Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

165605 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 4742, results 118526 - 118550

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Distribution and origin of sulfur in Colorado oil shale
John R. Dyni
1983, Conference Paper, Oil Shale Symposium Proceedings
The sulfur content of 1,225 samples of Green River oil shale from two core holes in the Piceance Creek Basin, Colorado, ranges from nearly 0 to 4.9 weight percent. In one core hole, the average sulfur content of a sequence of oil shale 555 m thick, which represents nearly the...
Changes in phototaxis during early development of walleye
L. Bulkowski, J. W. Meade
1983, Transactions of the American Fisheries Society (112) 445-447
Phototaxis of walleyes Stizostedion vitreum vitreum was examined during the first 11 weeks of larva and juvenile development. Fish were subjected to six light intensities ranging from 2 to 34 lux, plus 7,800 lux as an extreme. The number of fish positioned in each light intensity was used to determine...
Magnetic models of crystalline terrane; accounting for the effect of topography
Richard J. Blakely, V. J. Grauch
1983, Geophysics (48) 1551-1557
Igneous rocks commonly have large magnetic susceptibilities so that high topographic relief in crystalline terrane can produce significant anomalies in aeromagnetic surveys. Topographic anomalies are particularly significant in relatively undeformed volcanic terrane because young volcanic rocks generally have large natural remanent magnetizations as well as large susceptibilities. These anomalies commonly...
Airborne biogeophysical mapping of hidden mineral deposits
William Collins, Sheng-Huei Chang, G. L. Raines, Frank C. Canney, Roger P. Ashley
1983, Economic Geology (78) 737-749
Airborne survey techniques have been developed to detect and map forest canopies affected by metal-induced stress. A high spectral resolution airborne spectroradiometer system, used over a known forest-covered copper soil anomaly, has revealed previously unknown spectral changes in the near-infrared chlorophyll absorption spectrum. The metal-induced spectral shifts have subsequently been...
Intrusive rocks and plutonic belts of southeastern Alaska, U.S.A
David A. Brew, Robert P. Morrell
1983, GSA Memoirs (159) 171-194
About 30 percent of the 175,000-km2 area of southeastern Alaska is underlain by intrusive igneous rocks. Compilation of available information on the distribution, composition, and ages of these rocks indicates the presence of six major and six minor plutonic belts.From west to east, the major belts are: the Fairweather-Baranof belt of...
Crassulacean acid metabolism in Isoetes bolanderi in high elevation oligotrophic lakes
Jon E. Keeley, C.M. Walker, R.P. Mathews
1983, Oecologia (58) 63-69
Isoetes bolanderi dominates the littoral flora of Siesta (elevation 2,440 m) and Ellery (2,905 m) lakes in the Sierra Nevada Range of California, USA. Both lakes are sparsely vegetated and I. bolanderi maintained aboveground oven dry weight of 30–50 m−22 through most of the 1981 summer growing season. Plants at the higher elevation Ellery...
Crassulacean acid metabolism in the seasonally submerged aquatic Isoetes howellii
Jon E. Keeley
1983, Oecologia (58) 57-62
Evidence to date is consistent with the hypothesis that the submerged aquatic Isoetes howellii Engelmann possesses crassulacean acid metabolism. Quantitative 14C uptake studies indicate that CO2 assimilation in both the light and dark are functions of pH and total inorganic carbon level. In both the light and dark, maximum uptake rates in 0.6 mM...
The relationship between harvest and survival rates of mallards: A straightforward approach with partitioned data sets
James D. Nichols, James E. Hines
1983, Journal of Wildlife Management (47) 334-348
We randomly partitioned mallard (Anas platyrhynchos) bandings and recoveries from each of a number of selected reference areas into 2 groups and estimated survival and harvest rates for each area and group. This procedure produced independent vectors of survival- and harvest-rate estimates, which were used to test the general hypothesis...
Body shot in Atlantic brant
Ronald E. Kirby, Holliday H. Obrecht III, Matthew C. Perry
1983, Journal of Wildlife Management (47) 527-530
No abstract available. ...
Comparison of stable isotope reference samples
Tyler B. Coplen, Carol Kendall, Jessica A. Hopple
1983, Nature (302) 236-238
Use of light stable isotope ratio measurements has proliferated in the past decade. The need for procuring additional stable isotope reference materials was recognized at an International Atomic Energy Agency (IAEA) consultants' meeting convened in 19761. This group recommended acquisition of two carbonates, two carbon dioxide samples, a biotite, a...
Correlation of changes in gravity, elevation, and strain in southern California
R.C. Jachens, W. Thatcher, C. W. Roberts, R.S. Stein
1983, Science (219) 1215-1217
Measurements made once or twice a year from 1977 through 1982 show large correlated changes in gravity, elevation, and strain in several southern California networks. Precise gravity surveys indicate changes of as much as 25 microgals between surveys 6 months apart. Repeated surveys show that annual elevation...
The Giles County, Virginia, seismic zone
G. A. Bollinger, R. L. Wheeler
1983, Science (219) 1063-1065
A well-defined seismic zone recently detected in Virginia has an orientation that is not related to the surrounding geologic structures. The orientation of the zone appears to be related to features below the Appalachian overthrust belt. A damaging earthquake that is important in evaluating seismic hazard in the southeastern United...
Temporal accumulation of organochlorine pesticides in shorebirds wintering on the south Texas coast, 1979-80
Donald H. White, Christine A. Mitchell, T. Earl Kaiser
1983, Archives of Environmental Contamination and Toxicology (12) 241-245
Organochlorine pesticide residues were determined in 168 shorebirds of three species collected at approximate bimonthly intervals during the fall and winter months of 1979–80 near Port Mansfield on the south Texas coast. The study was conducted to determine if shorebirds wintering on mudflats at the outlets of agricultural drains in...
Platte River Forum for the Future: workshop model documentation
1983, Report
The Platte River Forum for the Future (PRFF) is an effort by the Nebraska Natural Resources Commission (NNRC) to bring together representatives of interests and agencies concerned with management of the Platte River and, assisted by various computer technologies, to reach some degree of agreement on the “best uses” of...
Evaluating environmental and economic consequences of alternative pest management strategies: results of modeling workshops
Richard L. Johnson, Austin K. Andrews, Gregor T.L. Auble, Richard A. Ellison, David B. Hamilton, James E. Roelle, Peter J. McNamee
1983, Report
The U.S. Environmental Protection Agency (EPA) needs a comprehensive method to evaluate the human health and environmental effects of alternative agricultural pest management strategies. This project explored the utility of Adaptive Environmental Assessment (AEA) techniques for meeting this need. The project objectives were to produce models for environmental...
Groundwater observation network design for the Kansas groundwater management districts, U.S.A.
M. Sophocleous
1983, Journal of Hydrology (61) 371-389
Concerns about the efficiency and economic soundness of the Kansas groundwater monitoring program led to a systematic redesign of this network, a tentative phase of which is presented in this study. The objectives of this paper include monitoring of major aquifers within each groundwater management district at a spatially more...
Distribution of larval fishes related to potential navigation impacts on the upper Mississippi River, pool 7
L. E. Holland, J.R. Sylvester
1983, Transactions of the American Fisheries Society (112) 293-301
Ichthyoplankton samples were collected twice monthly during spring and summer 1981 from a variety of habitats in Navigation Pool 7 of the upper Mississippi River. Larval‐fish distributions in the pool and variations in those distributions were analyzed relative to potential impacts of increased commercial navigation. Although as...
Upper Cenozoic silicoflagellates from offshore Ecuador, Deep Sea Drilling Project Site 504
David Bukry
1983, Initial Reports of the D.S.D.P. (69) 321-342
Diverse and abundant late Miocene to Pleistocene silicoflagellates at DSDP Site 504 can be correlated by tropical biostratigraphic zones and relative paleotemperature values to eastern tropical Pacific reference site DSDP 503A farther to the west. Early Pliocene assemblages, which were poorly known until now, are present and can be correlated...