Combining process and geomorphic description (supplied by studies of modern depositional systems) with the three-dimensional description of sedimentary units and their internal structures (accomplished in the stratigraphic record) produces an integrated facies model that can be applied to the interpretation of similar facies in other systems.

Annual report for the Bureau of Economic Geology 1976

Lignite deposits in Texas occur in three Eocene stratigraphic units: the Wilcox Group (lower Eocene), the Yegua Formation (upper Eocene), and the Jackson Group (upper Eocene). They are part of an extremely thick Gulf Coast Tertiary clastic sequence composed of an alternation of fluvial-deltaic and marine units. At the outcrop, the marine units are volumetrically insignificant. All units dip coastward at 1/4 deg to 2 deg (about 20 to 180 ft/mile).

The Texas Coastal Zone is marked by diversity in geography, resources, climate, and industry. It is richly andowed with extensive petroleum reserves, sulfur and salt, deep-water ports, intracoastal waterways, mild climate, good water supplies, abundant wildlife, commercial fishing resources, unusual recreational potential, and large tracts of uncrowded land in close proximity to major population centers.

The increasing demand for uranium combined with the improving economics of uranium production have resulted in a significant upsurge in exploration and mining efforts in the South Texas Coastal Plain uranium province. Texas ranks third in U.S. uranium production. Today, potentially commercial deposits have been delineated along an arcuate belt that stretches more than 250 miles from the Rio Grande into the middle Coastal Plain.