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James E. Case

Publications and source records attributed to James E. Case.

At least 19 recordsLinked to original sources
USGS1995

Geologic map of Port Moller, Stepovak Bay, and Simeonof Island quadrangles, Alaska Peninsula, Alaska

Geologic mapping of Port Moller, Stevopak Bay, and Simeonof Island 1° by 2° quadrangles on the Alaska Peninsula was conducted as part of the Alaska Mineral Resource Assessment Program (AMRAP). Geologic observations was obtained by using helicopter overflights, vertical aerial photography, and enhanced and extensively processed Landsat imagery (York and others, 1984; Wilson and York, 1985). Helicopter-supported field investigations were conducted from Sand Point in 1982 and 1986 and from both Sand Point and Port Moller in 1985 and 1985. In addition, field work was conducted from the U.S. Geological Survey Research Vessel Don J. Miller II in 1983 and 1984. The mapping of Burk (1965), Kennedy and Waldron (1955), and Moore (1974) provided an excellent basis for the AMRAP mapping. The present map duplicates both Moore’s map of the outer Shumagin Islands and Kennedy and Waldron’s map of the Pavlof Volcano area with minor additions. However, important changes have been made to Burk’s pioneering work.

Alaska↗
USGS1985

Preliminary description of a Miocene zone of structural complexity, Port Moller and Stepovak Bay quadrangles, Alaska: A section in The United States Geological Survey in Alaska: Accomplishments during 1983

A zone of structural disruption and complexity along the Pacific coast margin of the Alaska Peninsula (fig. 41) may be related to the Alaska Peninsula and the Chugach terrane boundary. The best exposure of this zone is located on the east shore of Humpback Bay (figs. 42, 43; also Burk, 1965, pl. 8, fig. 4); other exposures are located on the east side of Ivanof Bay, the north and south sides of Lefthand Bay, and in other coastal localities in the area. In some places, such as on the Kupreanof Peninsula, it is not recognized. This zone may extend discontinuously for 110-160 km along the coast; the width of the zone varies from 0.5 to 1 km. Our current data and tentative interpretations are described here, pending completion of additional field research, laboratory, and office studies.

Alaska↗
USGS1982

Metalliferous mineral resource potential of the Seward and Blying Sound quadrangles, southern Alaska

This mineral potential map is the final report in a series of publications that makes up a folio on the Seward and Blying Sound quadrangles of southern Alaska. It draws on data largely presented in previous publications of the folio. The studies were undertaken as part of the Alaska Mineral Resource Assessment Program (AMRAP), a program designed to provide information for Federal, State, local, and industry decisions concerning the future uses of Alaskan lands and resources.

Alaska↗
USGS1969

Aeromagnetic investigation of crustal structure for a strip across the western United States

This report represents part of a larger study undertaken to interpret the gross features of the earth's crust by aeromagnetic methods. The larger survey covers a 100-mile-wide strip along a great circle arc from Washington, D.C., to San Francisco, California. The area considered extends from about 200 miles east of the Rocky Mountains to 150 miles west of the coast of the Pacific Ocean. Inferences on gross structure and lithology are made from the magnetic patterns and trends shown on the map. At the continental margin, the magnetic data strongly suggest that the oceanic crust becomes much more deeply buried as the continent is approached. A large magnetic anomaly extending northwestward along the center of the Great Valley is probably caused by mafic intrusive rocks.

California, Colorado, Kansas, Nebraska, Nevada, Ut↗