Russell C. Evarts, Peter Schiffman
1983, American Journal of Science (283) 289-340
No abstract available....
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Publication Extents
Not all publications have extents, not all extents are completely accurateG. B. Dalrymple
1983, Journal of Geological Education (31) 124-133
Thomas G. Barnes, Emeritus Professor of Physics at the University of Texas, El Paso, and a creationist, argues that the geomagnetic field was created by unknown processes at the time of creation of the earth and has been decaying irreversibly and exponentially, with a half-life of about 1400 years,...
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...
W. E. Scott, W.D. McCoy, R. R. Shroba, M. Rubin
1983, Quaternary Research (20) 261-285
A substantially modified history of the last two cycles of Lake Bonneville is proposed. The Bonneville lake cycle began prior to 26,000 yr B.P.; the lake reached the Bonneville shoreline about 16,000 yr B.P. Poor dating control limits our knowledge of the timing of subsequent events. Lake level was maintained...
J.A. Perkins, J.D. Sims
1983, Quaternary Research (20) 308-321
The thickness of varves in the sediments of Skilak Lake, Alaska, are correlated with the mean annual temperature (r = 0.574), inversely correlated with the mean annual cumulative snowfall (r = -0.794), and not correlated with the mean annual precipitation (r = 0.202) of the southern Alaska climatological division for...
J.W. Harden, E. M. Taylor
1983, Quaternary Research (20) 342-359
A new quantitative Soil Development Index based on field data has been applied to chronosequences formed under different climatic regimes. The four soil chronosequences, developed primarily on sandy deposits, have some numeric age control and are located in xeric-inland (Merced, Calif.), xeric-coastal (Ventura, Calif.), aridic (Las Cruces, N. Mex.), and...
Stephen A. Wilson, Carol A. Gent
1983, Analytica Chimica Acta (148) 299-303
Samples of silicate rocks are prepared by sodium carbonate fusion and then treated by ion chromatography. The method was tested for geological standards with chloride concentration between 0.003 and 3%. Observed chloride concentrations comparedd favorably with literature values. The relative standard deviation and detection limit for the method were 8%...
K.A. Kvenvolden, J.W. Harbaugh
1983, Marine Environmental Research (10) 223-243
Previous estimates of the world-wide input of oil to the marine environment by natural seeps ranged from 0??2 to 6??0 million (metric) tonnes per year with a 'best estimate' of 0??6 million tonnes per year. Based on considerations of the availability of oil for seepage from the world's known and...
R.J. Rosenbauer, J. L. Bischoff, A. S. Radtke
1983, Economic Geology (78) 1701-1710
Separate experiments at 350 degrees C and 500 bars at a rock/fluid ratio of 1/10. Illite, dolomite, and quartz amounting to 67 percent of the original graywacke, were converted to albite and smectite. The rock gained Na and released Ca, K, heavy metals, and CO 2 to solution. In sharp contrast, the...
Samuel N. Luoma, J.A. Davis
1983, Marine Chemistry (12) 159-181
The fate of particulate-bound metals is of particular importance in estuaries because major biological energy flows involve consumption of detrital particles. The biological impact of particulate-bound metals is strongly influenced by the partitioning of metals among sediment components at the oxidized sediment-water interface. Adequate methods for directly measuring this partitioning...
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...
R. A. Loney, G. R. Himmelberg
1983, Journal of Petrology (24) 377-423
The middle Tertiary La Perouse gabbro intrusion occurs in a Mesozoic metamorphic terrane (Chugach terrane) in the Fairweather Range, southeastern Alaska. The intrusion is 12 km wide and 27 km long, and has an exposed cumulate layering thickness of about 6000 m. The contact consists of biotite and hornblende...
R. J. McLaughlin, K. R. Lajoie, D. H. Sorg, S.D. Morrison, J. A. Wolfe
1983, Geology (11) 35-39
An uplifted wave-cut marine platform eroded across bedrock of the Franciscan Complex at Point Delgada, northern California, is overlain by 0.5 to 5 m of wave-worked pea gravel, which is in turn directly overlain by fluvial gravel and silt deposited as alluvial fans....
Richard A. Sheppard, Arthur J. Gude III
1983, Clays and Clay Minerals (31) 57-59
Harmotome, probably the most common of the barium-rich zeolites, has been reported from a variety of metamorphic and igneous rocks throughout the world (Deer et al., 1963). Harmotome, however, seems to be a rare authigenic constituent in sedimentary rocks, and its most common occurrence apparently is in deep-sea sediments where...
W.M. Alley
1983, Ground Water (21) 456-464
Vast deposits of oil shale are contained in the Piceance basin in northwestern Colorado. The basin may contain as much as 40 million acre-feet of stored water associated with these deposits, much of which may have to be drained for mining. Yet, most analyses of...
R. M. Forester
1983, Geology (11) 435-438
Nonmarine ostracode species are indicative of the physical and chemical nature of lacustrine environments. Although salinity has traditionally been regarded as one of the more important parameters that affect the occurrence patterns of lacustrine ostracodes, examination of the solute composition and salinities of...
G. P. Landis
1983, Chemical Geology (41) 91-94
An isotopically homogeneous calcite, Harding Iceland Spar (HIS), having 6180 = +11.78 ± 0.07‰ (= +22.15‰ for CO2) and δ13C = −4.80 ± 0.02‰, has been prepared in quantities suitable for use as a working standard in mass spectrometric analysis. The isotopic values are well-suited for analysis of minerals of hydrothermal...
Gordon L. Nord Jr., M.-V. Wandless
1983, Journal of Geophysical Research Solid Earth (88) A645-A657
Lunar breccia 62236 contains large lithic fragments of troctolite, norite, and anorthosite. The mafic phases, olivine, inverted pigeonite, and augite, fill interstitial areas between larger plagioclases and appear to be cumulate phases with extensive adcumulus growth. Pyroxene compositional homogeneity indicates that cation exchange during cooling was limited to an area...
Richard L. Cooley
1983, Water Resources Research (19) 662-676
This paper investigates factors influencing the degree of improvement in estimates of parameters of a nonlinear regression groundwater flow model by incorporating prior information of unknown reliability. Consideration of expected behavior of the regression solutions and results of a hypothetical modeling problem lead to several general conclusions. First, if the...
J. W. Cole, K. V. Cashman, P.C. Rankin
1983, Chemical Geology (38) 255-274
Two types of basalt (a high-Al basalt associated with the rhyolitic centres north of Taupo and a "low-Al" basalt erupted from Red Crater, Tongariro Volcanic Centre) and five types of andesite (labradorite andesite, labradorite-pyroxene andesite, hornblende andesite, pyroxene low-Si andesite and olivine andesite/low-Si andesite) occur in the Taupo Volcanic Zone...
J.A. Curiale, W.E. Harrison, G. Smith
1983, Geochimica et Cosmochimica Acta (47) 517-523
Solid bitumens (grahamite and impsonite) of southeastern Oklahoma have been shown to originate from near-surface alteration of crude oil (Curiale, 1981; Curiale and Harrison, 1981). Pyrolysis of these solids has been employed to compare the sterane distribution of geographically proximate oils to that of the bitumens. The ratio of rearranged...
Scott A. Hatch, Martha A. Hatch
1983, Wildfowl (34) 130-136
Recently we discovered that a small form of the Canada Goose Branta canadensis breeds on Kaliktagik Island, one of the Semidi Islands, about 80 km south of the Alaska Peninsula near longitude 157°W (Figure 1). The unexpected occurrence of geese on this oceanic island and the possibility that they are...
Diane E. Moore, C.A. Morrow, J.D. Byerlee
1983, Geochimica et Cosmochimica Acta (47) 445-453
Distilled water was passed at a low rate down a temperature gradient through cylinders of Barre and Westerly Granite. Temperatures ranged from 80–100°C at the outer edges of the cylinders to 250–300°C in central, drilled holes which housed the heating coils. The measured permeabilities of the granite cylinders decreased by...
J.G. Crock, F.E. Lichte, Paul H. Briggs
1983, Geostandards Newsletter (7) 335-340
Two new geologic reference materials, issued by the National Bureau of Standards as standard reference materials, have been analyzed by a precise, accurate, and rapid method of analysis for their element content. The described procedure uses a multi‐acid, low temperature digestion in a closed teflon vessel, followed by the simultaneous...
D.J. DePaolo, F.T. Kyte, B.D. Marshall, J. R. O’Neil, J. Smit
1983, Earth and Planetary Science Letters (64) 356-373
Isotopic ratios and trace element abundances were measured on samples of Ir-enriched clay at the Cretaceous-Tertiary boundary, and in carbonate and marl from 5 cm below and 3 cm above the boundary. Samples were leached with acetic acid to remove carbonate, and with hydrochloric acid. Leachates and residues were measured....