Conference Papers
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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Graphic summary of gas hydrate occurrence by proxy measurements across the Blake Ridge, Sites 994, 995, and 997
[No abstract available]
Authors
T.D. Lorenson
Ground penetrating radar imaging of cap rock, caliche and carbonate strata
Field experiments show ground penetrating radar (GPR) can be used to image shallow carbonate stratigraphy effectively in a variety of settings. In south Florida, the position and structure of cap rock cover on limestone can be an important control on surface water flow and vegetation, but larger scale outcrops (tens of meters) of cap rock are sparse. GPR mapping through south Florida prairie, cypr
Authors
S.E. Kruse, J.C. Schneider, D.J. Campagna, J.A. Inman, T.D. Hickey
Ground-penetrating radar methods used in surface-water discharge measurements
The U.S. Geological Survey (USGS) operates a network of about 7,000 streamflow-gaging stations that monitor open-channel water discharge at locations throughout the United States. The expense, technical difficulties, and concern for the safety of operational personnel under some field conditions have led to the search for alternate measurement methods. Ground- penetrating radar (GPR) has been used
Authors
F. P. Haeni, Marc L. Buursink, John E. Costa, Nick B. Melcher, Ralph T. Cheng, William J. Plant
Guidelines for model calibration and application to flow simulation in the Death Valley regional groundwater system
Fourteen guidelines are described which are intended to produce calibrated groundwater models likely to represent the associated real systems more accurately than typically used methods. The 14 guidelines are discussed in the context of the calibration of a regional groundwater flow model of the Death Valley region in the southwestern United States. This groundwater flow system contains two sites
Authors
M. C. Hill, F. A. D'Agnese, C.C. Faunt
Habitat conservation and creation: Invoking the flood-pulse concept to enhance fisheries in the lower Mississippi River
Analysis of four years of growth data failed to identify a single temperature or hydrologic variable that consistently accounted for variation in annual growth of catfishes (Ictaluridae). Instead, a composite variable that measured duration of floodplain inundation when water temperature exceeded minima for active feeding was directly related to growth. Results indicated that floodplain inundation
Authors
H.L. Schramm, M.A. Eggleton, R.M. Mayo
Herbicides and herbicide degradates in shallow groundwater and the Cedar River near a municipal well field, Cedar Rapids, Iowa
Water samples were collected near a Cedar Rapids, Iowa municipal well field from June 1998 to August 1998 and analyzed for selected triazine and acetanilide herbicides and degradates. The purpose of the study was to evaluate the occurrence of herbicides and herbicide degradates in the well field during a period following springtime application of herbicides to upstream cropland. The well field is
Authors
R.A. Boyd
Hydrological Aspects of Weather Prediction and Flood Warnings: Report of the Ninth Prospectus Development Team of the U.S. Weather Research Program
Among the many natural disasters that disrupt human and industrial activity in the United States each year, including tornadoes, hurricanes, extreme temperatures, and lightning, floods are among the most devastating and rank second in the loss of life. Indeed, the societal impact of floods has increased during the past few years and shows no sign of abating. Although the scientific questions assoc
Authors
K.K. Droegemeier, J.D. Smith, S. Businger, C. Doswell, J. Doyle, C. Duffy, E. Foufoula-Georgiou, T. Graziano, L.D. James, V. Krajewski, M. LeMone, D. Lettenmaier, C. Mass, R. Pielke, P. Ray, S. Rutledge, J. Schaake, E. Zipser
Hydrothermal diamond anvil cell for XAFS studies of first-row transition elements in aqueous solutions up to supercritical conditions
A hydrothermal diamond anvil cell (HDAC) has been modified by drilling holes with a laser to within 150 ??m of the anvil face to minimize the loss of X-rays due to absorption and scatter by diamond. This modification enables acquisition of K-edge X-ray absorption fine structure (XAFS) spectra from first-row transition metal ions in aqueous solutions at temperatures ranging from 25??C to 660??C and
Authors
William A. Bassett, Alan J. Anderson, Robert A. Mayanovic, I.-Ming Chou
Identifying the usage patterns of methyl tert-butyl ether (MTBE) and other oxygenates in gasoline using gasoline surveys
Data on the volumes of oxygenates and other compounds in gasoline are available from several sources collectively referred as gasoline surveys. The gasoline surveys provide the most definitive knowledge of which oxygenate, if any, and what volumes of that oxygenate are being used in various areas of the country. This information is important in water-quality assessments for relating the detection
Authors
M.J. Moran, R.M. Clawges, J.S. Zogorski
Imaging and modeling new VETEM data
In previously reported work (Wright and others, 2000) we found that the very early time electromagnetic (VETEM) prototype system produced data from which high resolution images of a buried former foundry site at the Denver Federal Center were made. The soil covering the site is about 30 mS/m conductivity, and is thus relatively unfavorable for ground penetrating radar (GPR) imaging. We have survey
Authors
David L. Wright, David V. Smith, Jared D. Abraham, Raymond S. Hutton, E. Kent Bond, Tie Jun Cui, Alaeddin A. Aydiner, Weng Cho Chew
Interactive 3-D visualization: A tool for seafloor navigation, exploration and engineering
Recent years have seen remarkable advances in sonar technology, positioning capabilities, and computer processing power that have revolutionized the way we image the seafloor. The massive amounts of data produced by these systems present many challenges but also offer tremendous opportunities in terms of visualization and analysis. The authors have developed a suite of interactive 3D visualization
Authors
L. A. Mayer, M. Paton, L. Gee, S. V. Gardner, C. Ware
Laboratory measurements of compressional and shear wave speeds through methane hydrate
Simultaneous measurements of compressional and shear wave speeds through polycrystalline methane hydrate have been made. Methane hydrate, grown directly in a wave speed measurement chamber, was uniaxially compacted to a final porosity below 2%. At 277 K, the compacted material had a compressional wave speed of 3650 ?? 50 m/s. The shear wave speed, measured simultaneously, was 1890 ?? 30 m/s. From
Authors
W.F. Waite, M.B. Helgerud, A. Nur, J.C. Pinkston, L.A. Stern, S. H. Kirby, W. B. Durham