2.36−μm features to vibrations caused by HCO3− and HSO4− in the anion sites of scapolite....
Geochemical evidence for Se mobilization by the weathering of pyritic shale, San Joaquin Valley, California, U.S.A.
T. S. Presser, W. C. Swain
1990, Applied Geochemistry (5) 703-717
Acidic (pH 4) seeps issue from the weathered Upper Cretaceous-Paleocene marine sedimentary shales of the Moreno Formation in the semi-arid Coast Ranges of California. The chemistry of the acidic solutions is believed to be evidence of current reactions ultimately yielding hydrous...
Recent uplift and hydrothermal activity at Tangkuban Parahu volcano, west Java, Indonesia
J. Dvorak, J. Matahelumual, A.T. Okamura, H. Said, T. J. Casadevall, D. Mulyadi
1990, Bulletin of Volcanology (53) 20-28
Tangkuban Parahu is an active stratovolcano located 17 km north of the city of Bandung in the province west Java, Indonesia. All historical eruptive activity at this volcano has been confined to a complex of explosive summit craters. About a dozen eruptions-mostly phreatic events- and 15 other periods of unrest,...
Fractal characterization of fracture surfaces in concrete
V. E. Saouma, Christopher C. Barton, N. A. Gamaleldin
1990, Engineering Fracture Mechanics (35) 47-53
Fractal geometry is used to characterize the roughness of cracked concrete surfaces through a specially built profilometer, and the fractal dimension is subsequently correlated to the fracture toughness and direction of crack propagation. Preliminary results indicate that the fracture surface is indeed fractal over two orders of magnitudes with a...
The Stillwater Complex and its anorthosites: an accident of magmatic underplating?
G.K. Czamanske, S.R. Bohlen
1990, American Mineralogist (75) 37-45
The Stillwater Complex, emplaced 2700??40 Ma, is exposed at the edge of a 4000-km2 block of Late Archean rocks that formed 40 to 110 m.y. yearlier. Voluminous plagioclase cumulates (anorthosites) within the Middle Banded series of the complex are difficult to explain either by in situ fractionation of mafic magma...
Natural sources of greenhouse gases: carbon dioxide emissions from volcanoes
Terrence Gerlach
1990, Conference Paper, Transactions - Geothermal Resources Council
Volcanic degassing of carbon dioxide plays an important role in keeping the atmosphere-ocean portion of the carbon geochemical cycle in balance. The atmosphere-ocean carbon deficit requires replenishment of 6??1012 mol CO2/yr, and places an upper limit on the output of carbon dioxide from volcanoes. The CO2 output of the global...
Pleistocene stratigraphy of the Boston Harbor drumlins, Massachusetts
W.A. Newman, R. C. Berg, P.S. Rosen, H.D. Glass
1990, Quaternary Research (34) 148-159
Evidence from the Boston Harbor drumlins indicates that two superposed tills were deposited during glacier advances which were separated by a long nonglacial interval. At Long and Peddocks Islands, argillans and truncated clay-filled fractures, along with discontinuities in clay-mineral composition, define the till contacts. Physical indicators separating the tills are...
Ages and stable-isotope compositions of secondary calcite and opal in drill cores from Tertiary volcanic rocks of the Yucca Mountain area, Nevada
Barney J. Szabo, T.K. Kyser
1990, Geological Society of America Bulletin (102) 1714-1719
Stable-isotope compositions of fracture-and cavity-filling calcite from the unsaturated zone of three drill cores at Yucca Mountain Tertiary volcanic complex indicate that the water from which the minerals precipitated was probably meteoric in origin. A decrease in 18O in the calcite with depth is...
A comparison of two- and three-dimensional stochastic models of regional solute movement
A.M. Shapiro, V.D. Cvetkovic
1990, Transport in Porous Media (5) 1-25
Recent models of solute movement in porous media that are based on a stochastic description of the porous medium properties have been dedicated primarily to a three-dimensional interpretation of solute movement. In many practical problems, however, it is more convenient and consistent with measuring techniques to consider flow and solute...
Distribution and transport of sediment-bound metal contaminants in the Rio Grande de Tarcoles, Costa Rica (Central America)
C. C. Fuller, J.A. Davis, D.J. Cain, P. J. Lamothe, T.L.G. Fries Fernandez, J.A. Vargas, M.M. Murillo
1990, Water Research (24) 805-812
A reconnaissance survey of the extent of metal contamination in the Rio Grande de Tarcoles river system of Costa Rica indicated high levels of chromium (Cr) in the fine-grain bed sediments (<60 μm) of tributaries downstream from leather tanneries (50–83 times Cr background or 3000–5000 μg/g). In the main channel of...
Teleseismic tomography of the compressional wave velocity structure beneath the Long Valley region, California
P.B. Dawson, J.R. Evans, H. M. Iyer
1990, Journal of Geophysical Research Solid Earth (95) 11021-11050
In 1982 and 1984 the U.S. Geological Survey used several seismic networks, totaling over 90 stations, to record teleseismic P waves and measure travel time residuals in an area centered on the Long Valley caldera. We inverted the travel time residuals to obtain a three-dimensional image of the velocity structure with resolution...
Factors controlling late Cenozoic continental margin growth from the Ebro Delta to the western Mediterranean deep sea
C.H. Nelson, A. Maldonado
1990, Marine Geology (95) 419-440
The Ebro continental margin sedimentation system originated with a Messinian fluvial system. This system eroded both a major subaerial canyon cutting the margin southeastward from the present Ebro Delta and an axial valley that drained northeastward down Valencia Trough. Post-Messinian submergence...
Fractionation of palladium and platinum in a Mesozoic diabase sheet, Gettysburg basin, Pennsyvania: Implications for mineral exploration
D. Gottfried, A.J. Froelich, N. Rait, P. J. Aruscavage
1990, Journal of Geochemical Exploration (37) 75-89
The York Haven diabase sheet displays clear-cut evidence of fractionation of Pd and Pt during differentiation of a high-Ti (about 1.1%) quartz-normative tholeiitic magma (York Haven type). At York Haven the sheet is about 750 m thick. It is characterized by abundant cumulus MgO-rich orthopyroxene (bronzite), and is markedly depleted...
Seismicity following the 1985 eruption of Nevado del Ruiz, Colombia
J.E. Zollweg
1990, Journal of Volcanology and Geothermal Research (41) 355-367
Over 200 of the best-recorded earthquakes occurring near Nevado del Ruiz, Colombia, between December 1985 and May 1986 are examined for spatial patterns, information on local stress orientations, and evidence for seismogenic structures that may be related to magma-transport processes. These earthquakes occurred following the devastating eruption of November 13,...
A monitor for continuous measurement of temperature, pH, and conductance of wet precipitation: Preliminary results from the Adirondack Mountains, New York
P.A. Johnsson, M.M. Reddy
1990, Atmospheric Environment - Part A General Topics (24A) 233-236
This report describes a continuous wet-only precipitation monitor designed by the U.S. Geological Survey to record variations in rainfall temperature, pH, and specific conductance at 1-min intervals over the course of storms. Initial sampling in the Adirondack Mountains showed that rainfall acidity varied over the course of summer storms, with...
Intragranular diffusion: An important mechanism influencing solute transport in clastic aquifers?
W.W. Wood, T. F. Kraemer, P.P. Hearn Jr.
1990, Science (247) 1569-1572
Quantification of intragranular porosity in sand-size material from an aquifer on Cape Cod, Massachusetts, by scanning electron microscopy, mercury injection, and epifluorescence techniques shows that there are more reaction sites and that porosity is greater that indicated by standard short-term laboratory tests and measurement techniques. Results from laboratory and field...
Thermal infrared exploration in the Carlin trend, northern Nevada
K. Watson, F.A. Kruse, S. Hummer-Miller
1990, Geophysics (55) 70-79
Experimental Thermal Infrared Multispectral Scanner (TIMS) aircraft data have been acquired for the Rodeo Creek NE 7 1/2 minute quadrangle, Eureka County, northern Nevada, covering the Carlin gold mine. A simple model has been developed to extract spectral emissivities for mapping surface lithology and alteration based on the physical properties...
Controls on porphyrin concentrations of Pennsylvanian organic-rich shales, Western U.S.A.
J.L. Clayton, G.E. Michael
1990, Energy & Fuels (4) 644-646
Organic-rich black shales of Middle Pennsylvanian (Desmoinesian) age occur over much of the central U.S. and as far west as the northern Denver and southeastern Powder River basins. Total organic carbon contents (Corg) are commonly greater than 10 wt %. Porphyrin concentrations (vanadyl + nickel) are as high as 40000...
Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines
T.A. Abrajano, N.C. Sturchio, B. M. Kennedy, G.L. Lyon, K. Muehlenbachs, J.K. Böhlke
1990, Applied Geochemistry (5) 625-630
Methane-hydrogen gas seeps with mantle-like C and noble gas isotopic characteristics issue from partially serpentinized ultramafic rocks in the Zambales ophiolite, Philippines. New measurements of noble gas and 14C isotope abundances, rock/mixed-volatile equilibrium calculations, and previous chemical and isotopic data suggest that these reduced gases are products of periodotite hydration....
Bulldozing and resuspension of shallow-shelf sediment by ice keels: Implications for Arctic sediment transport trajectories
D.M. Rearic, P. W. Barnes, E. Reimnitz
1990, Marine Geology (91) 133-147
The orientations and termination directions of newly formed ice gouges, identified in a 5-year study of two offshore corridors in eastern Harrison Bay, Alasaka, indicate a bimodal distribution of sediment transport directions: west-southwest and southeast, due to ice-keel bulldozing. The westerly sediment...
