Publications
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Uranium contents of glassy and devitrified andesites and dacites, Mount Mazama, Oregon
By direct comparison of devitrified and granophyrically crystallized specimens with nonhydrated glassy materials from the same units, Rosholt and coworkers (Rosholt and Noble, 1969; Rosholt et al., 1971) showed that specimens of primarily crystallized but otherwise unaltered peralkaline and subalkaline rhyolite from the western United States had lost from 30 to 80 percent of the uranium that they
Authors
D. C. Noble, W.I. Rose, Robert A. Zielinski
Tectonic relations of carbon dioxide discharges and earthquakes
CO2‐rich springs occur worldwide along major zones of seismicity. They are mostly in young orogenic belts, but some are in areas of rifting continental platforms. Analyses of 13C content indicate that much of the CO2 is derived from the mantle and that other important sources are the metamorphism of marine carbonate‐bearing sedimentary rocks and the degradation of organic material. The presence of
Authors
W. P. Irwin, Ivan Barnes
Uranium in secondary silica: A possible exploration guide
Study of uraniferous silica precipitates in the Shirley Basin, Wyoming, identified areas where ancient uraniferous ground water once ponded. Chalcedony collected from and directly beneath thick accumulations of rhyolite ash contain as much as 250 ppm uranium in a pre-ash topographic low and lesser concentrations (10 to 160 ppm) elsewhere. Differences in the U concentration of chalcedony collected
Authors
Robert A. Zielinski
Analysis of petroleum discovery data: A forecast of the date of peak production
No abstract available.
Authors
D. H. Root, Emil D. Attanasi
World petroleum resource estimates and production forecasts: Implications for government policy
Resource estimates alone will not give advance warning of encroaching production difficulties. An analysis of the general stages in the evolution of petroleum production and discovery and of industry statistics provides an estimate of when the stage characterised by increasing production in the market economy countries outside the United States and Canada will end. The analysis indicates that the
Authors
David H. Root, Emil D. Attanasi
Organic composition of some Upper Cretaceous shale, Powder River Basin, Wyoming
The lower Upper Cretaceous strata in northeastern Wyoming, which have yielded major quantities of oil and gas, were sampled at boreholes in Converse, Johnson, and Weston Counties. Cores of noncalcareous shale of largely nearshore-marine origin were obtained from the Frontier Formation and the overlying Cody Shale at depths of 3,780.6 to 3,879.9 m in Converse County, near the axis of the Powder Riv
Authors
E. Allen Merewether, G. E. Claypool
Preliminary geologic map of the Loma-Prieta Quadrangle, Santa Cruz and Santa Clara counties, California
No abstract available.
Authors
T.W. Dibblee, Earl E. Brabb
Preliminary geologic map of the La Honda and San Gregorio quadrangles, San Mateo County, California
No abstract available.
Authors
Earl E. Brabb
Porosity evolution of upper Miocene reefs, Almeria Province, southern Spain
Sea cliffs 40 km east of Almeria, southeastern Spain, expose upper Miocene reefs and patch reefs of the Plomo formation. These reefs are formed of scleractinian corals, calcareous algae, and mollusks. The reef cores are as much as 65 m thick and several hundred meters wide. Fore-reef talus beds extend 1,300 m across and are 40 m thick. The reefs and reef breccias are composed of calcitic dolomite.
Authors
A. K. Armstrong, P. D. Snavely, W. O. Addicott
Metamorphic infrastructure in the northern Ruby Mountains, Nevada
The metamorphic complex of the northern Ruby Mountains in northeastern Nevada exposes Paleozoic strata that are metamorphosed to sillimanite grade, migmatized, and recumbently folded. Nappes are variously overturned to the east, north, south, and west. The deeper part of this metamorphic infrastructure is a migmatitic zone pervaded by pegmatitic two-mica granite. A structurally higher transition z
Authors
Keith A. Howard