This book provides a regional stratigraphic and depositional framework of the Virgilian and Wolfcampian Series of North-Central Texas. The authors have identified 16 major and several minor depositional sequences, commonly called cyclothems, deposited during Late Pennsylvanian and Early Permian regressive-transgressive episodes. These cyclothems were mapped from outcrop across the Eastern Shelf and into the Midland Basin. Seventeen maps and 23 cross-sections were constructed to show regional net-sandstone distribution within siliciclastic systems, to document sequential depositional history and paleogeography, to analyze depositional response to paleobathymetry and tectonics, and to offer a regional sequence-stratigraphic framework for evaluating controls on relative sea level. Regional perspective provided by the map series will stimulate new ideas about inadequately tested sandstone trends and unrealized stratigraphic-trap potential in this large, mature petroleum province.