The geology exposed at the surface in the southern Illinois Basin has been mapped in great detail by countless workers over the past century. With the exception of limited and scattered exposures in incised river valleys, the oldest rocks exposed outside of the Jessamine, Nashville, and Ozark Domes surrounding the Illinois Basin are Mississippian in age. Extensive deposits of Cambrian–Devonian sediments occur in the subsurface above crystalline basement in this region, however. All available data for the region were analyzed to produce a single, comprehensive set of interpretations. The data used in this study include 1:24,000-scale geologic quadrangle maps, oil and gas well data from 1,764 wells, more than 900 mi of proprietary reflection-seismic profiles, and public-domain potential-fields data (gravity and aeromagnetic surveys). The data were used to interpret the structure of eight stratigraphic horizons in the subsurface: the top and base of the New Albany Shale, the top and base of the Maquoketa Shale, the top of the Knox Supergroup, the top of the Eau Claire Formation, the top of the Reelfoot Arkose, and the top of Precambrian basement rocks.
Report of Investigations 10
Digital Object Identifier (DOI)
This research was completed by the Kentucky Geological Survey in Lexington, Ky. It was funded in part by a research consortium composed of 11 oil and gas exploration companies, as well as the Governor’s Office of Energy Policy and the Kentucky Energy and Environment Cabinet. The Rough Creek Graben Consortium included the fol-lowing companies: Chesapeake Energy, Forest Oil Corp., Greensburg Oil, Highway Resources, Marathon Oil Co., MegaWest (Kentucky Resources), MSD Energy, North Coast Energy, Sunshine Oil & Gas, Triana Energy, and Viking Energy LLC.
Hickman, John B., "Major Lower Paleozoic Horizons of the Southern Illinois Basin" (2019). Report of Investigations--KGS. 57.