Geology topics
G. R. Johnson
Publications and source records attributed to G. R. Johnson.
Initial report of the Petrophysics Laboratory
Current national requirements for energy and mineral resources, and for protection of the quality of the environment, have focused attention on the need to develop new methods and interpretation techniques to be used in understanding geologic systems. Geophysical surveys play a significant role in acquiring this information, particularly by providing data in the third dimension--at depth beneath the surface.
Forest stand classification in western Washington using Landsat and computer-based resource data
No abstract available.
Spectral gradient of lunar radiobrightness: Heat flow or volume scattering?
Lunar heat flow cannot be derived unambiguously from the spectral gradient of the radiobrightness. Volume scattering of microwaves by rock clasts within the lunar regolith results in a spectral component in the 5- to 30-centimeter range of wavelengths that is a significant fraction of that resulting from lunar heat flow.
Microwave radiometric survey of the San Joaquin nuclear project site, Kern County, California
An airborne microwave survey was made in the region of the San Joaquin nuclear project site near Bakersfield, Calif. The purpose of the study was to determine if the variability of soil emissivity due to moisture content is a valid near-surface expression of buried fault systems. The results showed the existence of linear-emissivity anomalies paralleling, and to some extent, overlying the Greeley and Pond-Poso Creek faults. The anomalies seem to be direct expressions of silt-filled, northwesterly trending channels of the Pond-Poso Creek-Tulare Lake distributary system. The location, orientation, and linearity of the distributary channels suggest an association with buried faults, but no relationship has yet been determined.
Aeromagnetic and generalized geologic map of the west-central part of the Seward Peninsula, Alaska
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Geological Survey investigations in the U12b.01 tunnel, Nevada Test Site
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Geological Survey investigations in the U12b.01 tunnel, Nevada Test Site
The U12b.01 tunnel is part of the U12b (Rainier) tunnel system driven northwestward from the east slope of Rainier Mesa (figs. 1 and 2). Geologic and geophysical studies in this tunnel were conducted by the U.S. Geological Survey on behalf of the Albuquerque Operations Office of the Atomic Energy Commission. This report includes a brief description of the stratigraphy and structure, and data on petrology, mineralogy, and chemical and physical properties of the rocks that are exposed in the tunnel. The U12b.01 tunnel trends N. 10° W., and connects with the Ul2b tunnel at about 500 feet from the portal (fig. 2). The U12b,01 tunnel is about 250 feet long and contains an alcove 40 feet long and 20 feet wide, and a shot chamber 17 by 20 feet. The tunnel is irregular and ranges from 6 to 15 feet in width and averages 7 feet in height. Much of the tunnel has been supported using 6-foot steel sets and wood planks for lagging Vertical and minimum cover over the shot chamber at west end of the tunnel are approximately the same, about 295 feet.