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Thomas E. Smith

Publications and source records attributed to Thomas E. Smith.

6 recordsLinked to original sources
USGS2015

Geologic maps of the eastern Alaska Range, Alaska (1:63,360 scale)

This report provides a description of map units for a suite of 44 inch-to-mile (1:63,360-scale) geologic quadrangle maps of the eastern Alaska Range. This report also contains a geologic and tectonic summary and a comprehensive list of references pertaining to geologic mapping and specialized studies of the region. In addition to the geologic maps of the eastern Alaska Range, this package includes a list of map units and an explanation of map symbols and abbreviations. The geologic maps display detailed surficial and bedrock geology, structural and stratigraphic data, portrayal of the active Denali fault that bisects the core of the east–west-trending range, and portrayal of other young faults along the north and south flanks of the range.

Alaska↗
USGS1992

Map, tables, and summary of fossil and isotopic age data, Mount Hayes Quadrangle, eastern Alaska range, Alaska

This report describes, summarizes, and interprets all known bedrock fossil and isotopic age studies for the Mount Hayes quadrangle, eastern Alaska Range, Alaska. The accompanying map shows the location of all known bedrock fossil and isotopic sample localities in the quadrangle on a generalized geologic base map. These fossil and isotopic age data are obtained from new studies, unpublished data of the U.S. Geological Survey, contributed unpublished data, and published data. This report is one result of a five-year mineral resource assessment of the quadrangle that was done during the summers of 1978 through 1982, with additional topical studiesin 1985 and 1986. This report is one part of a folio on the geological, geochemical, geophysical, and mineral-resource assessment studies of the quadrangle prepared as part of the Alaskan Mineral Resource Assessment Program (AMRAP) of the U.S. Geological Survey.

Alaska↗
USGS1970

Results of geochemical sampling in the western Clearwater Mountains, Alaska

Two centers of gold mineralization in the Clearwater Mountains have been identified during a recent geochemical sampling program in the Healy A-1, B-1 quadrangles, Alaska. Both the Timberline Creek center and the Black Creek center are located near the same E-W trending fault system. Sites of structural weakness along the zone have apparently guided the emplacement of small diorite and quartz diorite stocks that acted as hosts for later gold-quartz-carbonate veins. Recurrent movement along the faults has fractured and locally sheared the intrusives, providing discontinuous dilatant areas for subsequent vein deposition. Most of the auriferous veins are locallized within the fractured intrusives, although gold values in the range 0.02 to 20 ppm are found in much of the limonitic shear zone material in both intrusive and country rock. The coincidence of gold centers with intrusive bodies appears to be principally a tectonic association. Fractured dilatant intrusives along a generally impermeable fault zone have functioned as pipe-like avenues of ascent for mineralizing fluids. A close association of gold and arsenic exists in both stream-sediment and bedrock geochemical samples. Mercury is concentrated along the major E-W trending shear system, but occurs between the gold centers, implying a crude hypogene zonation outward from the centers along the mineral belt. The Denali Copper Prospect, discovered in 1963 (Kaufman, 1964, p. 6) and currently being explored is similarly located at a structural intersection along a major shear system trending N. 75° E. Additional minor occurrences of copper are located to the west along the same fault system on the south side of Windy Creek.

Alaska↗