Precise U‐Pb ages of Duluth Complex and related mafic intrusions, northeastern Minnesota: Geochronological insights to physical, petrogenetic, paleomagnetic, and tectonomagmatic processes associated with the 1.1 Ga Midcontinent Rift System
James B. Paces, James D. Miller Jr.
1993, Journal of Geophysical Research B: Solid Earth (98) 13997-14013
Precise resolution of the timing of igneous activity is crucial to understanding the dynamic processes associated with continental rifting. Mafic intrusive rocks constitute a major portion of the exposed 1100 Ma (Keweenawan) Midcontinent Rift system in northeastern Minnesota; however, prior to this study, geochronological data were insufficient to allow rigorous...
Chronic toxicity of Pydraul 50E to lake trout
Foster L. Mayer, Daniel F. Woodward, William J. Adams
1993, Bulletin of Environmental Contamination and Toxicology (51) 289-295
Industrial phosphate esters, both triaryl and alkyl aryl phosphate esters, are used as fire resistant hydraulic fluids and as fire retardant plasticizers (Lapp 1976). Hydraulic fluids probably represent the largest contribution of phosphate ester compounds released into the environment. Lapp (1976) estimated that 65 to 70 percent of all phosphate...
Evaluating landsat thematic mapper derived vegetation indices for estimating above-ground biomass on semiarid rangelands
G.L. Anderson, J. D. Hanson, R. H. Haas
1993, Remote Sensing of Environment (45) 165-175
Ground data from the Central Plains Experimental Range in northeast Colorado and Landsat satellite images of that area acquired in August 1989, June 1990, and September 1990 were used to evaluate the level of association that can be expected from a univariate model relating spectrally derived vegetation indices (difference, ratio,...
Estimating discharge of shallow groundwater by transpiration from greasewood in the Northern Great Basin
William D. Nichols
1993, Water Resources Research (29) 2771-2778
Evapotranspiration from bare soil and phreatophytes is a principal mechanism of groundwater discharge in arid and semiarid regions of the midwestern and western United States including the Great Basin. The imbalance between independent estimates of groundwater recharge from precipitation and of groundwater discharge based on estimates of groundwater evapotranspiration leads...
Site response estimates in Salt Lake Valley, Utah, from borehole seismic velocities
R. A. Williams, K. W. King, John Tinsley
1993, Bulletin of the Seismological Society of America (83) 862-889
The general correlation of Salt Lake Valley sites located on soft, saturated unconsolidated silty and clayey deposits (that is, deposits with low S-wave velocity) with high seismic amplification at the ground surface motivated our investigation of the relationship between the P- and S-wave seismic velocity (Vp and Vs) of these units and their corresponding observed...
Determination of size and element composition distributions of complex colloids by sedimentation field-flow fractionation—inductively coupled plasma mass spectrometry
Deirdre M. Murphy, John R. Garbarino, Howard E. Taylor, Ronald Beckett, B. Hart
1993, Journal of Chromatography A (642) 459-467
Sedimentation field-flow fractionation (SdFFF) and inductively coupled plasma mass spectrometry (ICP-MS) have been directly combined and the resulting SdFFF-ICP-MS instrument can be used to produce element based size distributions of colloidal samples. Using appropriate tracer elements the size distributions of specific components can be picked out from a complex mixture....
Multivariate geostatistical analysis of ground-water contamination: A case history
Jonathan D. Istok, Jeffrey D. Smyth, Alan L. Flint
1993, Groundwater (31) 63-74
A case history is presented for the application of multivariate geostatistical methods to the problem of estimating pesticide concentrations in ground water from measured concentrations of nitrate and pesticide, when pesticide is under‐sampled. The shallow, poorly confined, sand and gravel aquifer underlying the lower Malheur River basin near Ontario, Oregon...
Overwinter distribution of northern pintail populations in North America
Jay B. Hestback
1993, Journal of Wildlife Management (57) 582-589
Northern pintails (Anas acuta) exist as a single circumpolar breeding population but display weak fidelity to given breeding sites. If fidelity to wintering areas is strong, management on wintering grounds may allow local winter populations to increase. Thus, I delineated reference areas for wintering areas based on recovery data for...
Survival of northern pintails banded during winter in North America, 1950-88
Jay B. Hestbeck
1993, Journal of Wildlife Management (57) 590-597
From 1950 through 1988, the continental breeding population of northern pintails (Anas acuta) varied from 2.0 million to 9.9 million. Because pintails have high fidelity to certain wintering grounds along coasts and large bodies of water, management on these wintering areas may increase population size if changes in winter survival...
Landslides triggered by the storm of November 3-5, 1985, Wills Mountain Anticline, West Virginia and Virginia
Robert B. Jacobson, John P. McGeehin, Elizabeth D. Cron, Carolyn E. Carr, John M. Harper, Alan D. Howard
1993, Bulletin 1981-C
More than 3,000 landslides were triggered by heavy rainfall in the central Appalachian Mountains of West Virginia and Virginia, November 3-5, 1985. These landslides provided the opportunity to study spatial controls on landslides, magnitude and frequency of triggering events, and the effects of landslides on flood-induced geomorphic change. The study...
Transport of volatile organic compounds across the capillary fringe
Kathleen A. McCarthy, Richard L. Johnson
1993, Water Resources Research (29) 1675-1683
Physical experiments were conducted to investigate the transport of a dissolved volatile organic compound (trichloroethylene, TCE) from shallow groundwater to the unsaturated zone under a variety of conditions including changes in the soil moisture profile and water table position. Experimental data indicated that at moderate groundwater velocities (0.1 m/d), vertical...
Simulation of fluid distributions observed at a crude oil spill site incorporating hysteresis, oil entrapment, and spatial variability of hydraulic properties
H.I. Essaid, W.N. Herkelrath, K.M. Hess
1993, Water Resources Research (29) 1753-1770
Subsurface oil, water, and air saturation distributions were determined using 146 samples collected from seven boreholes along a 120-m transect at a crude oil spill site near Bemidji, Minnesota. The field data, collected 10 years after the spill, show a clearly defined oil body that has an oil saturation distribution...
Transport and accumulation of radionuclides and stable elements in a Missouri River Reservoir
Edward Callender, John A. Robbins
1993, Water Resources Research (29) 1787-1804
Several long sediment cores from the Cheyenne River Embayment of Lake Oahe, a 250-km-long Missouri River reservoir in South Dakota, have been analyzed for radionuclides and stable elements. The combination of fine-scale sampling and rapid sedimentation produces radionuclide distributions that can be used to estimate the detailed chronology of particle...
Use of output from high‐resolution atmospheric models in landscape‐scale hydrologic models: An assessment
S. W. Hostetler, F. Giorgi
1993, Water Resources Research (29) 1685-1695
In this paper we investigate the feasibility of coupling regional climate models (RCMs) with landscape‐scale hydrologic models (LSHMs) for studies of the effects of climate on hydrologic systems. The RCM used is the National Center for Atmospheric Research/Pennsylvania State University mesoscale model (MM4). Output from two year‐round simulations (1983 and...
Toward the simulation of the effects of the Great Lakes on regional climate
Gary T. Bates, F. Giorgi, Steven W. Hostetler
1993, Monthly Weather Review (121) 1373-1387
This paper describes a set of numerical experiments aimed at evaluating the feasibility of applying a version of the National Center for Atmospheric Research-Pennsylvania State University regional model (MM4) to regional climate simulation over the Great Lakes Basin. The objectives of this initial modeling investigation are 1) to examine whether...
Geochemical evaluation of upper cretaceous fruitland formation coals, San Juan Basin, New Mexico and Colorado
G.E. Michael, D.E. Anders, B. E. Law
1993, Organic Geochemistry (20) 475-498
Geochemical analyses of coal samples from the Upper Cretaceous Fruitland Formation in the San Juan Basin of New Mexico and Colorado were used to determine thermal maturity, type of kerogen, and hydrocarbon generation potential. Mean random vitrinite reflectance (%Rm) of the Fruitland coal ranges from 0.42 to 1.54%. Rock-Eval pyrolysis...
Northward displacements of forearc slivers in the Coast Ranges of California and Southwest Oregon during the late Mesozoic and early Cenozoic
A. S. Jayko, M.C. Blake Jr.
1993, Book chapter, Mesozoic paleogeography of the Western United States
North American-Farallon-Kula plate motion data, combined with estimated strikeslip displacements obtained from the obliquity of convergence along active circumPacific subduction zones, can be used to estimate the amount of strike-slip displacement along the forearc region of western North America. This evidence suggests a minumum of 500 km and maximum of...
First results of a deep tow CHIRP sonar seafloor imaging system
M. Parent, Changle Fang, Thomas F. O’Brien, William W. Danforth
1993, Conference Paper
The latest and most innovative technology has been applied towards the development of a full-ocean depth multi-sensor sonar system using linear swept-FM (Chirp) technology. The seafloor imaging system (SIS- 7000) described herein uses Chirp sidescan sonar to provide high resolution imagery at long range, and Chirp subbottom sonar to provide...
A Geographic Information System procedure to quantify drainage-basin characteristics
David A. Eash
1993, Conference Paper, Proceedings of the Symposium on Geographic Information Systems and Water Resources
The Basin Characteristics System (BCS) has been developed to quantify characteristics of a drainage basin. The first of four main BCS processing steps creates four geographic information system (GIS) digital maps representing the drainage divide, the drainage network, elevation contours, and the basin length. The drainage divide and basin...
A spatial simulation model of hydrology and vegetation dynamics in semi-permanent prairie wetlands
Karen A. Poiani, W. Carter Johnson
1993, Ecological Applications (3) 279-293
The objective of this study was to construct a spatial simulation model of the vegetation dynamics in semi-permanent prairie wetlands. A hydrologic submodel estimated water levels based on precipitation, runoff, and potential evapotranspiration. A vegetation submodel calculated the amount and distribution of emergent cover and open water using a geographic...
Sediment export by ice rafting from a coastal Polynya, Arctic Alaska, U.S.A.
Erk Reimnitz, Michael McCormick, Kristin McDougall-Reid, Elisabeth M. Brouwers
1993, Arctic and Alpine Research (25) 83-98
Strong offshore winds in early 1989 produced a shore polynya that reached along the entire north coast of Alaska and eastward beyond the mouth of the Mackenzie River in Canada. From January through April, this open water periodically exposed the shelf to sediment entrainment by suspension freezing. This process requires...
Conceptual model for quantifying pre-smolt production from flow-dependent physical habitat and water temperature
S. C. Williamson, J. M. Bartholow, C. B. Stalnaker
1993, Regulated Rivers: Research & Management (8) 15-28
A conceptual model has been developed to test river regulation concepts by linking physical habitat and water temperature with salmonid population and production in cold water streams. Work is in progress to examine numerous questions as part of flow evaluation and habitat restoration programmes in the...
Comparison of Penman-Monteith, Shuttleworth-Wallace, and modified Priestley-Taylor evapotranspiration models for wildland vegetation in semiarid rangeland
David I. Stannard
1993, Water Resources Research (29) 1379-1392
Eddy correlation measurements of sensible and latent heat flux are used with measurements of net radiation, soil heat flux, and other micrometeorological variables to develop the Penman-Monteith, Shuttleworth-Wallace, and modified Priestley-Taylor evapotranspiration models for use in a sparsely vegetated, semiarid rangeland. The Penman-Monteith model, a one-component model designed for use...
The use of NOAA AVHRR data for assessment of the urban heat sland effect
K. P. Gallo, A. L. McNab, Thomas R. Karl, Jesslyn F. Brown, J. J. Hood, J.D. Tarpley
1993, Journal of Applied Meteorology and Climatology (32) 899-908
A vegetation index and a radiative surface temperature were derived from satellite data acquired at approximately 1330 LST for each of 37 cities and for their respective nearby rural regions from 28 June through 8 August 1991. Urbanrural differences for the vegetation index and the surface temperatures were computed and...
Broad trends in geomagnetic paleointensity on Hawaii during Holocene time
Edward A. Mankinen, Duane E. Champion
1993, Journal of Geophysical Research B: Solid Earth (98) 7959-7976
Paleointensity determinations have been obtained from 22 basaltic lava flows on the island of Hawaii using the Thelliers' method. Radiocarbon dating indicates that these flows erupted at intervals ranging from about 200 to 1000 years, and results of the experiments provide an estimate of broad trends in geomagnetic paleointensity during...
