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: 5321
Proposed U.S. Geological Survey standard for digital orthophotos
The U.S. Geological Survey has added the new category of digital orthophotos to the National Digital Cartographic Data Base. This differentially rectified digital image product enables users to take advantage of the properties of current photoimagery as a source of geographic information. The product and accompanying standard were implemented in spring 1991. The digital orthophotos will be quadran
Authors
David Hooper, Vincent Caruso
Recent advances in halibut (Hippoglossus spp.) culture
No abstract available
Authors
R.R. Stickney, H. W. Liu, S.D. Smith
Rehabilitation of a Species: The Black-Footed Ferret (Mustela nigripes)
Black-footed ferrets (Mustela nigripes) are an endangered carnivore endemic to North America. This small nocturnal member of the weasel family is totally dependent on the prairie dog (Cynomys spp.) ecosystem for survival. The ferret lives in prairie dog burrows and relies on prairie dogs for 90 percent of its diet (3,21). Poisoning of prairie dogs was largely responsible for the 98 percent redu
Authors
Brian Miller, Dean E. Biggins, Lou Hanebury, Courtney Conway, Chris Wemmer
Relation between the national handbook of recommended methods for water data acquisition and ASTM standards
In the late 1950's, intense demands for water and growing concerns about declines in the quality of water generated the need for more water-resources data. About thirty Federal agencies, hundreds of State, county and local agencies, and many private organizations had been collecting water data. However, because of differences in procedures and equipment, many of the data bases were incompatible. I
Authors
G. Douglas Glysson, John V. Skinner
Relationship between weathered coal deposits and the etiology of Balkan endemic nephropathy
Field studies in epidemiology and environmental geochemistry in areas in Yugoslavia containing villages with a high incidence of Balkan endemic nephropathy (BEN), indicate a possible relationship between the presence of low-rank coal deposits and the etiology of BEN. Preliminary results from qualitative chemical analyses of drinking water from shallow farm wells indicate the presence of soluble po
Authors
G. L. Feder, Z. Radovanovic, R. B. Finkelman
Role of sediment-trace element chemistry in water-quality monitoring and the need for standard analytical methods
Multiple linear regression models calculated from readily obtainable chemical and physical parameters can explain a high percentage (70% or greater) of observed sediment trace-element variance for Cu, Zn, Pb, Cr, Ni, Co, As, Sb, Se, and Hg. Almost all the factors used in the various models fall into the category of operational definitions (e.g., grain size, surface area, and geochemical substrates
Authors
Arthur J. Horowitz
Satellite and earth science data management activities at the U.S. geological survey's EROS data center
The U.S. Geological Survey's Earth Resources Observation Systems (EROS) Data Center, the national archive for Landsat data, has 20 years of experience in acquiring, archiving, processing, and distributing Landsat and earth science data. The Center is expanding its satellite and earth science data management activities to support the U.S. Global Change Research Program and the National Aeronautics
Authors
David M. Carneggie, Gary G. Metz, William C. Draeger, Ralph J. Thompson
Sensitivity analysis of a ground-water-flow model
A sensitivity analysis was performed on 18 hydrological factors affecting steady-state groundwater flow in the Upper Floridan aquifer near Albany, southwestern Georgia. Computations were based on a calibrated, two-dimensional, finite-element digital model of the stream-aquifer system and the corresponding data inputs. Flow-system sensitivity was analyzed by computing water-level residuals obtained
Authors
Lynn J. Torak
Sequence homologies between the N genes of the 07-71 and makah isolates of viral hemorrhagic septicemia virus
No abstract available
Authors
J. Bernard, M. Bremont, J. R. Winton
Simulation of vertical compaction in models of regional ground-water flow
A new computer program was developed to simulate vertical compaction in models of regional ground-water flow. The program accounts for ground-water storage changes and compaction in discontinuous interbeds or in extensive confining beds. The new program is a package for the U.S. Geological Survey modular finite-difference ground-water flow model. Several features of the program make it useful for
Authors
S. A. Leake
Solution of the one-dimensional consolidation theory equation with a pseudospectral method
The one-dimensional consolidation theory equation is solved for an aquifer system using a pseudospectral method. The spatial derivatives are computed using Fast Fourier Transforms and the time derivative is solved using a fourth-order Runge-Kutta scheme. The computer model calculates compaction based on the void ratio changes accumulated during the simulated periods of time. Compactions and expans
Authors
N. Sepulveda
Some current themes in physical hydrology of the land-atmosphere interface
Certain themes arise repeatedly in current literature dealing with the physical hydrology of the interface between the atmosphere and the continents. Papers contributed to the 1991 International Association of Hydrological Sciences Symposium on Hydrological Interactions between Atmosphere, Soil and Vegetation echo these themes, which are discussed in this paper. The land-atmosphere interface is th
Authors
P. C. D. Milly