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...
Calculation of amorphous silica solubilities at 25° to 300°C and apparent cation hydration numbers in aqueous salt solutions using the concept of effective density of water
Robert O. Fournier, Marshall L. Williams
1983, Geochimica et Cosmochimica Acta (47) 587-596
The solubility of amorphous silica in aqueous salt solutions at 25° to 300°C can be calculated using information on its solubility in pure water and a model in which the activity of water in the salt solution is defined to equal the effective density. pe, of “free” water in that solution....
Snow and ice in a changing hydrological world
M. F. Meier
1983, Hydrological Sciences Journal (28) 3-22
On the occasion of the 60th anniversary of the International Association of Hydrological Sciences, the 100th and 50th anniversaries of the First and Second International Polar Years, and the 25th anniversary of the International Geophysical Year, it seems appropriate to re-examine the world's water balance and the role of snow...
Characteristics of resuspended sediment from Georges Bank collected with a sediment trap
C.M. Parmenter, Michael H. Bothner, B. Butman
1983, Estuarine, Coastal and Shelf Science (17) 521-533
A sediment trap was deployed 3 m from the bottom at a water depth of 62 m on the southern flank of Georges Bank (41°02·2′N, 67°33·5′W) from 30 September 1978 to 10 March 1979 to qualitatively determine the size of sediments resuspended from the bottom by winter storms and to...
Variable tolerance to copper in two species from San Francisco Bay
Samuel N. Luoma, D.J. Cain, K. Ho, A. Hutchinson
1983, Marine Environmental Research (10) 209-222
In static toxicity experiments, tolerance to soluble Cu of the bivalve, Macoma balthica, and the copepod, Acartia clausi, varied substantially among populations sampled within San Francisco Bay. Intraspecific tolerance differed ten-fold or more for both species over relatively small distances, suggesting geographical isolation of populations is not a prerequisite for...
Nucleation and growth of strike slip faults in granite
P. Segall, D.P. Pollard
1983, Journal of Geophysical Research Solid Earth (88) 555-568
Fractures within granodiorite of the central Sierra Nevada, California, were studied to elucidate the mechanics of faulting in crystalline rocks, with emphasis on the nucleation of new fault surfaces and their subsequent propagation and growth. Within the study area the fractures form a single, subparallel array which strikes N50°–70°E and...
Submarine hydrothermal metamorphism of the Del Puerto ophiolite, California
Russell C. Evarts, Peter Schiffman
1983, American Journal of Science (283) 289-340
No abstract available....
Introduction: seismology and earthquake engineering in Central and South America.
A. F. Espinosa
1983, Earthquake Information Bulletin (USGS) (15) 4-6
Reports the state-of-the-art in seismology and earthquake engineering that is being advanced in Central and South America. Provides basic information on seismological station locations in Latin America and some of the programmes in strong-motion seismology, as well as some of the organizations involved in these activities.-from Author...
Can the earth be dated from decay of its magnetic field?.
G. 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,...
Reinterpretation of the exposed record of the last two cycles of Lake Bonneville, Western United States
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...
Correlation of Alaskan varve thickness with climatic parameters, and use in paleoclimatic reconstruction
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...
A quantitative comparison of Soil Development in four climatic regimes
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...
Taeniolite, an uncommon lithium-mica from Coyote Peak, Humboldt County, California.
Richard C. Erd, G.K. Czamanske, C.E. Meyer
1983, Mineralogical Record (14) 39-40
Taeniolite has been found in a late pegmatitic clot in a mafic alkalic diatreme at Coyote Peak; associated species are natrolite, pectolite, aegirine, barytolamprophyllite, rasvumite and sphalerite. The taeniolite is green-brown with sp. gr. (meas.) 2.85(1) and H. 31/2. Optically it is biaxial (-) with alpha 1.541(2), beta = gamma...
Distribution of mineral deposits in accreted terranes and cratonal rocks of western United States
J. P. Albers
1983, Canadian Journal of Earth Sciences (20) 1019-1029
The western margin of the conterminous United States, covering roughly 300 000 mi2 (777 000 km2), is an agglomeration of tectonostratigraphic terranes accreted to the North American craton mainly during Mesozoic time. The terranes represent a number of fundamental crustal types: oceanic crust, island-arc crust, mélange, various combinations of the preceding three, batholithic, miogeoclinal, and...
Tuffaceous sediments as source rocks for uranium: A case study of the White River Formation, Wyoming
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...
Dual extraction of R-mode and Q-mode factor solutions
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...
Eruptive history of Mount Mazama and Crater Lake Caldera, Cascade Range, U.S.A.
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...
An examination of the southern California field test for the systematic accumulation of the optical refraction error in geodetic leveling
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...
On the reported optical activity of amino acids in the Murchison meteorite
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...
Reassessment of the rates at which oil from natural sources enters the marine environment
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...
Thermal areas on Kilauea and Mauna Loa Volcanoes, Hawaii
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...
Structure and petrology of the La Perouse gabbro intrusion, Fairweather Range, southeastern Alaska
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...
Tectonic uplift of a middle Wisconsin marine platform near the Mendocino triple junction California
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....
In situ capture gamma-ray analysis of coal in an oversize borehole
J.L. Mikesell, D.W. Dotson, F. E. Senftle, R.S. Zych, J. Koger, L. Goldman
1983, Nuclear Instruments and Methods In Physics Research (215) 561-566
In situ capture gamma-ray analysis in a coal seam using a high resolution gamma-ray spectrometer in a close-fitting borehole has been reported previously. In order to check the accuracy of the method under adverse conditions, similar measurements were made by means of a small-diameter sonde in an oversize borehole in...
Ground water for oil-shale development, Piceance Basin, Colorado
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...
