Geologic map that depicts the surface geology of Shackelford, Stephens, Palo Pinto, Callahan, and Eastland Counties and parts of Jones, Taylor, Runnels, Coleman, Brown, Comanche, Erath, Parker, and Hood Counties, Texas.

Geologic map that depicts the surface geology of Mills County and parts of Runnels, Coleman, Brown, Comanche, Erath, Hamilton, Coryell, Lampasas, San Saba, McCulloch, Concho, and Menard Counties. The 21-page booklet indicates geologic formations, abbreviations, and ages.

Geologic map that depicts surface geology of Tarrant, Dallas, Kaufman, Ellis, Johnson, Somervell, and Rockwall Counties and parts of Parker, Hood, Erath, Bosque, Hill, Navarro, Henderson, Van Zandt, and Hunt Counties, Texas.

The Lower Cretaceous Hosston and Hensel Sandstones are important sources of ground water in North-Central Texas.

Coal is found in six areas in Texas, including the large North-Central Texas field, a distinctive cannel coalfield in Webb County, and Late Cretaceous-age coals near Eagle Pass.

Based on need for convenient, small-scale cartographic units, the basal Cretaceous rocks in Texas from Red River to Burnet County and on the Callahan Divide are herein divided into three distinctive lithologic sequences.

Lower Cretaceous sands have long been important aquifers in Central, North-Central, and North Texas. In recent years these sands also have been sources of high-silica industrial or specialty-purpose sand.