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Page 4746, results 118626 - 118650

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Investigation of internal friction in fused quartz, steel, Plexiglass, and Westerly granite from 0.01 to 1.00 Hertz at 10-8 to 10-7 strain amplitude
Hsi-Ping Liu, L. Peselnick
1983, Journal of Geophysical Research Solid Earth (88) 2367-2379
A detailed evaluation on the method of internal friction measurement by the stress-strain hysteresis loop method from 0.01 to 1 Hz at 10−8 to 10−7 strain amplitude and 23.9°C is presented. Significant systematic errors in relative phase measurement can result from convex end surfaces of the sample and stress sensor and from...
Large partition coefficients for trace elements in high-silica rhyolites
G. Mahood, W. Hildreth
1983, Geochimica et Cosmochimica Acta (47) 11-30
The partitioning of 25 trace elements between high-silica rhyolitic glass and unzoned phenocrysts of potassic and sodic sanidine, biotite, augite, ferrohedenbergite, hypersthene, fayalite, titanomagnetite, ilmenite, zircon, and allanite has been determined by INAA on suites of samples from the mildly peralkaline...
Characteristic analysis-1981: Final program and a possible discovery
R.B. McCammon, J.M. Botbol, R. Sinding-Larsen, R. W. Bowen
1983, Journal of the International Association for Mathematical Geology (15) 59-83
The latest ornewest version of thecharacteristicanalysis (NCHARAN)computer program offers the exploration geologist a wide variety of options for integrating regionalized multivariate data. The options include the selection of regional cells for characterizing deposit models, the selection of variables that constitute the models, and the choice of logical combinations of variables...
Distribution, abundance and carbon isotopic composition of gaseous hydrocarbons in Big Soda Lake, Nevada: An alkaline, meromictic lake
R.S. Oremland, D.J. Des Marais
1983, Geochimica et Cosmochimica Acta (47) 2107-2114
Distribution and isotopic composition (δ13C) of low molecular weight hydrocarbon gases were studied in Big Soda Lake (depth = 64 m), an alkaline, meromictic lake with permanently anoxic bottom waters. Methane increased with depth in the anoxic mixolimnion (depth = 20–35 m), reached uniform concentrations (55 μM/l) in the monimolimnion...
The contribution of humic substances to the acidity of colored natural waters
B.G. Oliver, E.M. Thurman, Ronald L. Malcolm
1983, Geochimica et Cosmochimica Acta (47) 2031-2035
An operationally defined carboxyl content of humic substances extracted from rivers, streams, lakes, wetlands, and groundwaters throughout the United States and Canada is reported. Despite the diversity of the samples, only small variations were observed in this humic carboxyl content. The dissociation behavior of two combined fulvic/humic acid extracts was...
Nontronite from a low-temperature hydrothermal system on the Juan de Fuca Ridge
R. Murnane, D.A. Clague
1983, Earth and Planetary Science Letters (65) 343-352
A deposit of Fe-rich, Al-poor, hydrothermal nontronite was recovered from the Juan de Fuca Ridge. Analyses show the deposit to be mineralogically and chemically similar to nontronite described at other oceanic localities. The deposit is located near the tip of a...
Plutonic rocks of Jurassic age in the Alaska-Aleutian Range batholith: Ghemical variation and polarity
B.I. Reed, A.T. Miesch, M. A. Lanphere
1983, Geological Society of America Bulletin (94) 1232-1240
Plutonic rocks of Jurassic age exposed on the eastern, or Pacific, side of the Alaska–Aleutian Range batholith represent the roots of a magmatic arc generally considered to have been generated in response to northwest-directed subduction. These rocks form a compositionally continuous calc-alkaline suite...
A teleseismic analysis of the New Brunswick earthquake of January 9, 1982
G. L. Choy, J. Boatwright, J. W. Dewey, S.A. Sipkin
1983, Journal of Geophysical Research Solid Earth (88) 2199-2212
The analysis of the New Brunswick earthquake of January 9, 1982, has important implications for the evaluation of seismic hazards in eastern North America. Although moderate in size (mb 5.7), it was well-recorded teleseismically. Source characteristics of this earthquake have been determined from analysis of data that were digitally recorded by...
A short-pulse electromagnetic transponder for hole-to-hole use
David L. Wright, Raymond D. Watts, Erik Bramsoe
1983, IEEE Transactions on Geoscience and Remote Sensing (GE-22) 720-725
We have made hole-to-hole observations through nearly 20 m of granite using an electromagnetic transponder (an active reflector) in one borehole and a single-hole short-pulse radar in another. We found that the transponder is inexpensive, operationally simple, and effective in extending the capability of a short-pulse borehole radar system to...
The saltwater-freshwater interface in the Tertiary limestone aquifer, southeast Atlantic outer-continental shelf of the U.S.A.
R.H. Johnston
1983, Journal of Hydrology (61) 239-249
Hydrologic testing in an offshore oil well abandoned by Tenneco, Inc., determined the position of the saltwater-freshwater interface in Tertiary limestones underlying the Florida-Georgia continental shelf of the U.S.A. Previous drilling (JOIDES and U.S.G.S. AMCOR projects) established the existence of freshwater far offshore in this area. At the Tenneco well...
Serological comparison of selected isolates of Aeromonas salmonicida ssp. Salmonicida
G.B. Hahnel, R. W. Gould, E.S. Boatman
1983, Journal of Fish Diseases (6) 1-11
Eight isolates of Acronionus salmonicida ssp. salmonicida were collected during furunculosis epizootics in North American Pacific coast states and provinces. Both virulent and avirulent forms of each isolate, confirmed by challenge and electron microscopy, were examined. Serological comparisons by cross-absorption agglutination tests revealed no serological differences between isolates. Using...
The geology of the terrestrial planets.
M. H. Carr
1983, Reviews of Geophysics and Space Physics (21) 160-172
During the last four years our knowledge of the geology of the terrestrial planets has advanced rapidly. The advances are particularly noticeable for Venus and Mars. Improved understanding of Venus has come largely from the Pioneer Venus mission. The period was also one of almost continuous data gathering for Mars...
Explosive activity associated with the growth of volcanic domes
C. G. Newhall, W.G. Melson
1983, Journal of Volcanology and Geothermal Research (17) 111-131
Domes offer unique opportunities to measure or infer the characteristics of magmas that, at domes and elsewhere, control explosive activity. A review of explosive activity associated with historical dome growth shows that: 1. (1) explosive activity has occurred in close association with nearly all historical dome growth; 2. (2) whole-rock...
Laboratory investigations of steam flow in a porous medium
W.N. Herkelrath, A.F. Moench, II C. F. O’Neal C. F.
1983, Water Resources Research (19) 931-937
Experiments were carried out in the laboratory to test a theory of transient flow of pure steam in a uniform porous medium. This theory is used in modeling pressure transient behavior in vapor dominated geothermal systems. Transient, superheated steam flow experiments were run by bringing a cylinder of porous material...
Old Crow tephra: A new late Pleistocene stratigraphic marker across north-central Alaska and western Yukon Territory
J.A. Westgate, T. D. Hamilton, M.P. Gorton
1983, Quaternary Research (19) 38-54
Old Crow tephra is the first extensive Pleistocene tephra unit to be documented in the northwestern part of North America. It has a calc-alkaline dacitic composition with abundant pyroxene, plagioclase, and FeTi oxides, and minor hornblende, biotite, apatite, and zircon. Thin, clear, bubble-wall fragments are the dominant type of glass...
Geochemistry of diverse basalt types from Loihi Seamount, Hawaii: Petrogenetic implications
F.A. Frey, D.A. Clague
1983, Earth and Planetary Science Letters (66) 337-355
The wide variety of basalt types, tholeiitic to basanite, dredged from Loihi Seamount have minor and trace element abundances that are characteristic of subaerial Hawaiian basalts, thereby confirming that Loihi Seamount is a manifestation of the Hawaiian “hot spot”. Within the Loihi sample suite there are well-defined positive correlations among...
Chryse Basin channels: low-gradients and ponded flows.
Baerbel K. Lucchitta, H.M. Ferguson
1983, Journal of Geophysical Research (88) A553-A568
Gradients on the floors of the Martian outflow channels that are derived from radar-elevation profiles across Lunae Planum and Chryse Basin have much lower values than those obtained from the U.S. Geological Survey's topographic map. Whereas the gradients of Maja and Ares Valles are similar to those of the catastrophic...
Structure, burial history, and petroleum potential of frontal thrust belt and adjacent foreland, southwest Montana
W. J. Perry Jr., B. R. Wardlaw, N. H. Bostick, E. K. Maughan
1983, American Association of Petroleum Geologists Bulletin (67) 725-743
The frontal thrust belt in the Lima area of southwestern Montana consists of blind (nonsurfacing) thrusts of the Lima thrust system beneath the Lima anticline and the Tendoy thrust sheet to the west. The Tendoy sheet involves Mississippian through Cretaceous rocks of the southwest-plunging nose of the Mesozoic Blacktail-Snowcrest uplift...
Generalized adjustment by least squares ( GALS).
A.A. Elassal
1983, Photogrammetric Engineering and Remote Sensing (49) 201-206
The least-squares principle is universally accepted as the basis for adjustment procedures in the allied fields of geodesy, photogrammetry and surveying. A prototype software package for Generalized Adjustment by Least Squares (GALS) is described. The package is designed to perform all least-squares-related functions in a typical adjustment program. GALS is...
Late Holocene ice wedges near Fairbanks, Alaska, USA: Environmental setting and history of growth
T. D. Hamilton, T. A. Ager, S.W. Robinson
1983, Arctic and Alpine Research (15) 157-168
Test trenches excavated into muskeg near Fairbanks in 1969 exposed a polygonal network of active ice wedges. The wedges occur in peat that has accumulated since about 3500 yr BP and have grown episodically as the permafrost table fluctuated in response to fires, other local site conditions and perhaps regional...
STABLE ISOTOPE GEOCHEMISTRY OF THERMAL FLUIDS FROM LASSEN VOLCANIC NATIONAL PARK, CALIFORNIA.
Cathy J. Janik, Nancy L. Nehring, Alfred H. Truesdell
1983, Conference Paper, Transactions - Geothermal Resources Council
In the Lassen vapor-dominated geothermal system, surface manifestations of thermal fluids at high elevations (1800-2500 m) include superheated and drowned fumaroles, steam-heated acid-sulfate hot springs, and low-chloride bicarbonate springs. Neutral high-chloride hot water discharges at lower elevations. Deuterium and oxygen-18 data establish genetic connections between these fluids and with local...
Seabirds between Alaska and Hawaii
Patrick J. Gould
1983, The Condor (85) 286-291
Seabirds were observed between Alaska and Hawaii along 158°W longitude from 24 October to 6 November 1976. Their distributions and abundances corresponded remarkably well to oceanographic regions. Indices of seabird density dropped in a series of plateaus from 44 birds/km2 in the Alaska Current System to less than 1 bird/km2...