Six interlocking regional stratigraphic cross sections of Lower Cretaceous strata (middle Albian-lower Cenomanian) of the Edwards and Stockton Plateaus of West Texas illustrate the vertical and lateral extent of lithostratigraphic units and distribution of facies and facies tracts.

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 Tom Green, Irion, and Reagan Counties and parts of Midland, Glasscock, Sterling, Coke, Runnels, Concho, Menard, Schleicher, Crockett, and Upton Counties, Texas.

 Geologic map that depicts the surface geology of Sutton County and parts of Terrell, Crockett, Val Verde, Edwards, Kimble, Menard, Schleicher, and Pecos Counties.

Electrical images in boreholes are becoming increasingly important in interpreting the rock record.

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.

The Upper Triassic Dockum Group of Texas and New Mexico is composed of 200 to 2,000 feet of complexly interrelated terrigenous clastic facies ranging from mudstone to conglomerate.

The Upper Devonian Woodford Formation is an organic-rich petroleum source rock that extends throughout West Texas and southeastern New Mexico and currently is generating oil or gas in the subsurface.

Unrecovered mobile oil is oil that is movable at reservoir conditions but is prevented from migrating to existing we1 l bores because of geologic complexities or heterogeneities.

Canyon sandstones form a prolific low-permeability gas play in the Val Verde Basin of southwest Texas. Exploration and development activity is at a high level, but little published information on Canyon geology is available.