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.

A mineral resource survey of Texas, started by the Works Progress Administration, is still being conducted by the Works Projects Administration, with the Bureau of Economic Geology of The University of Texas acting as the sponsor.