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Page 5231, results 130751 - 130775

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Not all publications have extents, not all extents are completely accurate
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...
Landsat analysis of the Yangjiatan tungsten district, Hunan Province, People's Republic of China
W. D. Carter, T. H. Kiilsgaard
1983, Advances in Space Research (3) 113-123
The Yangjiatan tungsten district at latitude 27??28??? N. and longitude 111??54???E. is located about 140 km southwest of the city of Changsha and 35 km northeast of the town of Shaoyang, southeast Hunan Province, People's Republic of China. The deposits, consisting largely of scheelite in veins (Wang, 1975), are contained...
Mineral discrimination using a portable ratio-determining radiometer
G. Whitney, M. J. Abrams, Alexander F.H. Goetz
1983, Economic Geology (78) 688-698
The instrument has ten bands in the visible and near-infrared portion of the spectrum (0.5-2.4 mu m). Measurements and statistical analyses were performed on 66 samples, which were characterized by microscopic and X-ray diffraction analyses. On the ability to discriminate between 16 mineralogical groups, 91 percent classification accuracy was achieved....
A description of the external and internal quiet daily variation currents at North American locations for a quiet-Sun year.
W.H. Campbell
1983, Geophysical Journal of the Royal Astronomical Society (73) 51-64
An order 4, degree 12 spherical harmonic analysis of the smoothed quiet geomagnetic daily variations was used to separate the external and internal geomagnetic Sq field at North American locations for the quiet-Sun year, 1965. These fields were represented by a month-by-month display of equivalent current vortex systems with dominant,...
Lake phosphorus loading form septic systems by seasonally perched groundwater
R. J. Gilliom, C.R. Patmont
1983, Journal of the Water Pollution Control Federation (55) 1297-1305
The movement of effluent phosphorus (P) from old septic systems by seasonally perched groundwater was investigated. A previous study indicated a correlation between P loadings and the presence of old homes. Water samples were taken from shallow wells installed 10 to 50 m downgradient from seven septic systems 20 to...
Two examples of earthquake- hazard reduction in southern California.
W. J. Kockelman, C.C. Campbell
1983, Earthquake Information Bulletin (USGS) (15) 216-225
Because California is seismically active, planners and decisionmakers must try to anticipate earthquake hazards there and, where possible, to reduce the hazards. Geologic and seismologic information provides the basis for the necessary plans and actions. Two examples of how such information is used are presented. The first involves assessing the...
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...
Tectonics and metallogenic provinces
P. W. Guild
1983, Advances in Space Research (3) 9-16
Various theories have been advanced to explain the well-known uneven distribution of metals and ore-deposit types in space and time. Primordial differences in the mantle, preferential concentration of elements in the crust, the prevalence of ore-forming processes at certain times and (or) places, and combinations of one or several of...
Isotopic evidence from the eastern Canadian shield for geochemical discontinuity in the proterozoic mantle
L.D. Ashwal, J. L. Wooden
1983, Nature (306) 679-680
Most workers agree that Proterozoic anorthosite massifs represent the crystallization products of mantle-derived magmas1,2, although the composition of the parental melts is a major unsolved petrological problem 3. As mantle-derived rocks, the massifs can be used as geochemical probes of their late Precambrian upper mantle sources. We report here Nd...
Thermal decarboxylation of acetic acid: Implications for origin of natural gas
Y.K. Kharaka, W.W. Carothers, R.J. Rosenbauer
1983, Geochimica et Cosmochimica Acta (47) 397-402
Laboratory experiments on the thermal decarboxylation of solutions of acetic acid at 200°C and 300°C were carried out in hydrothermal equipment allowing for on-line sampling of both the gas and liquid phases for chemical and stable-carbon-isotope analyses. The solutions had ambient pH values between 2.5 and 7.1; pH values and...
Eastern Devonian shales: Organic geochemical studies, past and present
Irving A. Breger, Patrick G. Hatcher, L.A. Romankiw, F.P. Miknis
1983, Conference Paper, Preprints Symposia
The Eastern Devonian shales are represented by a sequence of sediments extending from New York state, south to the northern regions of Georgia and Alabama, and west into Ohio and to the Michigan and Ilinois Basins. Correlatives are known in Texas. The shale is regionally known by a number of...
U-Th-Pb systematics of zircon inclusions in rock-forming minerals: A study of armoring against isotopic loss using the Sherman Granite of Colorado-Wyoming, USA
J. N. Aleinikoff
1983, Contributions to Mineralogy and Petrology (83) 259-269
Zircon inclusions were separated from the five major rock-forming minerals of the Sherman Granite of southern Wyoming, in order to evaluate the degree of discordance as a possible function of host minerals. U-Th-Pb isotopic ratios were determined for two size fractions of zircon inclusions from each mineral, plus five size...
Isotopic studies of mariposite-bearing rocks from the south- central Mother Lode, California.
R. W. Kistler, F. C. W. Dodge, M.L. Silberman
1983, California Geology (36) 201-203
Gold-bearing vein formation in the Mother Lode belt of the study area apparently occurred during the Early Cretaceous between 127 and 108 m.y. B.P. The hydrothermal fluids that carried the gold precipitated quartz and mariposite at approx 320oC, similar to the T of precipitation of gold-bearing quartz veins in the...
Gas-film coefficients for streams
R. E. Rathbun, D. Y. Tai
1983, Journal of Environmental Engineering (109) 1111-1127
Equations for predicting the gas-film coefficient for the volatilization of organic solutes from streams are developed. The film coefficient is a function of windspeed and water temperature. The dependence of the coefficient on windspeed is determined from published information on the evaporation of water from a canal. The dependence of...
VARIATIONS IN MINERAL MATTER CONTENT OF A PEAT DEPOSIT IN MAINE RESTING ON GLACIO-MARINE SEDIMENTS.
Cornelia C. Cameron, Paul Schruben
1983, Conference Paper, Los Alamos National Laboratory (Report) LA
The Great Heath, Washington County, Maine, is an excellent example of a multidomed ombrotrophic peatland resting on a gently undulating surface of glacio-marine sediments and towering above modern streams. A comprehensive study sponsored by the Geological Survey of Maine in cooperation with the U. S. Geological Survey included preparation of...
Sorption of radium-226 from oil-production brine by sediments and soils
E. R. Landa, D.F. Reid
1983, Environmental Geology (5) 1-8
The sorption of226Ra from oil-production brine by soils and sediments was investigated. Sorption was rapid, and the percentage sorbed increased with brine dilution. Greatest removals of226Ra from sediments in the laboratory occurred with alkaline DTPA, HCl, and BaCl2, with lesser removals using CaCl2 and NaCl solutions. Digestion of sediments with...
GEOLOGIC FRAMEWORK FOR GEOTHERMAL ENERGY IN THE CASCADE RANGE.
W. A. Duffield
1983, Conference Paper, Transactions - Geothermal Resources Council
Quaternary volcanoes of the Cascade Range form a 1200-km-long belt from northern California to southwest British Columbia and lie above the subduction zone formed as the Juan de Fuca plate is consumed beneath North America. Volcanoes throughout this belt may have been active during Quaternary time, and many have erupted...
Rainfall intensity-duration-frequency formulas.
Chiu-Lan Chen
1983, Journal of Hydraulic Engineering (109) 1603-1621
A new general rainfall intensity-duration-frequency formula is presented, utilizing a method similar to, but more accurate than one previously developed. The previously developed formula was based on the average depth-duration ratio of about 40% and the mean depth-frequency ratio of 1.48. It is shown that this formula is only a...
Geological setting of oil shales in the Permian phosphoria formation and some of the geochemistry of these rocks
E. K. Maughan
1983, Conference Paper, Preprints Symposia
Recent studies of the Meade Peak and the Retort Phosphatic Shale Members of the Phosphoria Formation have investigated the organic carbon content and some aspects of hydrocarbon generation from these rocks. Phosphorite has been mined from the Retort and Meade Peak members in southeastern Idaho, northern Utah, western Wyoming and...