Applications of hydrologic information automatically extracted from digital elevation models
Susan K. Jenson
1991, Hydrological Processes (5) 31-44
Digital elevation models (DEMs) can be used to derive a wealth of information about the morphology of a land surface. Traditional raster analysis methods can be used to derive slope, aspect, and shaded relief information; recently-developed computer programs can be used to delineate depressions, overland flow paths, and watershed boundaries....
Radon-222 and its parent radionuclides in groundwater from two study areas in New Jersey and Maryland, U.S.A.
R. B. Wanty, S. L. Johnson, Paul H. Briggs
1991, Applied Geochemistry (6) 305-318
A study of groundwater chemistry and radionuclide mobility in New Jersey and Maryland was conducted to investigate natural processes that control the mobility of radionuclides in the water-rock system. Groundwater was sampled from two geological units in New Jersey and from six in Maryland. The water sampled was from aquifiers...
In situ bacterial selenate reduction in the agricultural drainage systems of western Nevada
R.S. Oremland, N.A. Steinberg, T. S. Presser, L.G. Miller
1991, Applied and Environmental Microbiology (57) 615-617
Dissimilatory in situ selenate reduction to elemental selenium in sediments from irrigated agricultural drainage regions of western Nevada was measured at ambient Se oxyanion concentrations. Selenate reduction was rapid, with turnover rate constants ranging from 0.04 to 1.8 h-1 at total Se concentrations in pore water of 13 to 455...
Herbicides in streams. Midwestern United States
Donald A. Goolsby, E. Michael Thurman, Dana W. Kolpin
1991, Conference Paper
Results from a 2-year study of 149 streams geographically distributed across the corn-producing region of 10 midwestern States show that detectable concentrations of herbicides persist year round in most streams. Some herbicides exceeded proposed maximum contaminant levels for drinking water for periods of several weeks to several months following application....
Fate of acetone in an outdoor model stream with a nitrate supplement, southern Mississippi, U.S.A.
R. E. Rathbun, D. W. Stephens, D. Y. Tai
1991, Journal of Hydrology (123) 225-242
The fate of acetone in an outdoor model stream to which nitrate was added as a nutrient supplement was determined. The stream, in southern Mississippi, U.S.A. was 234 m long. Water was supplied to the stream by an artesian well at about 1.21 s−1, resulting in a mean water velocity...
Temporal trends in fluvial-sediment discharge in Ohio, 1950-1987
S. M. Hindall
1991, Journal of Soil and Water Conservation (46) 311-313
Long-term fluvial-sediment records of annual suspended-sediment discharge data are available for eight daily suspended-sediment stations operated in Ohio. Graphical and statistical analyses of long-term sediment records indicate that, in general, no long-term (>3- to 5-year) trends are readily apparent in the relation between annual mean suspended-sediment discharge and water discharge...
Testing a method-of-characteristics model of three-dimensional solute transport in ground water
Daniel J. Goode, Leonard F. Konikow
Lennon Gerard P.Rouhani Shahrokh, editor(s)
1991, Conference Paper, Symposium on 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...
Geology of the platanares geothermal area, Departamento de Copan, Honduras
G. Heiken, N. Ramos, W. Duffield, J. Musgrave, K. Wohletz, S. Priest, J. Aldrich, W. Flores, A. Ritchie, F. Goff, D. Eppler, C. Escobar
1991, Journal of Volcanology and Geothermal Research (45) 41-58
Platanares is located 16 km west of Santa Rosa de Copan, Honduras, along the Quebrada del Agua Caliente. The thermal manifestations are along faults in tuffs, tuffaceous sedimentary rocks, and lavas of the Padre Miguel Group. These tuffs are silicified near the faults, are fractured, and may provide the fracture...
Pre-exploitation state of the Ahuachapán geothermal field, El Salvador
Z. Aunzo, C. Laky, B. Steingrimsson, G.S. Bodvarsson, M.J. Lippmann, A.H. Truesdell, C. Escobar, A. Quintanilla, G. Cuellar
1991, Geothermics (20) 1-22
The lithology and structural features of the Ahuachapán geothermal area and their impact on the movement of cold and hot fluids within the system are described, as well as the development and evaluation of the natural state model of the field. Four major lithologic units are present in Ahuachapán and...
Biological response of Thrush Lake, Minnesota, to a protective liming treatment
D. Wright, M. Danks, W. Popp, P. Eiler, R.K. Schreiber
H. Olem, R.K. Schreiber, R.W. Brocksen, D.B. Porcella, editor(s)
1991, Book chapter, International Lake and Watershed Liming Practices
No abstract available at this time...
Visible and near-infrared (0.4-2.5 μm) reflectance spectra of playa evaporite minerals
James K. Crowley
1991, Journal of Geophysical Research (96) 16231-16240
Visible and near-infrared (VNIR; 0.4–2.4 μm) reflectance spectra were recorded for 35 saline minerals that represent the wide range of mineral and brine chemical compositions found in playa evaporite settings. The spectra show that many of the saline minerals exhibit diagnostic near-infrared absorption bands, chiefly attributable to vibrations of hydrogen-bonded...
The late Cenozoic diatom stratigraphy and paleolimnology of Tule Lake, Siskiyou Co. California
J.P. Bradbury
1991, Journal of Paleolimnology (6) 205-255
Lacustrine diatoms are diverse, well preserved and abundant in cores of lake sediment to 334 m depth near the town of Tulelake, Siskiyou County, northern California. The cores have been dated by radiometric, tephrochronologic and paleomagnetic techniques, which indicate a basal age of about 3 million years (Ma) and a...
Convergent radial dispersion: A note on evaluation of the Laplace transform solution
Allen F. Moench
1991, Water Resources Research (27) 3261-3264
A numerical inversion algorithm for Laplace transforms that is capable of handling rapid changes in the computed function is applied to the Laplace transform solution to the problem of convergent radial dispersion in a homogeneous aquifer. Prior attempts by the author to invert this solution were unsuccessful for highly advective...
Field and modelling studies of immiscible fluid flow above a contaminated water-table aquifer
W.N. Herkelrath, H.I. Essaid, K.M. Hess
1991, Conference Paper, National Conference Publication - Institution of Engineers, Australia
A method was developed for measuring the spatial distribution of immiscible liquid contaminants in the subsurface. Fluid saturation distributions measured at a crude-oil spill site were used to test a numerical multiphase flow model....
Capture zones for simple aquifers
Carl D. McElwee
1991, Ground Water (29) 587-590
Abstract. The protection and cleanup of aquifers is a matter of high priority for all states and the federal government. One concept that is receiving increased attention is that of wellhead protection. Capture zones showing the area influenced by a well within a certain time are...
Fate of silicate minerals in a peat bog
Philip C. Bennett, Donald I. Siegel, Barbara M. Hillier, Paul H. Glaser
1991, Geology (19) 328-331
An investigation of silicate weathering in a Minnesota mire indicates that quartz and aluminosilicates rapidly dissolve in anoxic, organic-rich, neutral- pH environments. Vertical profiles of pH, dissolved silicon, and major cations were obtained at a raised bog and a spring fen and compared. Profiles of readily extractable silicon, diatom...
Is the extent of glaciation limited by marine gas-hydrates?
Charles K. Paull, William Ussler III, William P. Dillon
1991, Geophysical Research Letters (18) 432-434
Methane may have been released to the atmosphere during the Quaternary from Arctic shelf gas-hydrates as a result of thermal decomposition caused by climatic warming and rising sea-level; this release of methane (a greenhouse gas) may represent a positive feedback on global warming [Revelle, 1983; Kvenvolden, 1988a; Nisbet, 1990]. We...
Regional assessment of nonpoint-source pesticide residues in ground water, San Joaquin Valley, California
Joseph L. Domagalski, N. M. Dubrovsky
1991, Water-Resources Investigations Report 91-4027
No abstract available....
Influence of pycnocline topography and water-column structure on marine distributions of alcids (Aves: Alcidae) in Anadyr Strait, Northern Bering Sea, Alaska
J. Christopher Haney
1991, Marine Biology (110) 419-435
Systematic ship-board surveys were used to simultaneously record seabird abundances and resolve coarse-scale (3 to 10 km) horizontal and fine-scale (1 to 10 m) vertical variability in water-column structure and bathymetry for portions of the coastal zone in Anadyr Strait near western St. Lawrence Island, northern Bering Sea, Alaska, during...
Effect of anisotropy on ground-water dis charge to streams in fractured Mesozoic-basin rocks
J. C. Lewis
1991, Book chapter, Aquifers of the southern and eastern states
No abstract available ...
Areal extent, hydrogeologic characteristics, and possible origins of the carbonate rock Newburg Zone (Middle-Upper Silurian) in Ohio
M.L. Strobel, E. F. Bugliosi
1991, Ohio Journal of Science (91) 209-215
The zone occurs in carbonate rocks of Middle to Late Silurian age across much of Ohio. Known also to well drillers as the "Second Water' in the "Big Lime' carbonate sequence, the Newburg zone is a source of hydrocarbons in northeast Ohio, brines in southeast Ohio, and a widespread source...
Petrogenesis and geological history of a uranium source rock: a case study in northeastern Washington, U.S.A.
R. A. Zielinski, R.C. Burruss
1991, Applied Geochemistry (6) 597-612
A small (4 km2) drainage basin in northeastern Washington contains highly uraniferous groundwater and highly uraniferous peaty sediments of Holocene age. The U is derived from granitic bedrock that underlies the entire drainage basin and that contains 9–16 ppm U. This...
Green coloration of recently laid black-crowned night-heron eggs
T. W. Custer
1991, Colonial Waterbirds (14) 184-185
Color of Black-crowned Night-Heron (Nycticorax nycticorax ) eggs of known laying order was quantified in a Wisconsin colony. Eggs were of greener intensity on the day of laying and one day thereafter than earlier laid eggs within a clutch. Egg color can be used to identify clutches within...
Compsopogon cf. coeruleus, a benthic red alga (Rhodophyta) new to the Laurentian Great Lakes
Bruce A. Manny, Thomas A. Edsall, Daniel E. Wujek
1991, Canadian Journal of Botany (69) 1237-1240
We found Compsopogon cf. coeruleus for the first time in the Laurentian Great Lakes, growing on limestone rocks at a depth of 21 m on Six Fathom Bank in central Lake Huron. It is the first freshwater red alga to be found in the Great Lakes and the only red alga ever found on an...
An overview of the U.S. Fish and Wildlife Service mitigation research program
R.K. Schreiber, R.F. Villella
H. Olem, R.K. Schreiber, R.W. Brocksen, D.B. Porcella, editor(s)
1991, Book chapter, International Lake and Watershed Liming Practices
No abstract available at this time...
