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

165626 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 4452, results 111276 - 111300

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Obstacles facing the Venus radar mapper - The implications of gestalt formation in stereo-radargrammetry
R.L. Wildey
1986, Earth, Moon and Planets (36) 41-48
The question of adapting to radar images the existing hardware that form topographic maps through stereo-photogrammetric models, is examined in principle. Such hardware utilizes a human/computer hybrid. Although the problem of brightness differentials between corresponding landmarks can be dealt with pseudo-photoclinometrically, the main problem is whether the perspective in a...
U.S. Geological Survey toxic Waste-Groundwater Contamination Program, fiscal year 1985
S.E. Ragone
1986, Environmental Geology and Water Sciences (8) 129-132
In fiscal year 1982, the U S Geological Survey began an interdisciplinary research thrust entitled Toxic Waste-Groundwater Contamination Program The objective of the thrust was to provide earth sciences information necessary to evaluate and mitigate existing groundwater contamination problems resulting from the planned or inadvertant disposal...
Recent developments in the U. S. Geological Survey's Landsat image mapping program
Frederick S. Brownworth, Wayne G. Rohde
1986, Conference Paper, Technical Papers of the American Society of Photogrammetry, Fall Technical Meeting
At the 1984 ASPRS-ACSM Convention in Washington, D. C. a paper on 'The Emerging U. S. Geological Survey Image Mapping Program' was presented that discussed recent satellite image mapping advancements and published products. Since then Landsat image mapping has become an integral part of the National Mapping Program. The Survey...
Changes in complex resistivity during creep in granite
D.A. Lockner, J.D. Byerlee
1986, Pure and Applied Geophysics PAGEOPH (124) 659-676
A sample of Westerly granite was deformed under constant stress conditions: a pore pressure of 5 MPa, a confining pressure of 10 MPa, and an axial load of 170 MPa. Pore volume changes were determined by measuring the volume of pore fluid (0.01 M KClaq) injected into the sample. After...
Geochemical exploration for mineralized breccia pipes in northern Arizona, U.S.A.
K. J. Wenrich
1986, Applied Geochemistry (1) 469-485
Thousands of solution-collapse breccia pipe crop out in the canyons and on the plateaus of northern Arizona. Over 80 of these are known to contain U or Cu mineralized rock. The high-grade U ore associated with potentially economic concentrations of Ag, Pb, Zn, Cu, Co and Ni in some of...
Uranium geochemistry in geopressured-geothermal aquifers of the U.S. Gulf Coast
T. F. Kraemer, Y.K. Kharaka
1986, Geochimica et Cosmochimica Acta (50) 1233-1238
Formation water from U.S. Gulf Coast geopressured-geothermal sandstone aquifers has been analyzed to determine the geochemistry of uranium in these systems. Results of chemical analyses and chemical equilibrium modeling indicate the formation waters are in equilibrium with uraninite (UO2) and coffinite (USiO4). The 234U238U">234U238U activity ratios...
Nonlinear-regression groundwater flow modeling of a deep regional aquifer system
Richard L. Cooley, Leonard F. Konikow, Richard L. Naff
1986, Water Resources Research (22) 1759-1778
A nonlinear regression groundwater flow model, based on a Galerkin finite-element discretization, was used to analyze steady state two-dimensional groundwater flow in the areally extensive Madison aquifer in a 75,000 mi2 area of the Northern Great Plains. Regression parameters estimated include intrinsic permeabilities of the main aquifer and separate lineament zones,...
Recalibration and predictive reliability of a solute-transport model of an irrigated stream-aquifer system
M. Person, Leonard F. Konikow
1986, Journal of Hydrology (87) 145-165
A solute-transport model of an irrigated stream-aquifer system was recalibrated because of discrepancies between prior predictions of ground-water salinity trends during 1971-1982 and the observed outcome in February 1982. The original model was calibrated with a 1-year record of data collected during 1971-1972 in an 18-km reach of the Arkansas...
Isolation and detection of Giardia cysts from water using direct immunofluorescence
Stephen K. Sorenson, John L. Riggs, Peter D. Dileanis, Thomas J. Suk
1986, Water Resources Bulletin (22) 843-845
A water‐sampling apparatus used for the isolation and detection of Giardiacysts in water has been designed and tested. The sampling apparatus uses one of a variety of pumps or waterline pressure to move water through a filter. Two of the optional pumps are lightweight enough to make the apparatus portable and...
Effect of ground-water recharge on configuration of the water table beneath sand dunes and on seepage in lakes in the sandhills of Nebraska, U.S.A.
T. C. Winter
1986, Journal of Hydrology (86) 221-237
Analysis of water-level fluctuations in about 30 observation wells and 5 lakes in the Crescent Lake National Wildlife Refuge in the sandhills of Nebraska indicates water-table configuration beneath sand dunes in this area varies considerably, depending on the configuration of the topography of the dunes. If the topography of an...
Spectral reflectance of carbonatites and related alkalic igneous rocks: Selected samples from four North American localities
L. C. Rowan, M.J. Kingston, J.K. Crowley
1986, Economic Geology (81) 857-871
Laboratory spectral reflectance measurements were made in the 0.4- to 2.5-mu m wavelength range for samples collected from four North American carbonatite-alkalic igneous rock complexes. Alkalic rock spectra produced few absorption features; however, the carbonatites typically showed conspicuous carbonate, ferric and ferrous iron, and in some cases rare earth element...
Luminous phenomena and earthquakes in southern Washington
J.S. Derr, M.A. Persinger
1986, Experientia (42) 991-999
Luminous phenomena, mostly nocturnal lights, are associated with very small earthquakes in southern Washington state. The phenomena seem to be electrical in nature, related to earthquake lights, and tend to occur when the locus of earthquake activity moves across an active fault in an area of compressional stress. ?? 1986...
Development of labd cover and terrain databases for the Innoko National Wildlife Refuge, Alaska, using LANDSAT and digital terrain data
Carl J. Markon, Stephen S. Talbot
1986, Conference Paper, Technical Papers of the American Society of Photogrammetry, Fall Technical Meeting
Landsat-derived land cover maps and associated elevation, slope, and aspect class maps were produced for the Innoko National Wildlife Refuge (3,850,000 acres; 1,555,095 hectares) in northwestern Alaska. These maps and associated digital data products are being used by the U. S. Fish and Wildlife Service for wildlife management, research, and...
U. S. GEOLOGICAL SURVEY'S SIDE-LOOKING AIRBORNE RADAR PROGRAM: THE ALASKAN CONNECTION.
Allan N. Kover, John Edwin Jones, Stephen J. Gawarecki
1986, Conference Paper, Technical Papers of the American Society of Photogrammetry, Fall Technical Meeting
The U. S. Geological Survey (USGS) has become a major source of side-looking airborne radar (SLAR) data as a result of a Congressional mandate in 1980 to 'begin the use of side-looking airborne radar for topographic and geologic mapping, and geological resource surveys in promising areas, particularly Alaska. ' In...
USGS NATIONAL MAPPING PROGRAM IN ALASKA--A STATUS REPORT.
Bruce Y. Mckenzie, Lowell E. Starr
1986, Conference Paper, Technical Papers of the American Society of Photogrammetry, Fall Technical Meeting
The U. S. Geological Survey has been involved in mapping in Alaska since the late 1800's. The initial mapping projects were principally in support of geologic or hydrologic studies. In the late 1940's, responsibility for Alaska mapping was assigned to the Geological Survey's Rocky Mountain Mapping Center and a comprehensive...
The initial giant umbrella cloud of the May 18th, 1980, explosive eruption of Mount St. Helens
R. S. J. Sparks, J.G. Moore, C.J. Rice
1986, Journal of Volcanology and Geothermal Research (28) 257-274
The initial eruption column of May 18th, 1980 reached nearly 30 km altitude and released 1017 joules of thermal energy into the atmosphere in only a few minutes. Ascent of the cloud resulted in forced intrusion of a giant umbrella-shaped cloud between altitudes of 10 and 20 km at radial...
A soil catena on schist in northwestern California
D. C. Marron, J.H. Popenoe
1986, Geoderma (37) 307-324
Soil characteristics in a small steepland watershed underlain by schist in a rainy, tectonically active area in northwestern California show close associations with drainage-basin position and slope characteristics. Five soil-topography units based on these associations are defined in the study watershed. Spatial relationships of soil series, and patterns of soil...
Aqueous dissolution, solubilities and thermodynamic stabilities of common aluminosilicate clay minerals: Kaolinite and smectites
Howard M. May, D.G. Klnniburgh, P.A. Helmke, Melanie L. Jackson
1986, Geochimica et Cosmochimica Acta (50) 1667-1677
Determinations of the aqueous solubilities of kaolinite at pH 4, and of five smectite minerals in suspensions set between pH 5 and 8, were undertaken with mineral suspensions adjusted to approach equilibrium from over- and undersaturation. After 1,237 days, Dry Branch, Georgia kaolinite...
Origin of late Archean granite: geochemical evidence from the Vermilion Granitic Complex of northern Minnesota
W. C. Day, P.W. Weiblen
1986, Contributions to Mineralogy and Petrology (93) 283-296
The 2,700-Ma Vermilion Granitic Complex of northern Minnesota is a granite-migmatite terrane composed of supracrustal metasedimentary rocks, mafic rocks, tonalitic and granodioritic plutonic rocks, and granite. The metasedimentary rocks are predominantly graywacke, which has been regionally metamorphosed to garnet-sillimanite-muscovite-bearing biotite schist, and has locally undergone anatexis. The mafic rocks form...
Correlation between electron spin resonance spectra and oil yield in eastern oil shales
M. Choudhury, K.F. Rheams, J.W. Harrell Jr.
1986, Fuel (65) 1028-1029
Organic free radical spin concentrations were measured in 60 raw oil shale samples from north Alabama and south Tennessee and compared with Fischer assays and uranium concentrations. No correlation was found between spin concentration and oil yield for the complete set of samples. However, for a 13 sample set taken...
Effects of the 1906 Earthquake on the Bald Hill Outlet System, San Mateo County, California
Earl H. Pampeyan
1986, Bulletin of the Association of Engineering Geologists (23) 197-208
Following the earthquake of April 18, 1906, it was discovered that a brick forebay and other parts of the reservoir outlet system were in the slip zone of the San Andreas fault. The original outlet through which water was directed to San Francisco consisted of two tunnels joined at the...
A paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: Implications for CRM related to hydrothermal alteration
J.T. Hagstrum, C.M. Johnson
1986, Earth and Planetary Science Letters (78) 296-314
Paleomagnetic and rock magnetic data combined with stable isotope data from the middle Tertiary pluton along the Rio Hondo in northern New Mexico suggest that its magnetic remanence has both thermal (TRM) and high-temperature chemical (CRM) components. Oxygen isotope temperatures indicate...
Deformation of poorly consolidated sediment during shallow emplacement of a basalt sill, Coso Range, California
W. A. Duffield, C. R. Bacon, P.T. Delaney
1986, Bulletin of Volcanology (48) 97-107
A 150-m-long, wedge-shaped unit of folded and faulted marly siltstone crops out between undeformed sedimentary rocks on the north flank of the Coso Range, California. The several-meter-thick blunt end of this wedge abuts the north margin of a basaltic sill of comparable thickness. Chaotically deformed siltstone crops out locally at...