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Munsell color value as related to organic carbon in Devonian shale of Appalachian basin

Comparison of Munsell color value with organic carbon content of 880 samples from 50 drill holes in the Appalachian basin shows that a power curve is the best fit for the data. A color value below 3 to 3.5 indicates the presence of organic carbon but is meaningless in determining the organic carbon content because a large increase in amount of organic carbon causes only a minor decrease in color v
Authors
John W. Hosterman, Sallie I. Whitlow

Seismic evidence for an extensive gas-bearing layer at shallow depth, offshore from Prudhoe Bay, Alaska

High-resolution seismic reflection data, recorded offshore from Prudhoe Bay, Alaska, were processed digitally to determine the reflectivity structure of the uppermost layers of the seafloor. A prominent reflector, found at 27 m below the mud line (water depths 7-9 m), has a negative reflection coefficient greater than 0.5. The large acoustic impedance contrast, coupled with a report of gas encount
Authors
G. Boucher, E. Reimnitz, E. Kempema

Economics and coal resource appraisal: strippable coal in the Illinois Basin ( USA)

Coal-resource appraisals generally describe the location and general characteristics of coal beds. Estimates are made of the average overburden depth (depth of the coal bed below the surface), bed thickness, and perhaps certain chemical properties of the coal [1]. Although such resource compilations represent an important initial step, neither they nor current estimates provide sufficient informat
Authors
E.D. Attanasi, E.K. Green

Two examples of seismic zonation in the San Francisco Bay region

The science of earthquakes in complex, requiring data and research in seismology, geology, soil mechanics, geophysics, hydrology, and engineering. Nevertheless, if earthquake hazards are to be reduced, earth science information must be translated from scientific and technical language into a form that can be effectively used by planners and decisionmakers. Out of the need to use earth science info
Authors
W. J. Kockelman, E. E. Brabb

Two oil types on North slope of Alaska: Implications for exploration

Forty oil samples from across the North Slope of Alaska have been analyzed by the U.S. Bureau of Mines and the U.S. Geological Survey. Results of these analyses suggest two separate genetic oil types. The first, the Simpson-Umiat oil type, occurs in reservoir rocks of Cretaceous and Quaternary age and includes oil from seeps in the Skull Cliff, Cape Simpson, Manning Point, and Ungoon Point areas,
Authors
L. B. Magoon, G. E. Claypool

Physical factors that could restrict mineral supply

Stages in the metal supply process are affected by each of the following physical (geologic) factors: (1) geographic distribution of concentrations of potential ore minerals, (2) depth of these concentrations, (3) mineralogy, (4) grain size of the minerals, and (5) grade and (6) tonnages of the concentrations. For mineral deposits of each type in each geologic and political environment, the lowest
Authors
John H. DeYoung, Donald A. Singer

Magnetic effects of maghemitization of oceanic crust

Both theoretical considerations and available experimental results indicate that magnetic effects of maghemitization are strongly dependent on the grain size of the originally unoxidized titanomagnetite. Maghemitization of single‐domain titanomagnetite results in a decrease in coercivity, an increase in susceptibility, and a large decrease in Q ratio. Maghemitization of multidomain titanomagnetite
Authors
M. Prevot, A. Lecaille, Edward A. Mankinen

Research in the Geysers-Clear Lake geothermal area, Northern California

The Geysers-Clear Lake area is one of two places in the world where major vapor-dominated hydrothermal reservoirs are commercially exploited for electric power production. Because energy can be extracted more efficiently from steam than from hot water, vapor-dominated systems are preferable for electric power generation, although most geothermal electric power facilities tap water-dominated system