Hydrology, water quality, and simulation of ground-water flow at a taconite-tailings basin near Keewatin, Minnesota
C. F. Myette
1991, Water-Resources Investigations Report 88-4230
Taconite tailings, a waste product from processing of iron ore, have been deposited in a 2.5-square-mile containment basin near Keewatin, Minnesota, The basin, which is bounded by earthen dikes of compacted drift and clayey bouldery till, contains saturated tailings consisting of chert and other silica-rich particles that range from clay...
An Axisymmetric finite-difference flow model to simulate drawdown in and around a pumped well
A. T. Rutledge
1991, Water-Resources Investigations Report 90-4098
Surficial geologic map of the Steamboat Springs 30' x 60' quadrangle, Grand, Jackson, and Routt counties, Colorado
R.F. Madole
1991, IMAP 1825
This map is one of a series of four 30' x 60' surficial geologic maps (1:100,000 scale) intended to provide basic geologic information for planning for energy resource development and growth in northwestern Colorado. An effort is made to characterize all surficial materials, regardless of origin. Hence, residuum is given...
An interactive code (NETPATH) for modeling NET geochemical reactions along a flow PATH
Niel Plummer, E.C. Prestemon, D.L. Parkhurst
1991, Water-Resources Investigations Report 91-4078
No abstract available....
Delineation of recharge areas for selected wells in the St. Peter-Prairie du Chien-Jordan Aquifer, Rochester, Minnesota
G. N. Delin, James Edward Almendinger
1991, Open-File Report 90-397
Accurate delineation of recharge areas for wells is an important requisite to protecting ground-water quality. Zones of transport and zones of contribution are two types of recharge areas that can be delineated. Analytical-calculation, numerical-modeling, and hydrogeologic-mapping methods were used to delineate recharge areas for two high-capacity (greater than about 200...
Marion Peak quadrangle, Fresno County, California— Analytic data
James Gregory Moore
1991, Bulletin 1986
The Marion Peak 15-minute quadrangle includes about 620 km2 on the west slope of the Sierra Nevada in Fresno County, California, between 36°45' and 37°00' N. latitude and 118°30' and 118°45 W. longitude. This report supplements the geologic map of the Marion Peak quadrangle by providing modal and chemical analyses...
A steady-state unsaturated-zone model to simulate pesticide transport
A. T. Rutledge, J. O. Helgesen
1991, Water-Resources Investigations Report 90-4164
No abstract available....
Gold deposits related to greenstone belts in Brazil; deposit modeling workshop; Part A, excursions
Charles H. Thorman, Eduardo A. Ladeira, Diane C. Schnabel
1991, Bulletin 1980-A
Documentation of model input and output values for simulation of regional ground-water flow, carbonate-rock province, Nevada, Utah, and adjacent states
D. H. Schaefer
1991, Open-File Report 91-479
Crustal structure interpreted from magnetic anomalies
Jeffrey Phillips, Richard J. Reynolds, Herbert Frey
1991, Reviews of Geophysics (29) 416-427
In this review, we discuss publications during the last quadrennium (1987–1990) that used aeromagnetic data, marine magnetic data, satellite magnetic data, and rock magnetic and petrologic data to provide information on the sources of magnetic anomalies. Abstracts and papers by non‐U.S. authors are not described.The publications reviewed reflect increased integration...
Ecosystem modeling of Barataria Basin, Louisiana utilizing desktop parallel technology
M. L. White, T. Maxwell, R. Costanza, Thomas W. Doyle
1991, Conference Paper, 27th Annual Conference : Water management of river systems, and symposium: Resource development of the lower Mississippi River
No abstract available....
Fractal hierarchies of magma transport in Hawaii and critical self- organization of tremor
H. R. Shaw, B. Chouet
1991, Journal of Geophysical Research (96) 10,191-10,207
A hierarchical model of magma transport in Hawaii is developed from the seismic records of deep (30-60 km) and intermediate-depth (5-15 km) harmonic tremor between January 1, 1962, and December 31, 1983. A tremor model of magma transport is developed from mass balances of percolation that are proportional to tremor...
USFWS selected geographic analyses
Floyd O. Stayner, James D. Scurry, James B. Johnston, Mary C. Watzin, Pasquale F. Roscigno
1991, Conference Paper, Coastal zone '91: Proceedings of the seventh symposium on coastal and ocean management
The geographic information system (GIS) used by the National Wetlands Research Center (NWRC) of the U.S. Fish and Wildlife Service has been valuable in assisting natural resource managers in planning and managing coastal fish and wildlife resources. In the past 5 years, NWRC has conducted about 60 studies employing this...
Global climate change: USFWS coastal research
Janet R. Keough, Thomas W. Doyle, Robert E. Stewart Jr.
1991, Conference Paper, Coastal zone '91 : Proceedings of the seventh symposium on coastal and ocean management
Scenarios of global climate change are still ambiguous; however, increasing sea level and atmospheric carbon dioxide (CO2) concentrations seem certain, although rates of change are still being debated. Predictions for other aspects of climate change, such as temperature, tropical storm frequency and intensity, and precipitation, are still in debate, and...
Reproductive outcomes in colonial fish-eating birds: A biomarker for developmental toxicants in Great Lakes food chains: I. Historical and ecotoxicological perspectives
Glen Fox, D. V. Weseloh, Timothy J. Kubiak, Thomas C. Erdman
1991, Journal of Great Lakes Research (17) 153-157
Colonial fish-eating birds have been used as convenient model populations in which to study the impact of chronic exposure to complex mixtures of persistent lipophilic environmental contaminants within the Great Lakes ecosystem. To date, published reports of contaminant-induced adverse reproductive outcomes exist for six species. We briefly review the studies...
Evaluation of wetland development and waterbird response at Elk Creek Wildlife management area, Lake Mills, Iowa, 1961 to 1990
M.W. Weller, G.W. Kaufmann, P.A. Vohs
1991, Wetlands (11) 245-262
A waterfowl habitat development project along 7.5 miles (12.07 km) of stream was evaluated after 27 years. There was a modest 12% net increase in wetlands in impounded areas, but much of the wetland vegetation changed from seasonally flooded, nonpersistent and persistent emergents to shallow, open-water areas. An unimpounded, downstream reference area...
An axial view of a metamorphic core complex: Crustal structure of the Whipple and Chemehuevi Mountains, southeastern California
J. M. Wilson, Jill McCarthy, R.A. Johnson, Keith A. Howard
1991, Journal of Geophysical Research B: Solid Earth (96) 12293-12311
A 135‐km‐long, NW‐SE trending, seismic refraction/wide‐angle reflection profile provides a unique along‐strike view of the crustal structure of a belt of metamorphic core complexes in southeastern California: the Whipple, Chemehuevi, and Sacramento mountains metamorphic core complexes. Interpretation of the seismic data was done by two‐dimensional forward modeling of travel times...
Modes of cross-shore sediment transport on the shoreface of the Middle Atlantic Bight
L.D. Wright, John D. Boon, S.C. Kim, J. H. List
1991, Marine Geology (96) 19-51
The mechanisms responsible for onshore and offshore sediment fluxes across the shoreface zone seaward of the surf zone were examined in a 3-year field study. The study was conducted in the southern part of the Middle Atlantic Bight in the depth region 7–17 m using instrumented tripods supporting electromagnetic current...
Numerical simulations of hydrothermal circulation resulting from basalt intrusions in a buried spreading center
A.T. Fisher, T.N. Narasimhan
1991, Earth and Planetary Science Letters (103) 100-115
A two-dimensional, one by two-kilometer section through the seafloor was simulated with a numerical model to investigate coupled fluid and heat flow resulting from basalt intrusions in a buried spreading center. Boundary and initial conditions and physical properties of both sediments and basalt were constrained by field surveys and drilling...
Volcano spacing and plate rigidity
Uri S. ten Brink
1991, Geology (19) 397-400
In-plane stresses, which accompany the flexural deformation of the lithosphere under the load of adjacent volcanoes, may govern the spacing of volcanoes in hotspot provinces. Specifically, compressive stresses in the vicinity of a volcano prevent new upwelling in this area, forcing a new volcano to develop at a minimum distance...
Wave processes and geologic responses on the floor of the Yellow Sea
James S. Booth, William J. Winters
1991, Book chapter, From shoreline to abyss: Contributions in marine geology in honor of Francis Parker Shepard
The floor of the Yellow Sea is a geologically mundane surface: it is nearly horizontal, lacks relief, and, with few exceptions, is devoid of conspicuous geomorphologic features. However, it is the principal repository for the prodigious sediment load of the Huanghe (Yellow River); and, due to its inherent shallowness (average...
Transient eddy formation around headlands
Richard P. Signell, W. Rockwell Geyer
1991, Journal of Geophysical Research (96) 2561-2575
Eddies with length scales of 1-10 km are commonly observed in coastal waters and play an important role in the...
Geochemical evolution of acidic ground water at a reclaimed surface coal mine in western Pennsylvania
Charles A. Cravotta III,
1991, Conference Paper, Proceedings American Society of Mining and Reclamation, 1991
Concentrations of dissolved sulfate and acidity in ground water increase downflow in mine spoil and underlying bedrock at a reclaimed surface coal mine in the bituminous field of western Pennsylvania. Elevated dissolved sulfate and negligible oxygen in ground water from bedrock about 100 feet below the water table suggest that...
Speculations on continental crustal evolution
R. Meissner, Walter D. Mooney
1991, Eos, Earth and Space Science News (72) 585-590
The evolution of the continental crust is a topic that has challenged Earth scientists since the earliest hypotheses of crustal evolution were put forth by such luminaries as Hutton, the 18th century Scottish scientist, and later by Stille (Germany), Argand (France), and Dana (United States). Recent geophysical observations provide important...
The velocity field along the San Andreas Fault in central and southern California
Michael Lisowski, James C. Savage, W.H. Prescott
1991, Journal of Geophysical Research B: Solid Earth (96) 8369-8389
The velocity field within a 100‐km‐broad zone centered on the San Andreas fault between the Mexican border and San Francisco Bay has been inferred from repeated surveys of trilateration networks in the 1973–1989 interval. The velocity field has the appearance of a shear flow that remains parallel to the local...
