Baranoski, Mark T.1
(1) Ohio Division of Geological Survey, Columbus, OH
ABSTRACT: Revised Subsurface Cambrian Sub-Knox Lithostratigraphy for Ohio Suggests the Proto Illinois-Michigan Basin Was Separated from the Rome Trough and Proto Appalachian Basin by Precambrian Paleotopography
The Ohio Division of Geological Survey is using deep continuous core calibrated to wire-line log suites, core analyses, and seismic reflection data to revise Ohio’s Cambrian sub-Knox lithostratigraphy. Preliminary mapping of revised units suggest that the Mount Simon Sandstone was deposited on a complex Precambrian paleotopographic unconformity surface; was limited to western Ohio and adjacent areas of Michigan, Indiana, and Kentucky; and is not a regional Cambrian “blanket sandstone” as traditionally mapped. The Mount Simon’s eastern limit defined a subcrop edge at an exposed Precambrian unconformity surface, which extended from the Canadian shield above present day Lake Erie southward to the northwestern Rome Trough boundary fault system. This regional paleotopographic high area controlled Cambrian depositional facies and separated the proto Illinois-Michigan Basin from the Rome Trough and proto Appalachian Basin. Seismic reflection data suggests Mount Simon fluvial depositional systems incised the Precambrian surface and supplied sediments to the Rome Trough and/or proto Illinois-Michigan Basin. Following deposition of the Mount Simon, the Eau Claire Formation of western Ohio merged across the Ohio region with the Conasauga Group of eastern Ohio forming a regional platform dominated by cyclic mixed clastic-carbonate sediments throughout central Ohio. Near the end of this mixed-clastic-carbonate sedimentation, all Precambrian paleotopography was completely buried. This new work has implications for basin analyses, crustal and tectonic studies, reservoir studies for industrial waste disposal, gas storage, CO2 sequestration, and hydrocarbon exploration.
AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.