Conference Papers
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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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Inversion of multichannel geophysical data with projected kernels Inversion of multichannel geophysical data with projected kernels
Statistical de‐noising methods such as Principal Component Analysis modify data in a way not constrained by physics. In much the same way as frequency‐filtered data must incorporate altered frequency content into numerical interpretation, so must statistically rotated data include the rotation operator in inversion processes. We propose a method of accounting for statistical reduction of...
Authors
M. Andy Kass, Trevor P. Irons, Yaoguo Li
Influence of Old World bluestem (Bothrichloa ischaemum) monocultures on breeding density of three grassland songbirds in Oklahoma Influence of Old World bluestem (Bothrichloa ischaemum) monocultures on breeding density of three grassland songbirds in Oklahoma
Despite persistent and widespread declines of grassland birds in North America, few studies have assessed differences between native grasslands and seeded monocultures as songbird habitat. In the Great Plains, many fields enrolled in the Conservation Reserve Program have been seeded to Old World bluestems (OWB), but there is evidence to suggest that OWB may not provide suitable...
Authors
Andrew D. George, Timothy J. O’Connell, Karen R. Hickman, David M. Leslie
Defining fish nursery habitats: An application of otolith elemental fingerprinting in Tampa Bay, Florida Defining fish nursery habitats: An application of otolith elemental fingerprinting in Tampa Bay, Florida
Fishing in Tampa Bay enhances the quality of life of the area's residents and visitors. However, people's desire to settle along the Bay's shorelines and tributaries has been detrimental to the very habitat believed to be crucial to prime target fishery species. Common snook (Centropomus undecimalis) and red drum (Sciaenops ocellatus) are part of the suite of estuarine fishes that 1) are
Authors
Janet A. Ley, Carole C. McIvor, Ernst B Peebles, Holly Rolls, Suzanne T. Cooper
Inference of distributional parameters from compositional samples containing nondetects Inference of distributional parameters from compositional samples containing nondetects
Low concentrations of elements in geochemical analyses have the peculiarity of being compositional data and, for a given level of significance, are likely to be beyond the capabilities of laboratories to distinguish between minute concentrations and complete absence, thus preventing laboratories from reporting extremely low concentrations of the analyte. Instead, what is reported is the...
Authors
Ricardo A. Olea
Quantifying the undiscovered geothermal resources of the United States Quantifying the undiscovered geothermal resources of the United States
In 2008, the U.S. Geological Survey (USGS) released summary results of an assessment of the electric power production potential from the moderate- and high-temperature geothermal resources of the United States (Williams et al., 2008a; USGS Fact Sheet 2008-3082; http://pubs.usgs.gov/fs/2008/3082). In the assessment, the estimated mean power production potential from undiscovered...
Authors
Colin F. Williams, Marshall J. Reed, Jacob DeAngelo, S. Peter Galanis
Analysis of complex pumping interactions during an aquifer test conducted at a well field in the coastal plain near Augusta, Georgia, October 2009 Analysis of complex pumping interactions during an aquifer test conducted at a well field in the coastal plain near Augusta, Georgia, October 2009
A 24-hour aquifer test was conducted in Well Field 2 near Augusta, Georgia, October 21–22, 2009, to characterize the hydraulic properties of the Midville aquifer system. The selected well was pumped at a rate of 684 gallons per minute. At the initiation of aquifer-test pumping, water levels in each of eight wells monitored for the test were still recovering from the well-field production...
Authors
Gerald J. Gonthier
Use of the U.S. Geological Survey StreamStats Web Application for dam safety analysis Use of the U.S. Geological Survey StreamStats Web Application for dam safety analysis
No abstract available.
Authors
John D. Guthrie, Kernell G. Ries, Peter A. Steeves
Temporal characteristics of coherent flow structures generated over alluvial sand dunes, Mississippi River, revealed by acoustic doppler current profiling and multibeam echo sounding Temporal characteristics of coherent flow structures generated over alluvial sand dunes, Mississippi River, revealed by acoustic doppler current profiling and multibeam echo sounding
This paper investigates the flow in the lee of a large sand dune located at the confluence of the Mississippi and Missouri Rivers, USA. Stationary profiles collected from an anchored boat using an acoustic Doppler current profiler (ADCP) were georeferenced with data from a real-time kinematic differential global positioning system. A multibeam echo sounder was used to map the bathymetry...
Authors
John A. Czuba, Kevin A. Oberg, Jim L. Best, Daniel R. Parsons, S. M. Simmons, K. K. Johnson, C. Malzone
Velocity mapping in the Lower Congo River: A first look at the unique bathymetry and hydrodynamics of Bulu Reach Velocity mapping in the Lower Congo River: A first look at the unique bathymetry and hydrodynamics of Bulu Reach
The lower Congo River is one of the deepest, most powerful, and most biologically diverse stretches of river on Earth. The river’s 270 m decent from Malebo Pool though the gorges of the Crystal Mountains to the Atlantic Ocean (498 km downstream) is riddled with rapids, cataracts, and deep pools. Much of the lower Congo is a mystery from a hydraulics perspective. However, this stretch of...
Authors
P. Ryan Jackson, Kevin A. Oberg, Ned Gardiner, John Shelton
A deployment of broadband seismic stations in two deep gold mines, South Africa A deployment of broadband seismic stations in two deep gold mines, South Africa
In-mine seismic networks throughout the TauTona and Mponeng gold mines provide precise locations and seismic source parameters of earthquakes. They also support small-scale experimental projects, including NELSAM (Natural Earthquake Laboratory in South African Mines), which is intended to record, at close hand, seismic rupture of a geologic fault that traverses the project region near...
Authors
Arthur F. McGarr, Margaret S. Boettcher, Jon Peter B. Fletcher, Malcolm J. S. Johnston, R. Durrheim, S. Spottiswoode, A. Milev
Composition and source of salinity of ore-bearing fluids in Cu-Au systems of the Carajás Mineral Province, Brazil Composition and source of salinity of ore-bearing fluids in Cu-Au systems of the Carajás Mineral Province, Brazil
The composition and Cl/Br – NaCl ratios of highly saline aqueous inclusions from large tonnage (> 100 t) IOCG deposits (Sossego, Alvo 118, and Igarapé Bahia) and a Paleoproterozoic intrusion-related Cu-Au-(Mo-W-Bi-Sn) deposit (Breves; 50 Mt)) in the Carajás Mineral Province have been analysed by LA-ICP-MS and ion chromatography. In both Cu-Au systems, brine inclusions are Ca-dominated (5...
Authors
Roberto Xavier, Brian Rusk, Poul Emsbo, Lena Monteiro
Geochemistry and geochronology of carbonate-hosted base metal deposits in the southern Brooks Range, Alaska: Temporal association with VMS deposits and metallogenic implications Geochemistry and geochronology of carbonate-hosted base metal deposits in the southern Brooks Range, Alaska: Temporal association with VMS deposits and metallogenic implications
The Brooks Range contains enormous accumulations of zinc and copper, either as VMS or sediment-hosted deposits. The Ruby Creek and Omar deposits are Cu-Co stratabound deposits associated with dolomitic breccias. Numerous volcanogenic Cu-Zn (+/-Ag, Au) deposits are situated ~20 km north of the Ruby Creek deposit. The carbonate-hosted deposits consist of chalcopyrite and bornite that fill...
Authors
Karen Kelly, John Slack, David Selby