Magnetic and gravity constraints on forearc upper crustal structure and composition, offshore northeast Japan
Carol A. Finn
1994, Journal of Geomagnetism & Geoelectricity (46) 423-441
Marine magnetic and gravity data from the northeast Japan forearc offer insight to the subsurface structure, density and magnetization from which geologic interpretations and tectonic reconstructions can be made. Positive marine magnetic anomalies, on-land geology, drill hole data, and 2-1/2-dimensional models reveal that Kitakami plutons and possibly their associated volcanic...
Seawater as the source of minor elements in black shales, phosphorites and other sedimentary rocks
D.Z. Piper
1994, Chemical Geology (114) 95-114
Many of the minor elements in seawater today have a concentration-depth profile similar to that of the biologically essential nutrients, NO-3 and PO3-4. They show a relative depletion in the photic zone and enrichment in the deep ocean. The difference between their surface- and deep-ocean values, normalized to the change...
Geometry of an outcrop-scale duplex in Devonian flysch, Maine
D. C. Bradley, L.M. Bradley
1994, Journal of Structural Geology (16) 371-380
We describe an outcrop-scale duplex consisting of 211 exposed repetitions of a single bed. The duplex marks an early Acadian (Middle Devonian) oblique thrust zone in the Lower Devonian flysch of northern Maine. Detailed mapping at a scale of 1:8 has...
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...
Modeling the effects of climate change on water resources - a review
G.H. Leavesley
1994, Climatic Change (28) 159-177
Hydrologic models provide a framework in which to conceptualize and investigate the relationships between climate and water resources. A review of current studies that assess the impacts of climate change using hydrologic models indicates a number of problem areas common to the variety of models applied. These problem areas include...
Statistical forecasting of repetitious dome failures during the waning eruption of Redoubt Volcano, Alaska, February-April 1990
R.A. Page, J.C. Lahr, B. A. Chouet, J.A. Power, C.D. Stephens
1994, Journal of Volcanology and Geothermal Research (62) 183-196
The waning phase of the 1989-1990 eruption of Redoubt Volcano in the Cook Inlet region of south-central Alaska comprised a quasi-regular pattern of repetitious dome growth and destruction that lasted from February 15 to late April 1990. The dome failures produced ash plumes hazardous to airline traffic. In response to...
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...
Model for dolomite formation in northwest Florida
C.R. Cooper, J.A. Tindall
1994, Journal of Hydrology (157) 367-391
Petrographic methods are used to examine the nature of the Floridan post-Oligocene unconformity and diagenetic responses in the associated carbonate units. The study addresses the depositional environment and the character of sediments associated with the unconformity, types and timing of diagenetic changes, and mode of dolomitization for the Suwannee Limestone...
Variations in rupture process with recurrence interval in a repeated small earthquake
J.E. Vidale, W.L. Ellsworth, A. Cole, Chris Marone
1994, Nature (368) 624-626
In theory and in laboratory experiments, friction on sliding surfaces such as rock, glass and metal increases with time since the previous episode of slip. This time dependence is a central pillar of the friction laws widely used to model earthquake phenomena. On natural faults, other properties, such as rupture...
Indicators of sewage contamination in sediments beneath a deep-ocean dump site off New York
Michael H. Bothner, H. Takada, I.T. Knight, R. T. Hill, B. Butman, J.W. Farrington, R.R. Colwell, J. F. Grassle
1994, Marine Environmental Research (38) 43-59
The world's largest discharge of municipal sewage sludge to surface waters of the deep sea has caused measurable changes in the concentration of sludge indicators in sea-floor sediments, in a spatial pattern which agrees with the predictions of a recent sludge deposition model. Silver, linear alkylbenzenes, coprostanol, and spores of...
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...
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...
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
Hydrothermal alteration in oceanic ridge volcanics: A detailed study at the Galapagos Fossil Hydrothermal Field
W.I. Ridley, M.R. Perfit, I.R. Josnasson, M.F. Smith
1994, Geochimica et Cosmochimica Acta (58) 2477-2494
The Galapagos Fossil Hydrothermal Field is composed of altered oceanic crust and extinct hydrothermal vents within the eastern Galapagos Rift between 85°49′W and 85°55′W. The discharge zone of the hydrothermal system is revealed along scarps, thus providing an opportunity to examine the uppermost mineralized, and highly altered interior parts of...
Simulation of gas phase transport of carbon-14 at Yucca Mountain, Nevada, USA
N. Lu, B. Ross
1994, Waste Management (14) 409-420
We have simulated gas phase transport of Carbon-14 at Yucca Mountain, Nevada. Three models were established to calculate travel time of Carbon-14 from the potential repository to the mountain surface: a geochemical model for retardation factors, a coupled gas-flow and heat transfer model for temperature and gas flow fields, and...
Sediment resuspension and bed armoring during high bottom stress events on the northern California inner continental shelf: Measurements and predictions
P.L. Wiberg, D.E. Drake, D.A. Cacchione
1994, Continental Shelf Research (14) 1191-1219
Geoprobe bottom tripods were deployed during the winter of 1990–1991 on the northern California inner continental shelf as part of the STRESS field experiment. Transmissometer measurements of light beam attenuation were made at two levels and current velocity was measured at...
Intraspecific variation in the response of Taxodium distichum seedlings to salinity
J. A. Allen, J. L. Chambers, D. McKinney
1994, Forest Ecology and Management (70) 203-214
Seedlings of 15 open-pollinated families of baldcypress (Taxodium distichum) were tested for their tolerance to combined salinty and flooding stress. Ten of the families were from coastal locations in Louisiana or Alabama, USA, that were slightly brackish. The other families were from locations not affected by saltwater intrusion. Five salinity...
Descriptive and grade-tonnage models of Archean low-sulfide Au-quartz veins and a revised grade-tonnage model of Homestake Au
T. L. Klein, W. C. Day
1994, Open-File Report 94-250
Simulating effects of highway embankments on estuarine circulation
Jonathan K. Lee, Raymond W. Schaffranek, Robert A. Baltzer
1994, Journal of Waterway, Port, Coastal and Ocean Engineering (120) 199-218
A two‐dimensional, depth‐averaged, finite‐difference, numerical model was used to simulate tidal circulation and mass transport in the Port Royal Sound, South Carolina, estuarine system. The purpose of the study was to demonstrate the utility of the Surface‐Water, Integrated, Flow and Transport model (SWIFT2D) for evaluating changes in circulation patterns and...
Maps summarizing geohydrologic information in an area of salt-water disposal, eastern Altamont-Bluebell petroleum field, Uinta Basin, Utah
Geoffrey W. Freethey
1994, Water-Resources Investigations Report 92-4043
In the Altamont-Bluebell Petroleum Field within the Uinta Basin of Utah, saline oil-production water is being injected into the Duchesne River Formation. On the basis of geohydrologic information, a qualitative assessment of the possible effects of this injection indicates that fresh groundwater in certain areas of the Duchesne River formation...
Documentation of a computer program to simulate transient leakage from confining units using the modular finite-difference, ground-water flow model
S. A. Leake, P.P. Leahy, A. S. Navoy
1994, Open-File Report 94-59
Transient leakage into or out of a compressible fine-grained confining unit results from ground- water storage changes within the unit. The computer program described in this report provides a new method of simulating transient leakage using the U.S. Geological Survey modular finite- difference ground-water flow model (MODFLOW). The new...
Direct chemical analysis of uv laser ablation products of organic polymers by using selective ion monitoring mode in gas chromatography/mass-spectrometry
Yirang Cho, H.W. Lee, S.T. Fountain, D.M. Lubman
1994, Journal of the American Society for Mass Spectrometry (5) 106-112
Trace quantities of laser ablated organic polymers were analyzed by using commercial capillary column gas chromatography/mass spectrometry; the instrument was modified so that the iaser ablation products could be introduced into the capillary column directly and the constituents of each peak in the chromatogram were identified by using a mass...
Ionic strength and DOC determinations from various freshwater sources to the San Francisco Bay
Y.R. Hunter, J.S. Kuwabara
1994, Bulletin of Environmental Contamination and Toxicology (52) 311-318
An exact estimation of dissolved organic carbon (DOC) within the salinity gradient of zinc and copper metals is significant in understanding the limit to which DOC could influence metal speciation. A low-temperature persulfate/oxygen/ultraviolet wet oxidation procedure was utilized for analyzing DOC samples adapted for ionic strength from major freshwater sources...
Modes of occurrence of potentially hazardous elements in coal: Levels of confidence
Robert B. Finkelman
1994, Fuel Processing Technology (39) 21-34
The modes of occurrence of the potentially hazardous elements in coal will be of significance in any attempt to reduce their mobilization due to coal combustion. Antimony and selenium may be present in solid solution in pyrite, as minute accessory sulfides dispersed throughout the organic matrix, or in organic association....
Build your own low-cost seismic/bathymetric recorder annotator
W. Robinson
1994, Marine Geology (118) 1-3
An inexpensive programmable annotator, completely compatible with at least three models of widely used graphic recorders (Raytheon LSR-1811, Raytheon LSR-1807 M, and EDO 550) has been developed to automatically write event marks and print up to sixteen numbers on the paper record....
