This full-color, oversize map, designed for hikers in the park, describes geologic units and features. The text documents the geologic history of the Big Bend Ranch State Park area. Support was provided by the Texas Parks and Wildlife Department and the U.S. Geological Survey.

Geologic map that depicts the surface geology of parts of Presidio, Brewster, and Terrell Counties, Texas. The 14-page booklet indicates geologic formations, abbreviations, and ages.

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 surface geology of parts of Hudspeth, Culberson, Jeff Davis, and Presidio Counties, Texas. The 12-page explanatory booklet indicates geologic formations, abbreviations, and ages.

Since production of fluorspar began in northern Coahuila, Mexico, in 1950-51, thousands of tons of high-grade ore have been mined from numerous deposits situated 5 to 75 miles south of the Rio Grande.

The West Chinati stock, well exposed in San Antonio Canyon and immediately westward on slopes of the southwestern part of the Chinati Mountains, Presidio County, Texas, is a large stocklike body of porphyritic hornblende granite cut by numerous dikes and irregular-shaped plutons of rhyolite, rhyo

This report describes preliminary results of an ongoing study of the volcanic stratigraphy, caldera activity, and known and potential mineralization of the Chinati Mountains area of Trans-Pecos Texas. Many ore deposits are spatially associated with calderas and other volcanic centers.

This compilation of potassium-argon (K-Ar) ages of igneous rocks of the Tertiary volcanic field of Trans-Pecos Texas includes all published ages known to us as well as many unpublished results.