This folded transparent map is at the same scale as its corresponding Geologic Atlas of Texas (GAT) sheet and can be superimposed on it to compare gravity information with surface geology.
Sandstone reservoirs deposited in microtidal barrier systems contain large oil and gas reserves in several Gulf Coast Basin plays. Three representative Frio Sandstone reservoirs in West Ranch field show that barrier-island sand bodies are complex mosaics of barrier-core, inlet-fill, flood-tidal-delta, washover-fan, barrier-flat, and shoreface facies. The proportions of these facies differ within progradational, aggradational, and transgressive barrier sand bodies.
Bedded salt of the Permian San Andres Formation, Palo Duro Basin, Texas, is under consideration for the isolation of high-level nuclear waste. To represent the variety of salt types present, 150 large (250 to 500 g), intact samples of bedded halite from the San Andres Formation and other saltbearing units were selected and then analyzed by a standardized procedure. The halite fraction of the sample was dissolved in anhydrous methanol by continuous reflux Soxhlet extraction, and the water content was measured by Karl Fischer titration.
Silver deposits occur in Precambrian, Permian, and Cretaceous red-bed sequences near Van Horn, Texas. These deposits are geochemically similar and contain economically important quantities of silver, copper, and lead, as well as anomalously high amounts of arsenic, zinc, cadmium, and molybdenum. Gold is not enriched. Primary minerals include chalcopyrite, tennantite-tetrahedrite, bornite, galena, sphalerite, acanthite, pyrite, marcasite, barite, and calcite. The deposits are dominantly steeply dipping veins. Strata-bound occurrences are near veins or closely spaced fractures.