Integrated geology and preliminary cross section along the north ramp of the Exploratory Studies Facility, Yucca Mountain
D.C. Buesch, R. P. Dickerson, R.M. Drake, R.W. Spengler
1994, Conference Paper, High Level Radioactive Waste Management - Proceedings of the Annual International Conference
The Exploratory Studies Facility is a major part of the site characterization activities at Yucca Mountain, Nevada, and the north ramp is the first phase of construction. The N61W trending north ramp will transect the Bow Ridge and Drill Hole Wash faults and numerous minor faults, and traverses two thick...
Karstification without carbonic acid: Bedrock dissolution by gypsum- driven dedolomitization
J. L. Bischoff, R. Julia, Wayne C. Shanks, R.J. Rosenbauer
1994, Geology (22) 995-998
Aggressive karstification can take place where dolomite and gypsum are in contact with the same aquifer. Gypsum dissolution drives the precipitation of calcite, thus consuming carbonate ions released by dolomite. Lake Banyoles, in northeastern Spain, is a karst lake supplied by sublacustrine springs,...
Fluid chemistry evolution and mineral deposition in the main-stage Creede epithermal system
G.S. Plumlee
1994, Economic Geology (89) 1860-1882
This paper presents results of chemical speciation and reaction path calculations that model fluid chemistry evolution and ore deposition in the main-stage Creede, Colorado, epithermal system. An extensive geologic, mineralogic, and geochemical framework for mineralization has been developed by many researchers for the central and southern district vein systems (OH...
Chemical reaction path modeling of ore deposition in Mississippi Valley-type Pb-Zn deposits of the Ozark region, US midcontinent
G.S. Plumlee, D. L. Leach, A. H. Hofstra, G. P. Landis, E. L. Rowan, J.G. Viets
1994, Economic Geology (89) 1361-1383
The Ozark region of the U.S. midcontinent is host to a number of Mississippi Valley-type districts, including the world-class Viburnum Trend, Old Lead Belt, and Tri-State districts and the smaller Southeast Missouri barite, Northern Arkansas, and Central Missouri districts. There is increasing evidence that the Ozark Mississippi Valley-type districts formed...
Deglaciation, lake levels, and meltwater discharge in the Lake Michigan basin
Steven M. Colman, J.A. Clark, L. Clayton, A.K. Hansel, C.E. Larsen
1994, Quaternary Science Reviews (13) 879-890
The deglacial history of the Lake Michigan basin, including discharge and routing of meltwater, is complex because of the interaction among (1) glacial retreats and re-advances in the basin (2) the timing of occupation and the isostatic adjustment of lake outlets and (3) the depositional and erosional processes that left...
Tectonics and geology of spreading ridge subduction at the Chile Triple Junction: a synthesis of results from Leg 141 of the Ocean Drilling Program
J.H. Behrmann, S.D. Lewis, S.C. Cande
1994, Geologische Rundschau (83) 832-852
An active oceanic spreading ridge is being subducted beneath the South American continent at the Chile Triple Junction. This process has played a major part in the evolution of most of the continental margins that border the Pacific Ocean basin. A combination of high resolution swath bathymetric maps, seismic reflection...
Suspended sediments of the modern Amazon and Orinoco rivers
R.H. Meade
1994, Quaternary International (21) 29-39
The Amazon and Orinoco Rivers are massive transcontinental conveyance systems for suspended sediment. They derive about 90% of their sediment from the Andes that support their western headwaters, transport it for thousands of kilometers across the breadth of the continent and deposit it in the coastal zones of the Atlantic....
Climate, interseasonal storage of soil water, and the annual water balance
P. C. D. Milly
1994, Advances in Water Resources (17) 19-24
The effects of annual totals and seasonal variations of precipitation and potential evaporation on the annual water balance are explored. It is assumed that the only other factor of significance to annual water balance is a simple process of water storage, and that the relevant storage capacity is the plant-available...
Relationship between the Porco, Bolivia, Ag-Zn-Pb-Sn deposit and the Porco Caldera
Charles G. Cunningham, Hugo Aparicio N., Fernando Murillo S., Nestor C. Jimenez, J. L. Lizeca B., Edwin H. McKee, George E. Ericksen, Franz Tavera V.
1994, Economic Geology (89) 1833-1841
The Porco Ag-Zn-Pb-Sn deposit, a major Ag producer in the 16th century and currently the major Zn producer in Bolivia, consists of a swarm of fissure-filling veins in the newly recognized Porco caldera. The caldera measures 5 km north-south by 3 km east-west and formed in response to the eruption...
Hydraulics and sediment transport processes in a pool-riffle rocky mountain stream
Douglas M. Thompson
1994, Conference Paper, Proceedings - National Conference on Hydraulic Engineering
Sediment transport processes related to varying channel-bed morphology were investigated from April to November, 1993 along a 1 km pool-riffle and step-pool reach of North Saint Vrain Creek, a small mountain stream in the Northern Colorado Rocky Mountains. Three hundred sixteen 16-256 mm tracer particles placed in two separate pool-riffle-pool...
Block versus continuum deformation in the Western United States
G. King, D. Oppenheimer, F. Amelung
1994, Earth and Planetary Science Letters (128) 55-64
The relative role of block versus continuum deformation of continental lithosphere is a current subject of debate. Continuous deformation is suggested by distributed seismicity at continental plate margins and by cumulative seismic moment sums which yield slip estimates that are less than estimates from plate motion studies. In contrast, block...
Effects of polar and nonpolar groups on the solubility of organic compounds in soil organic matter
C. T. Chiou, D. E. Kile
1994, Environmental Science & Technology (28) 1139-1144
Vapor sorption capacities on a high-organic-content peat, a model for soil organic matter (SOM), were determined at room temperature for the following liquids: n-hexane, 1,4-dioxane, nitroethane, acetone, acetonitrile, 1-propanol, ethanol, and methanol. The linear organic vapor sorption is in keeping with the dominance of vapor partition in peat SOM. These...
Palynology, paleoclimatology and correlation of middle Miocene beds from Porcupine River (locality 90-1), Alaska
J. M. White, T. A. Ager
1994, Quaternary International (22-23) 43-77
Beds in the Upper Ramparts Canyon of the Porcupine River, Alaska (67?? 20' N, 141?? 20' W), yielded a flora rich in pollen of hardwood genera now found in the temperate climates of North America and Asia. The beds are overlain or enclosed by two basalt flows which were dated...
Six years of change in Lake Nyos, Cameroon, yield clues to the past and cautions for the future
William C. Evans, L. D. White, M. L. Tuttle, G.W. Kling, G. Tanyileke, R. L. Michel
1994, Geochemical Journal (28) 139-162
The catastrophic release of gas from Lake Nyos, Cameroon, in 1986 caused substantial but incomplete mixing of the stratified water column. The post-release evolution of water-column structure has been monitored through April 1992. Changes began immediately after the event as rainfall and inflow brought dilute fluid into the surface layer....
Measurement of saturated hydraulic conductivity in fine-grained glacial tills in Iowa: Comparison of in situ and laboratory methods
D. Roger Bruner, Alan J. Lutenegger
1994, Conference Paper, ASTM Special Technical Publication
Nested-standpipe and vibrating-wire piezometers were installed in Pre-Illinoian Wolf Creek and Albernett formations at the Eastern Iowa Till Hydrology Site located in Linn County, Iowa. These surficial deposits are composed of fine-grained glacial diamicton (till) with occasional discontinuous lenses of sand and silt. They overlie the Silurian (dolomite) aquifer which...
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...
Seismic hazards at Kilauea and Mauna Loa volcanoes, Hawaii
F. W. Klein
1994, Open-File Report 94-216
A significant seismic hazard exists in south Hawaii from large tectonic earthquakes that can reach magnitude 8 and intensity XII. This paper quantifies the hazard by estimating the horizontal peak ground acceleration (PGA) in south Hawaii which occurs with a 90% probability of not being exceeded during exposure times from...
Grade and tonnage model of tungsten skarn deposits, Nevada
David A. John, James D. Bliss
1994, Open-File Report 94-5
No abstract available....
Codicil to the geophysical expression of selected mineral deposit models
W. D. Heran, editor(s)
1994, Open-File Report 94-174
The Northridge, California, earthquake of January 1994; a computer animation and paper model
T. R. Alpha, R.S. Stein
1994, Open-File Report 94-214-A
Hydrogeology and potential effects of changes in water use, Carson Desert agricultural area, Churchill County, Nevada
Douglas K. Maurer, Ann K. Johnson, Alan H. Welch
1994, Open-File Report 93-463
Operating Criteria and Procedures established in 1988 for delivery of water for irrigation in the Newlands Project area include regulations and methods to increase Project efficiency. Public Law 101-618 of 1990 includes a target of 75-percent Project efficiency and a program of water-rights acquisition for wetlands maintenance. The directives could...
Documentation of Model Input and Output Values Used for Analyses of Simulated Development in Stagecoac Valley, Lyon and Storey Counties, Western Nevada
Anne E. Carey
1994, Open-File Report 92-630
A previously published Geological Survey report (Professional Paper 1409-H) describes ground-water flow and simulated development scenarios in Stagecoach Valley, Lyon and Storey Counties, Nevada. This study was done as part of the Survey's Great Basin Regional Aquifer-Systems Analysis program. Documentation of model input and output values used for analysis of...
Mineral-resource assessments in Alaska; background information to accompany maps and reports about the geology and undiscovered-mineral-resource potential of the Mount Katmai Quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska Peninsula
J.R. Riehle, S. E. Church, R. L. Detterman, J. W. Miller
1994, Circular 1106
Geologic and geochemical field studies were carded out from 1983 to 1987 in the Mount Katmai l?x2 ? quadrangle and adjoining region, at the northeast end of the Alaska Peninsula. The region is nearly entirely within Katmai National Park and Preserve and has had almost no mineral production, so prior...
Modal analyses of selected Tertiary volcanic rocks from Nye and Lincoln counties, Nevada
W. R. Page, G. L. Dixon
1994, Open-File Report 94-151
Documentation of model input and output values for the simulation of the ground-water flow system and proposed withdrawals in the northern part of Vekol Valley, Arizona
K.J. Hollett
1994, Open-File Report 94-64
