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G. R. Mansfield

Publications and source records attributed to G. R. Mansfield.

10 recordsLinked to original sources

Welded rhyolitic tuffs in southeastern Idaho

Rocks of rhyolitic type in eastern Idaho and adjacent parts of Wyoming were observed by the Teton Division of the Hayden Surveys under Orestes St. John (Report of the geological field work of the Teton Division, U.S. Geol. and Geog. Surv. Terr., 11th Ann. Rep., pp. 498–504, 1879), who described them as trachytes. He noted their relations to different types of underlying sedimentary rocks and their tendency to conform with the preexisting topography, but considered them all as flows. ©1935. American Geophysical Union. All Rights Reserved.

Idaho

Revision of the Beckwith and Bear River formations of southeastern Idaho

In the detailed geologic mapping of the Wayan and Montpelier quadrangles, in south-eastern Idaho and adjacent territory, it has been found necessary to apply new names to strata hitherto referred to the Beckwith and Bear River formations or to portions of the Laramie as mapped by the Hayden Survey. The two quadrangles are contiguous, and the Montpelier quadrangle lies south of the Wayan. They occupy the corner of the State and include a very narrow strip in northeastern Utah and a somewhat broader strip in western Wyoming.

Idaho