Thirty-one low-permeability gas-bearing sandstones in 15 sedimentary basins were surveyed to delineate the major depositional systems and associated facies of each stratigraphic unit. The depositional system of each unit provides a basis of comparison between formations of different ages in different structural and sedimentary settings.

Oversize color geologic map that depicts the surface geology of Dallam County and parts of Sherman, Moore, and Hartley Counties, Texas. The 6-page booklet indicates geologic formations, abbreviations, and ages.

Sand dunes at Monahans Sandhills State Park display a variety of dune forms that develop under a unique trimodal wind regime. Large expanses of unvegetated sand form akle dunes having reversing slip faces. Smaller dune forms in the park include wind-shadow, coppice, transverse, barchan, and parabolic dunes.

Correct interpretation of the effect of basin infilling on salt mobilization is critical to understanding salt dome growth and stability. The size of salt structures in the East Texas Basin is determined by the original thickness of the underlying Louann Salt (Middle Jurassic).

Post-Aptian strata (younger than 112 ma) in the East Texas Basin were strongly influenced by halokinesis and recorded the evolution associated sate structures.