Geologic map that depicts the  surface geology of parts of Jeff Davis, Reeves, Pecos, Terrell, Brewster, and Presidio Counties, Texas. The 9-page booklet indicates geologic formations, abbreviations, and ages.

Geologic map that depicts the surface geology of Loving, Crane, and Ward Counties and parts of Ector, Midland, Upton, Pecos, Reeves, Crockett, and Winkler Counties, Texas. The 5-page booklet indicates geologic formations, abbreviations, and ages.

Geologic map that depicts the surface geology of El Paso County and parts of Hudspeth. Jeff Davis, and Culberson Counties, Texas. The 12-page booklet indicates geologic formations, abbreviations, and ages. Published in honor of E.

Studies of physiographic relations and of fossil molluscan faunas made in the Pecos River valley region (Val Verde County to the Texas�New Mexico border) reveal extensive, well-pedimented surfaces southwest of the river extending from the Davis Mountains to near the present channel.

Study of Permian, Cretaceous, and Cenozoic rocks in the 30 Kent quad- rangle is important to an understanding of the geology of Trans-Pecos Texas. Most of the Cretaceoua rock units of central Texas lose their lithostratigraphic identity when traced into west Texas.

At the northern end of the Coahuila platform, the thinned Comanchean sequence consists of the newly named Sixshooter group of carbonate formations underlain by the newly named Yearwood formation.

The Barrilla Mountains, in the northeastern part of the Davis Mountains of Trans-Pecos Texas, are composed of Tertiary volcanic materials. Five tuffs and five lava flows, 1500 feet thick occurring throughout the mountains, persist in thickness and lithologic characteristics.

The occurrence of sulphur in the vicinity of Rustler Springs in northeastern Culberson County, Texas, has been known since 1854 when, according to Phillips (1902, pp. 13, 71), the mineral was recognized by William P. Blake, a geologist attached to a U.S.

These circulars issued from the Bureau of Economic Geology contain the record of cores and cuttings from well received and described in the Bureau.