Publications

A refined northeast Pacific plate-motion model provides a framework for analysis of the Tertiary volcanic and tectonic history of western Oregon and Washington. We examine three possible models for the origin of the allochthonous Paleocene and Eocene oceanic basalt basement of the Coast Range: (1) accretion to the continent of hot spot generated linear seamount chains; (2) accretion of thick ocean

Shimada Seamount is an isolated volcanic feature located between the Clipperton and Clarion Fracture Zones ∼1,150 km west of the East Pacific Rise and ∼600 km west of the inactive spreading center represented by the Mathematician Seamounts. It rises ∼3,900 m above the surrounding sea floor to within 50 m of present-day sea level. The area of Shimada Seamount should be volcanically dormant, because

No abstract available.

Under the provisions of the Wilderness Act (Public Law 88-577, September 3, 1964) and subsequent related legislation, the U.S. Geological Survey (USGS) and the U.S. Bureau of Mines (USBM) have been conducting mineral surveys of wilderness and primitive areas, and of other national forest lands being considered for wilderness designation. The Wilderness Act directs that the results of these surveys

The fiscal year 1983 Yearbook summarizes the activities of the U.S. Geological Survey in response to its scientific and regulatory missions.

The Weaver Bally Roadless Area includes approximately 22 sq mi in the Shasta-Trinity National Forest, Trinity County, California. A mineral survey indicates that an area of less than 1 sq mi in the northern part of the Weaver Bally Roadless Area has a substantiated mineral-resource potential for gold and silver; a much larger area has a probable mineral-resource potential for the same elements. Th

A mineral survey of the Yolla Bolly-Middle Eel Wilderness, California identified a mine with inferred resources of manganese and an occurrence with inferred resources of nickel. The adjacent Big Butte-Shinbone Roadless Area to the west has an area of probable potential for the occurrence of chromium-nickel-cobalt resources and mines with demonstrated and inferred resources of manganese and chrome-

No abstract available.

No abstract available.

A summary of recent significant scientific and economic results accompanied by a list of geologic, hydrologic, and cartographic investigations in progress.

No abstract available.

In order to refine correlations of surface-wave magnitude, fault rupture length at the ground surface, and fault displacement at the surface by including the uncertainties in these variables, the existing data were critically reviewed and a new data base was compiled. Earthquake magnitudes were redetermined as necessary to make them as consistent as possible with the Gutenberg methods and results,