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Not all publications have extents, not all extents are completely accurate
Germanium geochemistry and mineralogy
L.R. Bernstein
1985, Geochimica et Cosmochimica Acta (49) 2409-2422
Germanium is enriched in the following geologic environments:1.(1) iron meteorites and terrestrial iron-nickel;2.(2) sulfide ore deposits, particularly those hosted by sedimentary rocks;3.(3) iron oxide deposits;4.(4) oxidized zones of Ge-bearing sulfide deposits;5.(5) pegmatites, greisens, and skarns; and6.(6) coal...
The impact of wave loads and pore-water pressure generation on initiation of sediment transport
E.C. Clukey, F.H. Kulhawy, P.L.-F. Liu, G. B. Tate
1985, Geo-Marine Letters (5) 177-183
The build-up of pore-water pressure by waves can lead to sediment liquefaction and subsequent transport by traction currents. This process was investigated by measuring pore-water pressures both in a field experiment and laboratory wave tank tests. Liquefaction was observed in the wave tank tests. The results suggest that sand is...
Sorting of bed load sediment by flow in meander bends
Gary Parker, E.D. Andrews
1985, Water Resources Research (21) 1361-1373
Equilibrium sorting of coarse mobile bed load sediment in meander bends is considered. A theory of two-dimensional bed load transport of graded material, including the effects of gravity on lateral slopes and secondary currents, is developed. This theory is coupled with a simple treatment of flow in bends, an analytically...
NEUTRALIZATION OF ACIDIC GROUND WATER NEAR GLOBE, ARIZONA.
James H. Eychaner, Kenneth G. Stollenwerk
Schmidt Kenneth D., editor(s)
1985, Conference Paper
Highly acidic contaminated water is moving through a shallow aquifer and interacting with streams near Globe, Arizona. Dissolved concentrations reach 3,000 mg/L iron, 150 mg/L copper, and 16,400 mg/L total dissloved solids; pH is as low as 3. 6. Samples from 16 PVC-cased observation wells include uncontaminated, contaminated, transition, and...
PRE-ORE POTASSIUM METASOMATISM, CREEDE MINING DISTRICT, COLORADO.
P. M. Bethke, R. O. Rye, P. B. Barton Jr.
1985, Conference Paper
Rhyolitic welded-tuff wallrocks of the epithermal base and precious metal veins of the Creede district were pervasively altered by the addition of more than two billion metric tons of potassium some 1. 5-2 million years before mineralization. Sodium, calcium and magnesium were strongly depleted, yielding a nearly binary quartz plus...
A comparative study of stream water and stream sediment as geochemical exploration media in the Rio Tanama porphyry copper district, Puerto Rico
R. E. Learned, T. T. Chao, R. F. Sanzolone
1985, Journal of Geochemical Exploration (24) 175-195
To test the relative effectiveness of stream water and sediment as geochemical exploration media in the Rio Tanama porphyry copper district of Puerto Rico, we collected and subsequently analyzed samples of water and sediment from 29 sites in the rivers and tributaries of the district. Copper, Mo, Pb, Zn, SO42−,...
Installation of observation wells on hazardous waste sites in Kansas using a hollow-stem auger
C. A. Perry, R. J. Hart
1985, Ground Water Monitoring and Remediation (5) 70-73
Noncontaminating procedures were used during the hollow-stem auger installation of 12 observation wells on three hazardous waste sites in Kansas. Special precautions were taken to ensure that water samples were representative of the ground water in the aquifer and were not subjected to contamination from the land surface or cross...
Seismic and geochemical evidence for shallow gas in sediment on Navarin continental margin, Bering Sea
Paul R. Carlson, Margaret Golan-Bac, Herman A. Karl, Keith A. Kvenvolden
1985, American Association of Petroleum Geologists Bulletin (69) 422-436
Marine seismic studies coupled with geochemical investigations demonstrate that hydrocarbon gases are ubiquitous in the near-surface (<= 250 m or 820 ft depth) sediment of the Navarin continental margin in the northern Bering Sea. Three types of acoustic anomalies appear to be related to the presence of gas in the...
MODELING HYDRAULIC PROBLEMS USING THE CVBEM AND THE MICROCOMPUTER.
Chintu Lai, T. V. Hromadka II
1985, Conference Paper
The Complex Variable Boundary Element Method (CVBEM) offers an effective and efficient means for modeling two-dimensional potential and related flow problems. The method has been applied to various hydraulic and hydrodynamic problems - surface water, ground water, and other flows - and has proven its accuracy, reliability and usefulness. The...
A two-dimensional dam-break flood plain model
T. V. Hromadka II, C. E. Berenbrock, J. R. Freckleton, G. L. Guymon
1985, Advances in Water Resources (8) 7-14
A simple two-dimensional dam-break model is developed for flood plain study purposes. Both a finite difference grid and an irregular triangle element integrated finite difference formulation are presented. The governing flow equations are approximately solved as a diffusion model coupled to the equation of continuity. Application of the model to...
Recent movement on the Garlock Fault as suggested by water level fluctuations in a well in Fremont Valley, California
Diane K. Lippincott, John D. Bredehoeft, W. R. Moyle Jr.
1985, Journal of Geophysical Research Solid Earth (90) 1911-1924
Water levels have been continuously recorded since March 1978 in a well in Fremont Valley, where several strands of the adjacent Garlock fault zone have exhibited both left-lateral displacement and components of normal displacement. Differences in water levels indicate that a fault segment lies between the observation well and a...
Effects of cumulative loading level, as fish weight per unit flow, on water quality and growth of lake trout
J. W. Meade, J.S. Ramsey, J.C. Williams
1985, Journal of the World Mariculture Society (16) 40-51
Lake trout, Salvelinus namaycush, were cultured in a series of five rearing units (in triplicate). The fish removed available oxygen in each unit, from about 10.5 to 7.0 mg/L. Oxygen was replaced, through aeration, between rearing units. Effects of cumulative loading, as fish weight/flow rate, are described in terms of water...
Lognormal field size distributions as a consequence of economic truncation
E. D. Attanasi, L.J. Drew
1985, Journal of the International Association for Mathematical Geology (17) 335-351
The assumption of lognormal (parent) field size distributions has for a long time been applied to resource appraisal and evaluation of exploration strategy by the petroleum industry. However, frequency distributions estimated with observed data and used to justify this hypotheses are conditional. Examination of various observed field size distributions across...
Mineral-water reactions in metamorphism and volcanism
I. Barnes
1985, Chemical Geology (49) 21-29
Low-temperature (120??C and less) metamorphism of graywacke, granite and andesite yields zeolites and precursor gels by reaction with fresh water but low-greenschist facies by reaction with salt (sea)water. ?? 1985....
Vp/Vs ratios in the Yellowstone National Park region, Wyoming
S.N. Chatterjee, A.D. Pitt, H. M. Iyer
1985, Journal of Volcanology and Geothermal Research (26) 213-230
In this paper we study the variation of Vp/Vs and Poisson's ratio (??) in the Yellowstone National Park region, using earthquakes which were well recorded by a local seismic network. We find that the average Vp/Vs value within the geothermally active Yellowstone caldera is about 7% lower than in the...
Determination of interstitial chloride in shales and consolidated rocks by a precision leaching technique
Frank T. Manheim, E.E. Peck, Candice M. Lane
1985, Society of Petroleum Engineers journal (25) 704-710
We have devised a technique for determining chloride in interstitial water of consolidated rocks. Samples of rocks ranging from 5 to 10 g are crushed and sieved under controlled conditions and then ground with distilled water to submicron size in a closed mechanical mill. After ultra-centrifugation, chloride content is determined...
An underwater instrument for determining bearing capacity of shallow marine sediments
Ronald C. Circe
1985, Geotechnical Testing Journal (8) 96-98
A small, portable, underwater instrument for measuring carbonate substrate bearing capacity in situ is described. The device was used in various shallow water (< 9 m) carbonate reef environments. Criteria for design and operation were based on ability to deliver controlled levels of stress to bearing plates of various sizes,...
Water-level changes in the Ogallala aquifer, northwestern Oklahoma.
J.S. Havens
1985, Oklahoma Geology Notes (45) 205-210
The Ogallala aquifer, that part of the High Plains aquifer in Oklahoma, is part of a regional aquifer system that underlies parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. In 1978 the US Geological Survey began a 5- year study of the High Plains regional...
Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota
J. R. Stark, M. F. Hult
1985, Water-Resources Investigations Report 85-4087
A three-dimensional, ground-water-flow model of the Prairie du Chien-Jordan aquifer and associated hydrogeologic units was developed to evaluate the movement of coal-tar derivatives from a coal-tar distillation and wood-preserving plant in St. Louis Park, Minnesota. A finite-difference grid was superimposed on the modeled area, which includes most of eastern Hennepin...
Persistence of an introduced mud flat community in south San Francisco Bay, California
Frederic H. Nichols, Janet K. Thompson
1985, Marine Ecology Progress Series (24) 83-97
The benthic invertebrate community inhabiting the extensive and sedimentologically homogeneous mudflats of South San Francisco Bay has demonstrated a high degree of constancy in both species composition and relative abundance among species throughout 10 yr of observation. The community, composed predominantly of introduced species with opportunistic lifestyles, is dominated numerically...
Land subsidence caused by ground water withdrawal in urban areas
T.L. Holzer, A.I. Johnson
1985, GeoJournal (11) 245-255
At least eight urban areas in the world have encountered significant economic impact from land subsidence caused by pumping of ground water from unconsolidated sediment. The areas, most of which are coastal, include Bangkok, Houston, Mexico City, Osaka, San Jose, Shanghai, Tokyo, and Venice. Flooding related to decreased ground elevation...
Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout
P. F. Woods
1985, Water-Resources Investigations Report 85-4292
The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area < 25 sq hectometers) lakes in the Matanuska-Susitna Borough. The project goal was to develop empirical models for predicting rainbow trout growth rates from the following variables: total...
Errors and parameter estimation in precipitation-runoff modeling: 2. Case study
Brent M. Troutman
1985, Water Resources Research (21) 1214-1222
A case study is presented which illustrates some of the error analysis, sensitivity analysis, and parameter estimation procedures reviewed in the first part of this paper. It is shown that those procedures, most of which come from statistical nonlinear regression theory, are invaluable in interpreting errors in precipitation-runoff modeling and...