Lowstand valley fill and shelf-edge deltaic deposits in the Tannehill sandstone (Wolfcampian Cisco Group) in the Eastern Shelf of the Permian Basin are major targets for oil and gas exploration.

Sixteen depositional sequences, commonly called cyclothems, each composed mostly of limestone(retrogradational/transgressive) and siliciclastic (progradational/regressive) subsequences, or systems tracts, record the paleogeography during Late Pennsylvanian (Virgilian Epoch) and Early Permian (Wol

Four clastic depositional sequences compose the lower part of the Triassic Dockum Formation in the Palo Duro Basin.

The Palo Duro Basin is a broad structural low in the southern Texas Panhandle that formed as a result of nearly continuous Pennsylvanian and Permian subsidence. True complexity of this basin is unknown because of the sparsity of structural information.

In the Palo Duro Basin, the Wolfcampian Series (lower Permian) overlies Pennsylvanian (primarily Virgilian) strata and underlies the Wichita Group (Leonardian).

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.

The interaction of geomorphic and ground-water processes has produced the Caprock Escarpmentthat bounds the eastern margin of the Southern High Plains in the Texas Panhandle.

Ground water that moves downward from aquifers in clastic rocks of the Triassic Dockum Group and Neogene Ogallala Formation dissolves bedded halite and anhydrite in the Upper Permian evaporite section along the perimeter of the Southern High Plains in the Texas Panhandle.

This cross section set comprises 14 dip (E-W) sections and 9 strike (N-S) stratigraphic cross sections (with text), correlating upper Pennsylvanian (Virgilian) and lower Permian (Wolfcampian) strata throughout the subsurface in all or parts of 28 counties of North-Central Texas.

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.