Search USGSSearch

Geology topics

S. J. Sutley

Publications and source records attributed to S. J. Sutley.

At least 55 records · Page 3Linked to original sources

Maps showing distribution of iron, cobalt, barium, strontium, arsenic, antimony, and bismuth in samples of minus-60-mesh (0.25-MM) stream sediment and (or) nonmagnetic heavy-mineral concentrate, Walker Lake 1 degree by 2 degrees Quadrangle, California and Nevada

This report is part of a folio of maps of the Walker Lake 1 o x 2 o quadrangle, California and Nevada, prepared under the Conterminous United States Mineral Assessment Program. The folio includes geological, geochemical, and geophysical maps, as well as mineral resources assessment maps, which identify selected known or possible mineral-deposit environments in the quadrangle. The geochemical maps show the distributions of selected individual elements (Chaffee and others, 1988 a, b, c) and the distributions of selected groups of elements (Chaffee, 1988a, b, c). Discussions accompanying the individual element maps are restricted to mineral residences of the individual elements as well as to what types of mineral deposits and environments may be represented by anomalies of a particular element. Discussions accompanying the multielemental maps describe the types of mineral deposits that may be related to each element group and indicate the most favorable localities for these deposits.

California, Nevada

Summary geochemical maps for samples of rock, stream sediment, and nonmagnetic heavy-mineral concentrate, Cypress Roadless Area, Kern County, California

The Cypress Roadless Area comprises approximately 3 square miles (1,949 acres) of Sequoia National Forest, Kern County, California. The area is at the southern end of the Sierra Nevada, approximately 30 miles east-northeast of Bakersfield, and 2.5 miles and 3.5 miles south-southeast of the communities of Bodfish and Lake Isabella, respectively (index map). Geochemical sampling was conducted during 1980 and 1981. This report summarizes the results of that investigation and provides details of the geochemical evaluation used in the final mineral resource assessment of the study area (Kennedy and others, 1983). Map A shows the locations of all sites sampled for this report and the distributions of anomalous concentrations of 4 elements in 33 samples of rock, 5 elements in 34 samples of minus-60-mesh stream sediment, and 11 elements in 33 samples of nonmagnetic heavy-mineral concentrate derived from stream sediment. Map B shows outlines of those drainage basins containing samples of stream sediment and concentrate with anomalous concentrations and also shows weighted values for each outlined basin based on the number of elements with anomalous concentrations in each stream-sediment and concentrate sample and on the degree to which these concentrations are anomalous in each sample.

California

Near-infrared spectra of West Shasta gossans compared with true and false gossans from Australia and Saudi Arabia

The near-infrared spectra of a suite of outcrop samples of massive sulfide gossans and false gossans representing three different weathering environments were measured and studied with X-ray, scanning electron microscope, and energy dispersive X-ray. Gossans that formed in a humid tropical environment are represented by samples from the Mt. Isa area, Queensland, Australia, and gossans that formed in an arid environment are represented by samples from several locations in Saudi Arabia. The gossans of the West Shasta massive sulfide district in California represent a weathering environment intermediate between these two extremes.On the basis of these spectral measurements, true gossans after massive sulfide deposits have spectra in the 800 to 2,500 nanometer (nm) region that are distinctly different from the spectra of false gossans. In the humid tropical environment, highly leached, newly formed kaolin minerals in the gossan cause spectral differences at about 1,400 to 2,200 nm. In the arid environment, true gossans preserve talc and minor mica from the massive sulfide deposit; these minerals are not observed in false gossans. These minerals result in spectral differences in the 2,200- to 2,300-nm region. In addition, true gossans generally have goethite spectral bands at about 900 nm as opposed to hematite spectral bands at about 850 nm for the false gossans.False gossans are not known in the West Shasta district; however, the gossan at the largest deposit, Iron Mountain, is a true gossan that has the distinctive spectral features of goethite at about 900 nm and diaspore in the 1,400- to 2,500-nm region. The other gossans also have the spectral features of goethite, but they contain a less leached mixture of kaolinite plus illite and have distinctive spectral features in the 1,400- to 2,500-nm region. These spectral differences define two groups of West Shasta gossans--inner gossans in large deposits and outer gossans at the margins of large deposits and in lesser massive sulfide deposits.

Economic Geology

Map showing the distribution of selected mineral assemblages in nonmagnetic heavy-mineral concentrates from stream sediments from the Vasquez Peak Wilderness Study Area, and the Williams Fork and St. Louis Peak Roadless Areas, Clear Creek, Grand, and Summit counties, Colorado

The U.S. Geological Survey and the U.S. Bureau of Mines conducted field studies from 1979 through 1983 to assess the mineral resource potential of the Vasquez Peak Wilderness Study Area (acreage: 16,000), the Williams Fork Roadless Area (acreage: 74,820), and the St. Louis Peak Roadless Area (acreage: 12,800). Included were geological, geochemical, and geophysical studies by the U.S. Geological Survey and investigation of known prospects and mines by the U.S. Bureau of Mines.

Colorado

Summary geochemical maps, Hoover Wilderness and adjacent study area, Mono and Tuolumne counties, California

The Hoover Wilderness and the adjacent Hoover Extension (East), Hoover Extension (West), and Cherry Creek A Roadless Areas (the adjacent study area) encompass approximately 153,900 acres (241 mi 2 ; 623 km 2 ) in the Inyo, Stanislaus, and Toiyabe Naitonal Forests, Mono and Tuolumne Counties, Calif. These two areas lie along and mostly east of the crest of the Sierra Nevada, along the north and east sides of Yosemite National Park. Elevations vary from a high of 12,446 ft (3,793 m) on the crest of the Sierra Nevada to a low of about 6,500 ft (1,981 m) near the Bridgeport Ranger Station. Access to the Hoover Wilderness and adjacent study area is by U.S. Highway 395, California State Highways 108 (Sonora Pass) and 120 (Tioga Pass), and by other paved and graded roads that lead off of these U.S. and State highways.

California