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 Red Cave Formation (Permian, Leonard Series) in the Texas Panhandle consists of cyclic, red-bed clastic and carbonate-evaporite members that reflect deposition in extensive coastal sabkhas. These environments were bounded on the north by a desert wadi plain and on the south by a carbonate inner shelf that bordered the northern Midland Basin. Evaporite members were deposited in carbonate evaporite coastal sabkhas, and clastic members were deposited in mud-rich coastal to continental sabkhas that passed inland to wadi-plain environments.

Texas lignite occurs in three Eocene (lower Tertiary) geologic units--the Wilcox Group, Jackson Group, and Yegua Formation--and in three ancient depositional systems--fluvial, deltaic, and strandplain/lagoonal. Near-surface resources in Texas at depths between 20 and 200 ft (6.1 and 61 m) in seams 3 ft (0.9 m) or thicker are 23,377 million short tons (21,208 million metric tons) and are dominantly fluvial in origin. More than 90 percent of the resources occur in the Wilcox and Jackson Groups north of the Colorado River.