R. B. Taylor, T. A. Steven
1983, Economic Geology (78) 1268-1270
No abstract available....
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Publication Extents
Not all publications have extents, not all extents are completely accurateR. 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...
A. Zaporozec
1983, Environmental Geology (5) 35-38
In recent years, considerable interest has been expressed in the nitrate content of water supplies. The most notable toxic effect of nitrate is infant methemoglobinemia. The risk of this disease increases significantly at nitrate-nitrogen levels exceeding 10 mg/l. For this reason, this concentration has been established as a limit for...
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...
Thomas J. Casadevall, Richard W. Hazlett
1983, Journal of Volcanology and Geothermal Research (16) 173-188
Active thermal areas are concentrated in three areas on Mauna Loa and three areas on Kilauea. High-temperature fumaroles (115-362°C) on Mauna Loa are restricted to the summit caldera, whereas high-temperature fumaroles on Kilauea are found in the upper East Rift Zone (Mauna Ulu summit fumaroles, 562°C), middle East Rift Zone...
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...
S. G. Hughes, G. L. Rumsey, M.C. Nesheim
1983, Comparative Biochemistry and Physiology, Part B: Comparative Biochemistry (76) 429-431
1. The enzyme branched-chain amino acid aminotransferase (BCAT) was found in five tissues of fingerling lake trout, Salvelinus namaycush, (listed in order of decreasing tissue specific activity): posterior kidney, skeletal muscle, gill, liver, and anterior kidney.2. This pattern is consistent with that found in other animals.3. The results of this...
Hans Schouten, Kim D. Klitgord
1983, Nature (303) 549-550
[No abstract available]...
J. E. Cloern, B.E. Cole, R.S. Oremland
1983, Hydrobiologia (105) 195-206
Big Soda Lake is an alkaline, saline lake with a permanent chemocline at 34.5 m and a mixolimnion that undergoes seasonal changes in temperature structure. During the period of thermal stratification, from summer through fall, the epilimnion has low concentrations of dissolved inorganic nutrients (N, Si) and CH4, and low...
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...
J.L. Bada, J.R. Cronin, M.-S. Ho, K.A. Kvenvolden, J.G. Lawless, S.L. Miller, John Oro, S. Steinberg
1983, Nature (301) 494-496
In analyses of extracts from the Murchison meteorite (a carbonaceous chondrite), Engel and Nagy1 reported an excess of L-enantiomers for several protein amino acids but found that the non-protein amino acids were racemic. They suggested that the excess of L-isomers might have resulted from an asymmetric synthesis or decomposition. Their...
R. O. Castle, B.W. Brown Jr., T.D. Gilmore, R. K. Mark, R. C. Wilson
1983, Geophysical Research Letters (10) 1081-1084
Appraisals of the two levelings that formed the southern California field test for the accumulation of the atmospheric refraction error indicate that random error and systematic error unrelated to refraction competed with the systematic refraction error and severely complicate any analysis of the test results. If...
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...
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...
H.T. Haselton Jr., G.L. Hovis, B. S. Hemingway, R. A. Robie
1983, American Mineralogist (68) 398-413
Heat capacities (5-380 K) have been measured by adiabatic calorimetry for five highly disordered alkali feldspars (Ab99Or1, Ab85Or15, Ab55Or45, Ab25Or75 and Ab1Or99). The thermodynamic and mineralogical implications of the results are discussed. The new data are also combined with recent data for plagioclases in order to derive a revised expression...
Daniel Moos, Mark D. Zoback
1983, Journal of Geophysical Research Solid Earth (88) 2345-2358
A study of the effects of macroscopic fractures on P and S wave velocities has been conducted in four wells drilled in granitic rock to depths between 0.6 and 1.2 km. The effect of macroscopic fractures is to decrease both Vp and Vs and increase Vp/Vs. In wells with a relatively low density of macroscopic fractures, the in situ...
C. R. Bacon
1983, Journal of Volcanology and Geothermal Research (18) 57-115
New investigations of the geology of Crater Lake National Park necessitate a reinterpretation of the eruptive history of Mount Mazama and of the formation of Crater Lake caldera. Mount Mazama consisted of a glaciated complex of overlapping shields and stratovolcanoes, each of which was probably active for a comparatively short...
D. Zhou, T. Chang, J.C. Davis
1983, Journal of the International Association for Mathematical Geology (15) 581-606
It is mathematically possible to extract both R-mode and Q-mode factors simultaneously (RQ-mode factor analysis)by invoking the Eckhart-Young theorem. The resulting factors will be expressed in measures determined by the form of the scalings that have been applied to the original data matrix. Unless the measures for both solutions are...
M. Tatsumoto
1983, Geochimica et Cosmochimica Acta (47) 984
No abstract available....
R. A. Zielinski
1983, Journal of Geochemical Exploration (18) 285-306
Fine-grained tuffaceous sediments of the White River Formation (Oligocene) are evaluated as a possible source of uranium for the sedimentary uranium deposits of Wyoming. The evaluation is based upon a model in which volcanic glass is considered to be a major host of uranium and thorium and in which uranium...
M. B. Goldhaber, R. L. Reynolds, R. O. Rye
1983, Economic Geology (78) 1043-1063
The Lamprecht and Felder deposits are roll-type deposits hosted by the Miocene Oakville Sandstone. Four distinct stages of FeS 2 mineral formation are recognized: (1) a generation of isotopically light (delta 34 S < -20 per mil) preore pyrite, (2) a generation of isotopically light (delta 34 S < -20 per mil) marcasite that formed mostly...
J.C. Cain, J. Frayser, L. Muth, D. Schmitz
1983, Journal of Geophysical Research Solid Earth (88) 5903-5910
A combined spatial and secular variation model of the geomagnetic field, labeled M061581, is derived from a selection of Magsat data. Secular variation (SV) data computed from linear fits to midnight hourly values from 19 magnetic observatories were also included in the analysis but were seen to have little effect...
W.F. Giggenbach, R. Gonfiantini, B.L. Jangi, A.H. Truesdell
1983, Geothermics (12) 199-222
The isotopic compositions of the waters discharged from Parbati Valley geothermal areas indicate a higher altitude meteoric origin, with discharge temperatures reflecting variations in the depth of penetration of the waters to levels heated by the existence of a ‘normal’ geothermal gradient. On the basis of mixing models involving silica,...
J.A. Westphal, M.A. Carr, W.F. Miller, D. Dzurisin
1983, Review of Scientific Instruments (54) 415-418
An unusually rugged highly sensitive and inexpensive bubble tiltmeter has been designed, tested, and built in quantity. These tiltmeters are presently used on two volcanoes and an Alaskan glacier, where they continuously monitor surface tilts of geological interest. This paper discusses the mechanical, thermal, and electric details of the meter,...