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.
Filter Total Items: 5365
Comparability and accuracy of fluvial-sediment data - A view from the U.S. Geological Survey
The quality of historical fluvial-sediment data cannot be taken for granted, based on a review of upper Colorado River basin suspended-sediment discharges, and on an evaluation of the reliability of Total Suspended Solids (TSS) data. Additionally, the quality of future fluvial-sediment data are not assured. Sediment-surrogate technologies, including those that operate on acoustic, laser, bulk opti
Authors
J. R. Gray, G.D. Glysson, D. S. Mueller
Comparison of dialysis membrane diffusion samplers and two purging methods in bedrock wells
Collection of ground-water samples from bedrock wells using low-flow purging techniques is problematic because of the random spacing, variable hydraulic conductivity, and variable contamination of contributing fractures in each well's open interval. To test alternatives to this purging method, a field comparison of three ground-water-sampling techniques was conducted on wells in fractured bedrock
Authors
T.E. Imbrigiotta, T. A. Ehlke, P.J. Lacombe, J.M. Dale
Considerations for sampling inorganic constituents in ground water using diffusion samplers
Data indicate that nylon-screen and dialysis diffusion samplers are capable of obtaining concentrations of inorganic solutes in ground water from wells that closely correspond to concentrations obtained by low-flow sampling. Conservative solutes, such as chloride, can be sampled by filling the diffusion samplers with oxygenated water. The samplers should be filled with anaerobic water for sampling
Authors
D. A. Vroblesky, M.D. Petkewich, T.R. Campbell
Continuous monitoring of suspended sediment in rivers by use of optical backscatterance sensors
No abstract available.
Authors
D. H. Schoellhamer, S.A. Wright
Custom analysis; a winning proposition for customers and the National Laboratory
No abstract available.
Authors
Mark R. Burkhardt
Deep space 1 mission and observation of comet Borrellly
The NASA's new millennium program (NMP) focuses on testing high-risk, advanced technologies in space with low-cost flights. The objective of the NMP technology validation missions is to enable future science missions. The NMP missions are technology-driven, with the principal requirements coming from the needs of the advanced technologies that form the 'payload'.
Authors
M. Lee, R.J. Weidner, L. A. Soderblom
Determining the hydraulic properties of saturated, low-permeability geological materials in the laboratory: Advances in theory and practice
The accurate hydraulic characterization of low-permeability subsurface environments has important practical significance. In order to examine this issue from the perspective of laboratory-based approaches, we review some recent advancements in the theoretical analyses of three different laboratory techniques specifically applied to low-permeability geologic materials: constant-head, constant flow-
Authors
M. Zhang, M. Takahashi, R. H. Morin, H. Endo, T. Esaki
Development of a benthic macroinvertebrate index to assess biological integrity the Ohio River
No abstract available at this time
Authors
J.M. Applegate, P. C. Baumann, E.E. Emery
Discharge Measurements in Shallow Urban Streams Using a Hydroacoustic Current Meter
Hydroacoustic current-meter measurements were evaluated in small urban streams under a range of stages, velocities, and channel-bottom materials. Because flow in urban streams is often shallow, conventional mechanical current-meter measurements are difficult or impossible to make. The rotating-cup Price pygmy meter that is widely used by the U.S. Geological Survey and other agencies should not be
Authors
G. T. Fisher, S. E. Morlock
Dublin Histopathology Workshop. Parasites: Notes and images
No abstract available.
Effectiveness of Brucella abortus Strain 19 single calfhood vaccination in elk (Cervus elaphus)
Brucellosis in Greater Yellowstone Area (GYA) bison and elk has been a source of controversy and focus of the Greater Yellowstone Interagency Brucellosis Committee (GYIBC) for years. Brucellosis has been eradicated from cattle in the 3 states of Wyoming, Montana, and Idaho and all three states currently are classified as “brucellosis free” with regard to livestock. Yet free-ranging elk that attend
Authors
Thomas J. Roffe, Lee C. Jones, Kenneth Coffin, Steven J. Sweeney
Effects of anthropogenic fragmentation and livestock grazing on western riparian bird communities
Deciduous vegetation along streams and rivers provides breeding habitat to more bird species than any other plant community in the West, yet many riparian areas are heavily grazed by cattle and surrounded by increasingly developed landscapes. The combination of cattle grazing and landscape alteration (habitat loss and fragmentation) are thought to be critical factors affecting the richness and com
Authors
J.J. Tewksbury, A.E. Black, N. Nur, V.A. Saab, B.D. Logan, D.S. Dobkin