Geochemistry of vanadium in an epigenetic, sandstone-hosted vanadium-uranium deposit, Henry Basin, Utah
R. B. Wanty, M. B. Goldhaber, H. R. Northrop
1990, Economic Geology (85) 270-284
The epigenetic Tony M vanadium-uranium orebody in south-central Utah is hosted in fluvial sandstones of the Morrison Formation (Upper Jurassic). Although the deposit is mined for uranium, vanadium has a higher average abundance in the ore. Thus, the geochemistry of vanadium in the orebody was studied to characterize ore-forming processes...
Genetic implications of regional and temporal trends in ore fluid geochemistry of Mississippi Valley-type deposits in the Ozark region
J.G. Viets, D. L. Leach
1990, Economic Geology (85) 842-861
Fluids extracted from aqueous fluid inclusions in epigenetic gangue and ore minerals record the migration of huge volumes of highly saline fluids throughout the stratigraphic section of the Ozark region. The extracted fluids share many similarities regionally, but there are significant temporal differences which define two geochemically distinct end-member ore-forming...
The magnetospheric disturbance ring current as a source for probing the deep earth electrical conductivity
W.H. Campbell
1990, Pure and Applied Geophysics PAGEOPH (134) 541-557
Two current rings have been observed in the equatorial plane of the earth at times of high geomagnetic activity. An eastward current exists between about 2 and 3.5 earth radii (Re) distant, and a larger, more variable companion current exists between about 4 and 9 Re. These current regions are...
Reconnaissance techniques for determining soil-gas radon concentrations: an example from Prince Georges County, Maryland
G.M. Reimer
1990, Geophysical Research Letters (17) 809-812
Preliminary field measurements of soil-gas radon (Rn) concentrations can provide an initial assessment of the Rn potential in any location and aid in designing a larger or more detailed sampling program. Radon reconnaissance requires some special considerations because a large area must be covered in a...
Discontinuities in the shallow Martian crust at Lunae, Syria, and Sinai Plana
P. A. Davis, M.P. Golombek
1990, Journal of Geophysical Research Solid Earth (95) 14231-14248
Detailed photoclinometric profiles across 125 erosional features and 141 grabens in the western equatorial region of Mars indicate the presence of three discontinuities within the shallow crust. Pits, troughs, and wall valleys (tributary canyons) within Noctis Labyrinthus and Valles Marineris and escarpments within the fretted terrain of Sacra Fossae and...
Fluid-inclusion technique for determining maximum temperature in calcite and its comparison to the vitrinite reflectance geothermometer
C.E. Barker, R.H. Goldstein
1990, Geology (18) 1003-1006
Theory, laboratory experiments, and empirical observation suggest that many aqueous fluid inclusions in calcite reequilibrate during overheating, and therefore some homogenization temperatures (Th) record a temperature close to the maximum reached by the rock. This characteristic suggests that aqueous fluid inclusions in calcite can be used to establish maximum temperature...
Radium distribution and indoor radon in the Pacific Northwest
J. S. Duval, J. K. Otton
1990, Geophysical Research Letters (17) 801-804
Aerial gamma-ray data were compiled to produce a map showing the distribution of radium (226Ra) in near-surface materials in the Pacific Northwest (Washington, Oregon, and Idaho, and parts of Montana, Wyoming, California, Nevada, and Utah). A comparison of measurements of indoor concentration levels of radon (222Rn)...
Seismic site effects and the spatial interpolation of earthquake seismograms: Results using aftershocks of the 1986 North Palm Springs, California, earthquake
P. Spudich, D.P. Miller
1990, Bulletin of the Seismological Society of America (80) 1504-1532
We address the following two questions. Can a microearthquake's ground motions be modeled by incident P and S waves that excite a site transfer-function that is a smooth function of incidence angle? Given recorded ground motions from a set of earthquakes having known locations and mechanisms, can we derive such...
Characterization of transport in an acidic and metal-rich mountain stream based on a lithium tracer injection and simulations of transient storage
Kenneth E. Bencala, Diane M. McKnight, Gary W. Zellweger
1990, Water Resources Research (26) 989-1000
Physical parameters characterizing solute transport in the Snake River (an acidic and metal-rich mountain stream near Montezuma, Colorado) were variable along a 5.2-km study reach. Stream cross-sectional area and volumetric inflow each varied by a factor of 3. Because of transient storage, the residence time of injected tracers in the...
36C1 measurements and the hydrology of an acid injection site
G. Vourvopoulos, J. V. Brahana, E. Nolte, G. Korschinek, A. Priller, B. Dockhorn
1990, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (52) 451-454
In an area in western Tennessee (United States), an industrial firm is injecting acidic (pH = 0.1) iron chloride into permeable zones of carbonate rocks at depths ranging from 1000 to 2200 m below land surface. Overlying the injection zone at a depth of approximately 500 m below land surface...
Magmatic unrest at Long Valley Caldera, California, 1980-1990
R. A. Bailey, D.P. Hill
1990, Geoscience Canada (17) 175-179
On May 25, 1980, the resort town of Mammoth Lakes, California, was shaken by a remarkable 48-hour-long earthquake sequence that included four M=6, two M=5 and 300 M=3 quakes. The nature of the precursory seismicity plus the unusual character of the May 25-27 sequence itself suggested that it was not...
The relation of catastrophic flooding of Mangala Valles, Mars, to faulting of Memnonia Fossae and Tharsis volcanism
K. L. Tanaka, M. G. Chapman
1990, Journal of Geophysical Research Solid Earth (95) 14315-14323
Detailed stratigraphic relations indicate two coeval periods of catastrophic flooding and Tharsis centered faulting (producing Memnonia Fossae) in the Mangala Valles region of Mars. Major sequences of lava flows of the Tharsis Montes Formation and local, lobate plains flows were erupted during and between these channeling and faulting episodes. First,...
Interpretation of Na-K-Mg relations in geothermal waters
R.O. Fournier
1990, Conference Paper, Transactions - Geothermal Resources Council
When using a Na-K-???Mg triangular diagram as an aid in the interpretation of a geothermal water, the estimated temperature of last water-rock equilibration may change by as much as 50??C, depending on which of the many Na/K geothermometers one assumes is correct. A particular geothermometer may work well in one...
Temperature, size, and depth of the magma reservoir for the Taylor Creek Rhyolite, New Mexico
W. A. Duffield, du Bray
1990, American Mineralogist (75) 1059-1070
The 55 km3 mid-Tertiary Taylor Creek Rhyolite in southwestern New Mexico consists of 20 lava domes and flows. This rhyolite is metaluminous to weakly peraluminous. Compositional zonation in feldspar phenocrysts is very minor and nonsystematic. The compositions of each feldspar species vary little throughout the suite of analyzed samples. This...
Coal and peat in the sub-Saharan region of Africa: alternative energy options?
Jean Noe Weaver, Edwin R. Landis
1990, Natural Resources Forum (14) 64-69
Increased energy demand as a result of growth in population, trends to sedentation and urbanization, and the desire for improvement in living standards, coupled with apparent climatic changes, are reducing fuelwood availability and contributing to deforestation and desertification in the sub‐Saharan countries. In 14 of those countries, the transport, industrial,...
Kilbuck terrane: Oldest known rocks in Alaska
S. E. Box, E. J. Moll-Stalcup, J. L. Wooden, J.Y. Bradshaw
1990, Geology (18) 1219-1222
The Kilbuck terrane in southwestern Alaska is a narrow, thin crustal sliver or flake of amphibolite facies orthogneiss. The igneous protolith of this gneiss was a suite of subduction-related platonic rocks. U-Pb data on zircons from trondhjemitic and granitic samples yield upper-intercept (igneous)...
Crustal structure of the northwestern Basin and Range Province from the 1986 Program for Array Seismic Studies of the Continental Lithosphere Seismic Experiment
Harley M. Benz, R. B. Smith, Walter D. Mooney
1990, Journal of Geophysical Research (95) 21823-21842
A portion of northwestern Nevada was imaged to determine the crustal structure and to assess reported differences between refraction versus reflection determinations of Moho depth and how the crustal composition and structure has been influenced by volcanic and extension mechanisms. Interpretation of the refraction/wide-angle reflection data suggests that the crust...
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....
The US Geological Survey's National Mapping Division programs, products, and services that can support wetlands mapping
F.S. Baxter
1990, Biological Report - US Fish & Wildlife Service (90) 87-92
The US Geological Survey (USGS) programs can play an important role in support of President Bush's policy of no net loss of wetlands. A principal goal of USGS is to provide cartographic information that contributes to the wise management of the Nation's natural resources. This information consists of maps, cartographic...
Trace element and isotopic constraints on magmatic evolution at Lassen volcanic center
T.D. Bullen, M.A. Clynne
1990, Journal of Geophysical Research Solid Earth (95) 19671-19691
Magmatic evolution at the Lassen volcanic center (LVC) is characterized by a transition from predominantly andesitic to predominantly silicic volcanism with time. Magmas of the andesitic, or “Brokeoff phase” of volcanism range in composition from basaltic andesite io dacite, whereas those of silicic, or “Lassen phase” range in composition from...
Particle velocity interpolation in block-centered finite difference groundwater flow models
Daniel J. Goode
1990, Water Resources Research (26) 925-940
A block-centered, finite difference model of two-dimensional groundwater flow yields velocity values at the midpoints of interfaces between adjacent blocks. Method of characteristics, random walk and particle-tracking models of solute transport require velocities at arbitrary particle locations within the finite difference grid. Particle path lines and travel times are sensitive...
Estimated post-Messinian sediment supply and sedimentation rates on the Ebro continental margin, Spain
C.H. Nelson
1990, Marine Geology (95) 395-418
Because of the extensive data base of seismic profiles, radiometric ages, and stratigraphic time markers such as the subaerial Messinian surface, sedimentation rates and Ebro River sediment discharge can be estimated for different periods and environments of the Ebro continental margin....
Operation of U.S. Geological Survey unmanned digital magnetic observatories
L.R. Wilson
1990, Physics of the Earth and Planetary Interiors (59) 45-54
The precision and continuity of data recorded by unmanned digital magnetic observatories depend on the type of data acquisition equipment used and operating procedures employed. Three generations of observatory systems used by the U.S. Geological Survey are described. A table listing the frequency of component failures in the current observatory...
Vapor-liquid phase equilibria of potassium chloride-water mixtures: Equation-of-state representation for KCl-H2O and NaCl-H2O
J.K. Hovey, Kenneth S. Pitzer, J.C. Tanger IV, J. L. Bischoff, R.J. Rosenbauer
1990, Journal of Physical Chemistry (94) 1175-1179
Measurements of isothermal vapor-liquid compositions for KCl-H2O as a function of pressure are reported. An equation of state, which was originally proposed by Pitzer and was improved and used by Tanger and Pitzer to fit the vapor-liquid coexistence surface for NaCl-H2O, has been used for representation of the KCl-H2O system...
Trace elements in Corbicula fluminea from the San Joaquin River, California
H.V. Leland, B. C. Scudder
1990, Conference Paper, Science of the Total Environment
(i) Trace element concentrations in soft tissue of the benthic bivalve, Corbicula fluminea, from the San Joaquin River and its major tributaries were examined during the primary irrigation season in relation to the spatial variation in concentrations of major, minor and trace constituents in riverwater and sediments. (ii) Selenium concentrations...
