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A transect of metamorphic rocks along the Copper River, Cordova and Valdez Quadrangles, Alaska: A section in The United States Geological Survey in Alaska: Accomplishments during 1982 A transect of metamorphic rocks along the Copper River, Cordova and Valdez Quadrangles, Alaska: A section in The United States Geological Survey in Alaska: Accomplishments during 1982

The lower Tertiary Orca Group is juxtaposed against the Upper Cretaceous Valdez Group along the Contact fault system (Winkler and Plafker, 1974, 198; Plafker and others, 1977)(fig. 33). In both groups, turbidites are the dominant rock type, with lesser mafic volcanic rocks (table 10). The Valdez Group, on the north, has traditionally been considered to be of higher metamorphic grade than...
Authors
Marti L. Miller, Julie A. Dumoulin, S.W. Nelson

Preliminary results of potassium-argon age determinations from the Ugashik quadrangle, Alaska Peninsula: A section in The United States Geological Survey in Alaska: Accomplishments during 1980 Preliminary results of potassium-argon age determinations from the Ugashik quadrangle, Alaska Peninsula: A section in The United States Geological Survey in Alaska: Accomplishments during 1980

Early and preliminary results of potassiumargon dating work on samples from 12 sites in the Ugashik quadrangle indicate a continuation of the geologic trends seen in the Chignik and Sutwik Island quadrangles to the south (Wilson, 1980). Tertiary volcanic and hypabyssal rocks apparently fall into two age groups: early Tertiary-late Eocene to earliest Miocene and late Tertiary and...
Authors
Frederic H. Wilson, Nora B. Shew

Land subsidence due to the application of water Land subsidence due to the application of water

Loose, dry, low-density deposits that compact when they are wetted mantle extensive areas in North America, Europe, and Asia. This process, here referred to as hydrocompaction, has produced widespread subsidence of the land surface. Hydrocompaction may occur under natural overburden load or may occur only with the addition of a surcharge load. Deposits that subside because of...
Authors
Ben Elder Lofgren

Ground-water research in the U.S.A. Ground-water research in the U.S.A.

Ground-water reservoirs and the overlying unsaturated zone-collectively, the "subsurface"-have an enormous capacity to supply water to wells and useful plants, to store water to meet future needs for the same purposes, and, under suitable precautions, to accept wastes. This capacity can be exploited on a maximum scale, however, only on the basis of information one or more orders of...
Authors
C. L. McGuinness
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