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Page 4953, results 123801 - 123825

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Geochemical evidence for a Brooks Range mineral belt, Alaska
S.P. Marsh, J. B. Cathrall
1981, Journal of Geochemical Exploration (15) 367-380
Geochemical studies in the central Brooks Range, Alaska, delineate a regional, structurally controlled mineral belt in east—west-trending metamorphic rocks and adjacent metasedimentary rocks. The mineral belt extends eastward from the Ambler River quadrangle to the Chandalar and Philip Smith quadrangles, Alaska, from 147° to 156°W. longitude, a distance of more...
Quaternary and geodetically measured crustal movements in the Tokai District, Central Honshu, Japan
W. Thatcher, T. Matsuda
1981, Journal of Geophysical Research Solid Earth (86) 9237-9247
Geodetic measurements made in this century demonstrate that modern movements correlate well with deformation that has occurred during the past 2 m.y. Both show effects of subduction and of the Quaternary collision of Izu Peninsula with Central Honshu. Westward from Suruga Bay, deformation is greatest near the coast, decreases markedly...
Potential for geophysical experiments in large scale tests
James H. Dieterich
1981, Geophysical Research Letters (8) 653-656
Potential research applications for large-specimen geophysical experiments include measurements of scale dependence of physical parameters and examination of interactions with heterogeneities, especially flaws such as cracks. In addition, increased specimen size provides opportunities for improved recording resolution and greater control of experimental variables. Large-scale experiments using...
Back-extraction of trace elements from organometallic-halide extracts for determination by flameless atomic absorption spectrometry
J. Robert Clark, John G. Viets
1981, Analytical Chemistry (53) 65-70
The Methyl isobutyl ketone-Amine synerGistic Iodkte Complex (MAGIC) extraction system offers the advantage that a large number of trace elements can be rapidly determined with a single sample preparation procedure. However, many of the elements extracted by the MAGIC system form volatile organometallic halide salts when the organic extract is...
A transient laboratory method for determining the hydraulic properties of 'tight' rocks-I. Theory
P. A. Hsieh, J.V. Tracy, C. E. Neuzil, J.D. Bredehoeft, Stephen E. Silliman
1981, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts (18) 245-252
Transient pulse testing has been employed increasingly in the laboratory to measure the hydraulic properties of rock samples with low permeability. Several investigators have proposed a mathematical model in terms of an initial-boundary value problem to describe fluid flow in a transient pulse test. However, the solution of this problem...
Geologic controls of uranium mineralization in the Tallahassee Creek uranium district, Fremont County, Colorado.
K. A. Dickinson
1981, Mountain Geologist (18) 88-95
Two important orebodies have been defined by drilling in the Tallahassee Creek uranium district, Fremont County, Colorado, namely the Hansen and the Picnic Tree. Host rocks are respectively the upper Eocene Echo park Alluvium, and the lower Oligocene Tallahassee Creek Conglomerate. Average ore grade is about 0.08% U3O8. The principal...
An examination of techniques for reformatting digital cartographic data. Part 2: The vector-to raster process.
Donna J. Peuquet
1981, Cartographica: The International Journal for Geographic Information and Geovisualization (18) 21-33
Current graphic devices suitable for high-speed computer input and output of cartographic data are tending more and more to be raster-oriented, such as the rotating drum scanner and the color raster display. However, the majority of commonly used manipulative techniques in computer-assisted cartography and automated spatial data handling continue to...
Ne matrix spectra of the sym-C6Br3F3+ radical cation
V.E. Bondybey, T.J. Sears, T.A. Miller, C. Vaughn, J.H. English, R.S. Shiley
1981, Chemical Physics (61) 9-16
The electronic absorption and laser excited, wavelength resolved fluorescence spectra of the title cation have been observed in solid Ne matrix and vibrationally analysed. The vibrational structure of the excited B2A2??? state shows close similarity to the parent compound. The X2E??? ground state structure is strongly perturbed and irregular owing...
The logic of multispectral classification and mapping of land
Charles J. Robinove
1981, Remote Sensing of Environment (11) 231-244
The use of multispectral reflectance data as surrogates for land attributes must be done within strict rules of logic and with a recognition of judgmental factors such as the use of a priori or a posteriori classification schemes. The naming and describing of spectral classes as surrogates of information classes...
Improved spectrophotometric cell for hydrothermal solutions
N.J. Susak, D.A. Crerar, T.C. Forseman, J.L. Haas Jr.
1981, Review of Scientific Instruments (52) 428-431
A simple, inexpensive spectrophotometric cell was designed for use with aqueous solutions for which temperature is a maximum of 325??C and pressure, 28 MPa. The cell has an internal volume of 5 ml and a path length of 1.31 cm. Each furnace assembly is 120 mm in diameter ?? 150...
K-Ar ages on intrusive and altered zones in the Chignik and Sutwik Island quadrangles: A section in The United States Geological Survey in Alaska: Accomplishments during 1979
Frederic H. Wilson
1981, Report, The United States Geological Survey in Alaska: Accomplishments during 1979 (Circular 823-B)
Continued K-Ar dating of intrusive rocks and hydrothermal alteration zones in the Chignik and Sutwik Island quadrangles of the Alaska Peninsula, supplemental to that by Wilson, Detterman, and Silberman (1978) and Wilson (1978), has refined our knowledge of the ages of the igneous rocks and clarified relations between altered zones...
Water type and suitability of Oklahoma surface waters for public supply and irrigation, Part 3: Canadian, North Canadian, and deep fork river basins through 1979
Jerry D. Stoner
1981, Water-Resources Investigations Report 81-80
Water-quality data through 1979 in the Canadian, North Canadian, and Deep Fork River basins within Oklahoma were examined for water type and suitability for public water supply and irrigation use. Of 105 stations with available data, 47 stations or 45 percent were considered to have sufficient data for analysis. The...
The occurrence of chlorine in serpentine minerals
Y. Miura, J. Rucklidge, Gordon L. Nord Jr.
1981, Contributions to Mineralogy and Petrology (76) 17-23
Partially serpentinized dunites containing small amounts of Chlorine (< 0.5%) from Dumont, Quebec, and Horoman, Hokkaido, Japan, and one containing less than 0.05% Chlorine from Higashi-Akaishi-Yama, Ehime, Japan have been examined using the electron probe microanalyzer and scanning transmission electron microscope with X-ray analytical capabilities. Chlorine was found together with...
Munsell color value as related to organic carbon in Devonian shale of Appalachian basin
John W. Hosterman, Sallie I. Whitlow
1981, American Association of Petroleum Geologists Bulletin (65) 333-335
Comparison of Munsell color value with organic carbon content of 880 samples from 50 drill holes in the Appalachian basin shows that a power curve is the best fit for the data. A color value below 3 to 3.5 indicates the presence of organic carbon but is meaningless in determining...
Aseismic uplift in California
Robert O. Castle, Michael R. Elliot, Thomas D. Gilmore, Robert K. Mark, Evelyn B. Newman, John C. Tinsley III, D.D. Jackson, W.B. Lee, C.-C. Liu
1981, Science (213) 246-247
We disagree with several of the arguments cited by Jackson et al. in support of their view that "the inference of wide-spread aseismic uplift in southern California is not justified" (1). Specifically, the striking correlation shown in figure 1 of Jackson et al. (1) is an artifact of the construction,...
Cretaceous Arctic silicoflagellates
D. Bukry
1981, Geo-Marine Letters (1) 57-63
Cretaceous silicoflagellate assemblages from Arctic Ocean USGS Core 437 show Vallacerta siderea the most abundant species; most species of Lyramula disappear halfway up the core; only L. burchardae, n. sp., persists into the upper sections. These occurrences are untypical of the few documented Cretaceous assemblages from other areas. A Campanian...
13C 12C exchange between calcite and graphite: A possible thermometer in Grenville marbles
J.W. Valley, J. R. O’Neil
1981, Geochimica et Cosmochimica Acta (45) 411-419
The fractionation of 13C between calcite and graphite, Δ(Cc-Gr). is consistently small (2.6–4.8 permil) in 34 assemblages from upper amphibolite- and granulite-facies marbles of the Grenville Province. In 25 samples from the Adirondack Mountains, New York, it decreases regularly with increasing metamorphic temperature. The fractionations are independent of absolute δ13C values...
Stratigraphy of the Caloris basin, Mercury
J.F. McCauley, J. E. Guest, G. G. Schaber, N.J. Trask, R. Greeley
1981, Icarus (47) 184-202
Caloris basin, Mercury’s youngest large impact basin, is filled by volcanic plains that are spectrally distinct from surrounding material. Post-plains impact craters of a variety of sizes populate the basin interior, and the spectra of the material they have...
Mercury in the muscle tissue of fish from three northern Maine lakes
J.J. Akielaszek, T.A. Haines
1981, Bulletin of Environmental Contamination and Toxicology (27) 201-208
There is evidence that fish in Canadian wilderness areas exhibit elevated mercury levels because of the oligotrophic nature of the lakes they inhabit (BROUZES et al. 1977). D'ITRI et al. (1971) reported higher levels of mercury in trout from oligotrophic waters than in trout from eutrophic waters in unpolluted areas....
Morphology and processes associated with the accumulation of the fine-grained sediment deposit on the southern New England shelf
David C. Twichell, Charles E. McClennen, Bradford Butman
1981, Journal of Sedimentary Petrology (51) 269-280
A 13,000 km2 area of the southern New England Continental Shelf which is covered by anomalously fine-grained sediment has been surveyed by means of high-resolution, seismic-reflection and side-scan sonar techniques to map its morphology and structure, and a near-bottom instrument system contributed to understanding present activity of the deposit. Seismic-reflection...
Aeromagnetic and radio echo ice-sounding measurements over the Dufek intrusion, Antarctica
John C. Behrendt, D.J. Drewry, E. Jankowski, M. S. Grim
1981, Journal of Geophysical Research Solid Earth (86) 3014-3020
A combined aeromagnetic and radio echo ice-sounding survey (4200 km of traverse) made in 1978 in Antarctica over the Dufek layered mafic intrusion of Jurassic age suggests a minimum area of about 50,000 km2, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and...
Upper Oligocene evaporites in basin fill of Sevier Desert region, western Utah
D. A. Lindsey, Richard K. Glanzman, Charles W. Naeser, Douglas J. Nichols
1981, American Association of Petroleum Geologists Bulletin (65) 251-260
The basin fill beneath the Sevier Desert of western Utah contains evaporites that were deposited in a broad closed basin. All of the basin fill penetrated by the Gulf Oil 1 Gronning contains abundant volcanic detritus and its alteration products of Cenozoic age. Fission-track dating of tuffaceous sandstone yields ages...