Lignite deeper than 200 ft (61 m) constitutes about 60 percent of the total lignite resources in Texas. Projections indicate that meeting future demand will require mining this deep-basin lignite.

Mountain-bounded basins or bolsons are the most important aquifer systems throughout most of southwestern and western United States and northern Mexico.

Upper Miocene, Pliocene, and Pleistocene deposits in the subsurface of the central Coastal Plain of Texas were subdivided into six operational units comprising the surface-defined Fleming, Goliad, Willis, Lissie, and Beaumont Formations.

The Oakville Sandstone is a major aquifer and a major host of uranium deposits in the Texas Coastal Plain.

The Oligocene-Miocene fluvial uranium host aquifers of the South Texas uranium province were deposited principally as syndepositionally oxidized sands and muds.

The Oakville Formation consists of sediments deposited by several major fluvial systems that traversed the Texas Coastal Plain during the Miocene Epoch.

The Miocene Oakville Sandstone is a major aquifer and uranium host beneath the Texas Coastal Plain. In 1976, approximately 6,000 acre-ft of ground water were withdrawn from the Oakville for municipal use.

Eocene stratigraphic units in the East Texas Basin are composed of a thick sedimentary sequence (approximately 2,000 ft [600 m]) of fresh-water aquifers and aquitards covering an area of approximately 15,000 mi2 (51,000 km2).

The Ogallala aquifer, which underlies the Southern High Plains, consists of the saturated sediments of the Neogene Ogallala Formation. The aquifer is the main source of water for the High Plains of Texas and New Mexico and is being severely depleted by extensive pumpage for irrigation.