Includes scattered lacustrine, playa, and alluvial deposits of the Tahoka, Double Tanks, Tule, Blanco, Blackwater Draw, and Gatuna Formations, the latter of which may be Pliocene at base; outcrops, however, are basically of Quaternary deposits.
Alluvial and eolian deposits, and petrocalcic soils of the southern High Plains. Locally includes Qoa.
Blackwater Draw Formation
Upper Chinle Group, Garita Creek through Redonda Formations, undivided
In southwest includes the basalt-bearing Broken Jug Formation.
Cretaceous rocks, undivided
Includes associated alluvial and eolian deposits of major lake basins.