Pervasively dolomitized, anhydritic carbonates of the upper San Andres Formation in the Emma field of West Texas constitute an upward-shallowing sequence of lithofacies representing four major depositional environments.

Natural gas in the United States consists of proved reserves in known reservoirs, of inferred reserves and undeveloped resources within these reservoirs, and of undiscovered resources.

The Palo Duro Basin of the Texas Panhandle and eastern New Mexico contains bedded Permian salts of sufficient thickness and depth for the basin to be considered as a potential site for long-term storage and isolation of high-level nuclear waste.

Sandstone in the Travis Peak (Hosston) Formation has been extensively modified by burial diagenesis. Permeability in much of the formation has been reduced to less than 0.1 md as a result of compaction, extensive precipitation of authigenic minerals, and minor pressure solution.

Deep brine aquifers of the Palo Duro Basin, Texas Panhandle, ranging in depth from about 1,000 to 3,000 m below land surface, are underpressured compared with the shallow Ogallala aquifer.

Changes in the position and stability of shorelines in the San Antonio Bay system (San Antonio, Espiritu Santo, and Mesquite Bays), Texas Gulf Coast, were documented using historical monitoring techniques.

Porous and permeable strata of the Deep-Basin Brine aquifer underlie bedded evaporites that are being considered as repositories for high-level nuclear waste isolation in the Palo Duro Basin, Texas Panhandle. Formation-water samples collected from four U.S.

Ground water that moves downward from aquifers in clastic rocks of the Triassic Dockum Group and Neogene Ogallala Formation dissolves bedded halite and anhydrite in the Upper Permian evaporite section along the perimeter of the Southern High Plains in the Texas Panhandle.

Lineament analysis was used to study the relationship between subsurface structure and surficial features in East Texas, southeastern Oklahoma, southwestern Arkansas, and northwestern Louisiana-areas of low topographic relief, moderate vegetation cover, and diverse land use.