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Page 1529, results 38201 - 38225

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Deep structure and evolution of the Carolina Trough
D. R. Hutchinson, J. A. Grow, Kim D. Klitgord, B.A. Swift
1982, Book chapter, Studies in continental margin geology
Multichannel seismic-reflection data together with two-dimensional gravity and magnetic models suggest that the crustal structure off North Carolina consists of normal continental crust landward of the Brunswick magnetic anomaly (BMA), rift-stage crust in the 80-km-wide zone between the BMA and the East Coast magnetic anomaly (ECMA), and normal oceanic crust...
Ground-water temperature of the with application to ground-water-source heat pumps
Arthur L. Hodges Jr.
1982, Water-Resources Investigations Report 82-53
Ground-water temperature was measured during a one-year period (1980-81) in 20 wells in the Wyoming Quadrangle in central Delaware. Data from thermistors set at fixed depths in two wells were collected twice each week, and vertical temperature profiles of the remaining 18 wells were made monthly. Ground-water temperature at 8...
Digital model of predevelopment flow in the Tertiary limestone (Floridan) aquifer system in west-central Florida
Paul D. Ryder
1982, Water-Resources Investigations Report 81-54
A computer model was calibrated to approximate predevelopment flow conditions in a multilayered aquifer system in 10,600 square miles in west-central Floria. The lowermost aquifer, called the Floridan aquifer, is confined in most of the study area and consists of carbonate rocks ranging up to 1,300 feet thick. The Floridan...
Evaluation of AMOEBA: a spectral-spatial classification method
Susan K. Jenson, Thomas R. Loveland, J. Bryant
1982, Journal of Applied Photographic Engineering (8) 159-162
Muitispectral remotely sensed images have been treated as arbitrary multivariate spectral data for purposes of clustering and classifying. However, the spatial properties of image data can also be exploited. AMOEBA is a clustering and classification method that is based on a spatially derived model for image data. In an evaluation...
Regional thermal-inertia mapping from an experimental satellite
K. Watson
1982, Geophysics (47) 1681-1687
A new experimental satellite has provided, for the first time, thermal data that should be useful in reconnaissance geologic exploration. Thermal inertia, a property of geologic materials, can be mapped from these data by applying an algorithm that has been developed using a new thermal model. A simple registration procedure...
Photogrammetry of the Viking-Lander imagery.
S.S.C. Wu, F.J. Schafer
1982, Photogrammetric Engineering and Remote Sensing (48) 803-816
We have solved the problem of photogrammetric mapping from the Viking Lander photography in two ways: 1) by converting the azimuth and elevation scanning imagery to the equivalent of a frame picture by means of computerized rectification; and 2) by interfacing a high-speed, general-purpose computer to the AS-11A analytical plotter...
Modeling of tidal and residual circulation in San Francisco Bay, California
R. T. Cheng
1982, Conference Paper, Proceedings, Seminar on 2-D Flows
Several numerical models have been developed and implemented to simulate tidal and residual circulation in San Francisco Bay. Because of a broad distribution in time scales, hydrodynamic models must be formulated to account for the proper time and spatial scales which dominate the transport processes. A complete current survey of...
Chemical and light-stable isotope characteristics of waters from the Raft River geothermal area and environs, Cassia County, Idaho; Box Elder County, Utah
M. Nathenson, N.L. Nehring, E. G. Crosthwaite, R.S. Harmon, C. Janik, J. Borthwick
1982, Geothermics (11) 215-237
Chemical and light-stable isotope data are presented for water samples from the Raft River geothermal area and environs. On the basis of chemical character, as defined by a trilinear plot of per cent milliequivalents, and light-stable isotope data, the waters in the geothermal area can be divided into waters that...
Earthquake location in island arcs
E.R. Engdahl, J. W. Dewey, K. Fujita
1982, Physics of the Earth and Planetary Interiors (30) 145-156
A comprehensive data set of selected teleseismic P-wave arrivals and local-network P- and S-wave arrivals from large earthquakes occurring at all depths within a small section of the central Aleutians is used to examine the general problem of earthquake location in island arcs. Reference hypocenters for this special data set...
Recommended procedures and techniques for the petrographic description of bituminous coals
E. C. T. Chao, J.A. Minkin, C.L. Thompson
1982, International Journal of Coal Geology (2) 151-179
Modern coal petrology requires rapid and precise description of great numbers of coal core or bench samples in order to acquire the information required to understand and predict vertical and lateral variation of coal quality for correlation with coal-bed thickness, depositional environment, suitability for technological uses, etc. Procedures for coal...
A note on the Goodman Jack
H.S. Swolfs, J.D. Kibler
1982, Rock Mechanics Felsmechanik Mecanique des Roches (15) 57-66
A Note on the Goodman Jack. Reconnaissance experiments, performed to evaluate the practical utility of the hard-rock variety of the Goodman Jack 1, reveal that the Hustrulid-T* correction adequately reconciles the discrepancy between the measured and true deformation modulus of the rock mass in the range of 30 to50 gigapascals....
Implications of the Precambrian lineaments on the Red Sea tectonics based on Landsat study of northeast Sudan
F. Ahmed
1982, Global Tectonics and Metallogeny (1) 326-335
Lineament analysis of a Landsat Imagery mosaic (scale 1:1,000,000) of northeast Sugdan indicate significant curvilinear as well as rectilinear fracture patterns of possible Precambrian age.  Rectilinear features trend dominantly in N-S (± 10°), NNW and ENE, and less commonly in NW and EW directions.  The Precambrian fractures closely match, and...
International geomagnetic reference field 1980: a report by IAGA Division I working group.
N.W. Peddie
1982, Geophysical Journal of the Royal Astronomical Society (68) 265-268
Describes the recommendations of the working group, which suggested additions to IGRF because of the cumulative effect of the inevitable uncertainties in the secular variation models which had led to unacceptable inaccuracies in the IGRF by the late 1970's. The recommendations were accepted by the International Association of Geomagnetism and...
Evolution of continental crust and mantle heterogeneity: Evidence from Hf isotopes
Patchett P. Jonathan, O. Kouvo, C. E. Hedge, M. Tatsumoto
1982, Contributions to Mineralogy and Petrology (78) 279-297
We present initial 176Hf/177 Hf ratios for many samples of continental crust 3.7-0.3 Gy old. Results are based chiefly on zircons (1% Hf) and whole rocks: zircons are shown to be reliable carriers of essentially the initial Hf itself when properly chosen on the basis of U-Pb studies. Pre-3.0 Gy...
Benthic phosphorus regeneration in the Potomac River Estuary
E. Callender
1982, Hydrobiologia (91-92) 431-446
The flux of dissolved reactive phosphate from Potomac riverine and estuarine sediments is controlled by processes occurring at the water-sediment interface and within surficial sediment. In situ benthic fluxes (0.1 to 2.0 mmoles m-2 day-1) are generally five to ten times higher than calculated diffusive fluxes (0.020 to 0.30 mmoles...
Extension in the Rio Grande rift
L. Cordell
1982, Journal of Geophysical Research Solid Earth (87) 8561-8569
A positive gravity anomaly along the axis of the Rio Grande rift reflects a volume of anomalous mass added at the base of the crust and intruded into the crust. Part of this volume can be associated with vertical uplift of the crust. The remainder of this anomalous volume, plus...
Mineralogy and stable isotope geochemistry of hydrothermally altered oceanic rocks
D.S. Stakes, J. R. O’Neil
1982, Earth and Planetary Science Letters (57) 285-304
Mineralogical and isotopic variations observed in altered glassy and crystalline rocksfrom the East Pacific Rise and the Mid-Atlantic Ridge provide information about the temperatures of alteration and seawater/rock ratios for various hydrothermal regimes within the oceanic crust. A systematic increase in alteration temperature is evident for the glassy rocksin the...
Permafrost, heat flow, and the geothermal regime at Prudhoe Bay, Alaska
A.H. Lachenbruch, J.H. Sass, B.V. Marshall, T. H. Moses Jr.
1982, Journal of Geophysical Research Solid Earth (87) 9301-9316
Temperature measurements through permafrost in the oil field at Prudhoe Bay, Alaska, combined with laboratory measurements of the thermal conductivity of drill cuttings permit an evaluation of in situ thermal properties and an understanding of the general factors that control the geothermal regime. A sharp contrast in temperature gradient at...
The modified polyconic projection for the IMW
John P. Snyder
1982, Cartographica: The International Journal for Geographic Information and Geovisualization (19) 31-43
The modified Polyconic map projection designed by Lallemand and adopted for the International Map of the World between 1909 and 1962 has two meridians and two parallels which are true to scale. Constructed geometrically in the past, forward and inverse coordinate transformations may be calculated analytically in order to transfer...
Upper crustal structure of the Mount Hood, Oregon, region as revealed by time term analysis
W.M. Kohler, J. H. Healy, S.S. Wegener
1982, Journal of Geophysical Research Solid Earth (87) 339-355
Seismic refraction data with a dense areal distribution were collected to study the seismic structure of Mount Hood and the surrounding region. This area is typical of Cascade volcanoes and is geologically quite complex. The prime goals of this project were to search for velocity variations in the upper crustal...
Stratigraphic reference section for Georges Bank Basin - Depositional model for New England passive margin.
C. Wylie Poag
1982, American Association of Petroleum Geologists Bulletin (66) 1021-1041
A multichannel seismic reflection profile (U.S. Geological Survey line 19), calibrated with the COST G-1, COST G-2, and Shell Mohican I-100 wells, and seismic-sequence analysis shows that the chronostratigraphic and lithostratigraphic units and depositional history of the Georges Bank basin are similar to those of the Scotian basin. Carbonate rocks...
Huge landslide blocks in the growth of piton de la fournaise, La réunion, and Kilauea volcano, Hawaii
Wendell A. Duffield, Laurent Stieltjes, Jacques Varet
1982, Journal of Volcanology and Geothermal Research (12) 147-160
Piton de la Fournaise, on the island of La Réunion, and Kilauea volcano, on the island of Hawaii, are active, basaltic shield volcanoes growing on the flanks of much larger shield volcanoes in intraplate tectonic environments. Past studies have shown that the average rate of magma production and the chemistry...
Mineralogy and geochemistry of Fe-Ti oxide and apatite (nelsonite) deposits and evaluation of the liquid immiscibility hypothesis.
A. Kolker
1982, Economic Geology (77) 1146-1158
Modal mineralogy determined for 32 Fe-Ti oxide and apatite rocks from localities in Virginia, New York, Quebec, Norway, and Sweden largely supports the 2:1 oxide:apatite ratio suggested as a eutectic mixture by Philpotts (1967). A fairly consistent suite of accessory minerals, including biotite, clinoamphibole, spinel, zircon, and sulfides, is present....