Conference Papers
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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
Source of atrazine and desethylatrazine in a river, during base flow
A budget of atrazine and desethylatrazine loads was computed for a 116-kilometer reach of the Cedar River in Iowa to determine where these compounds enter the river during base-flow conditions. Loads were determined by measuring discharge and concentrations of the compounds for four main-stem sites along the Cedar River and for 27 tributaries on September 20-22, 1989. Tributaries contributed 17 pe
Authors
Paul J. Squillace, E. Michael Thurman, Edward E. Fischer, Phil J. Soenksen
Spatial Data Transfer Standard and efforts to develop a federal Profile for Vector Data
The ongoing efforts to create a more accessible and user friendly Spatial Data Transfer Standard include the development of a Profile for Vector Data and the development of a library of public domain software tools to support the encoding and decoding process. A profile is, in effect, a limited subset of the standard. The best way to use the standard is to first define a profile containing a limit
Authors
Matthew H. McDermott, Anthony DeWitt
Strontium isotopes in carbonate deposits at Crater Flat, Nevada
Strontium isotope studies of carbonates from soils, veins, eolian dust and Paleozoic basement sampled near Crater Flat, southwest of Yucca Mountain, provide evidence for the origins of these materials. Vein and soil carbonates have nearly identical ranges of 87Sr/86Sr, and eolian material has 87Sr/86Sr ratios at the lower end of the pedogenic range. The average 87Sr/86Sr of Paleozoic basement from
Authors
B.D. Marshall, K. Futa, Z. E. Peterman, J. S. Stuckless
Survey of rural, private wells. Statistical design
Half of Illinois' 38 million acres were planted in corn and soybeans in 1988. On the 19 million acres planted in corn and soybeans, approximately 1 million tons of nitrogen fertilizer and 50 million pounds of pesticides were applied. Because groundwater is the water supply for over 90 percent of rural Illinois, the occurrence of agricultural chemicals in groundwater in Illinois is of interest to t
Authors
Edward Mehnert, Susan C. Schock
Techniques and strategies for data integration in mineral resource assessment
The Geologic and the National Mapping divisions of the U.S. Geological Survey have been involved formally in cooperative research and development of computer-based geographic information systems (GISs) applied to mineral-resource assessment objectives since 1982. Experience in the Conterminous United States Mineral Assessment Program (CUSMAP) projects including the Rolla, Missouri; Dillon, Montana
Authors
Charles M. Trautwein, John L. Dwyer
Testing a method-of-characteristics model of three-dimensional solute transport in ground water
A new three-dimensional model of solute transport in groundwater that is based on a widely used two-dimensional method of characteristics model and is coupled to a modular finite-difference flow model is under development. The model's accuracy for ideal aquifers having homogeneous properties, uniform boundary conditions, and steady flow along a grid direction is demonstrated by comparison with con
Authors
Daniel J. Goode, Leonard F. Konikow
The application of current techniques in molecular biology for detection and control of infectious diseases in salmonid aquaculture
No abstract available
Authors
A.C. Fox, C.K. Arakawa, J. R. Winton