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At least 1,027 records · Page 57Linked to original sources
USGS1980

Geophysical logs and coal sections for four holes drilled in the Emery East quadrangle, Emery County, Utah

Four holes, for a total of 2,330 feet, were drilled in the Emery coal field, Utah, in April 1980 by the U.S. Geological Survey (fig. 1). Two of the holes were partially cored. The purpose of the drilling was to obtain information on the thickness, quality, and extent of the coal in the Cretaceous Ferron Sandstone Member of the Mancos Shale, and on the lithology of the surrounding rocks. Core samples were obtained to be used for coal quality and trace element analyses. The project is in support of the U.S. Geological Survey's continuing program to evaluate and classify Federal coal resources and lands in the public domain.

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USGS1981

Geophysical reconnaissance of Lemmon Valley, Washoe County, Nevada

Rapid growth in the Lemmon Valley area, Nevada, during recent years has put increasing importance on knowledge of stored ground water for the valley. Data that would fill voids left by previous studies are depth to bedrock and depth to good-quality water beneath the two playas in the valley. Depths to bedrock calculated from a gravity survey in Lemmon Valley indicate that the western part of Lemmon Valley is considerably deeper than the eastern part. Maximum depth in the western part is about 2 ,600 feet below land surface. This depression approximately underlies the Silver Lake playa. A smaller, shallower depression with a maximum depth of about 1,500 feet below land surface exists about 2.5 miles north of the playa. The eastern area is considerably shallower. The maximum calculated depth to bedrock is about 1,000 feet below land surface, but the depth throughout most the eastern area is only about 400 feet below land surface. An electrical resistivity survey in Lemmon Valley consisting of 10 Schlumberger soundings was conducted around the playas. The maximum depth of poor-quality water (characterized by a resistivity less than 20 ohm-meters) differed considerably from place to place. Maximum depths of poor-quality water beneath the playa east of Stead varied from about 120 feet to almost 570 feet below land surface. At the Silver Lake playa, the maximum depths varied from about 40 feet in the west to 490 feet in the east. (USGS)

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