ABSTRACT

Identification of zones of recurrent basement faulting during basin infilling provides a framework for understanding sediment distribution patterns and lithologic variations in oil and gas reservoirs, coal seams, and salt beds in the Appalachian Basin. Two prominent fault zones, that have a history of recurrent Paleozoic displacement, are embedded in Precambrian Grenville basement in eastern Ohio. The faults have comparable Paleozoic reactivation histories, however they are likely of Precambrian antecedents with differing structural origins.

A narrow zone of basement faults, at least 160 miles (250 km) in length, that exhibits recurrent Paleozoic displacement extends N-S across northern West Virginia and N20°W across Ohio, nearly to Lake Erie. This zone includes the Burning Springs Anticline to the south and associated Cambridge Arch in Ohio, both developed above basement faults. Effects of movement in this fault zone are observed as syndepositional stratigraphic variations throughout the Paleozoic rock record. Especially noteworthy examples observed are: (1) in the Cambrian Copper Ridge Dolomite, where a channel sand, adjacent and parallel to the Cambridge Arch is thought to have been localized during syndepositional Cambrian activity; (2) in the many Silurian salts that have their western depositional limit adjacent to this fault zone, suggesting tectonic control of accumulation; and (3) in the Devonian Oriskany Sandstone that locally thickens on the crest of the Cambridge Arch, possibly as a sand bar accumulation on a paleotopographic high above the arch.

Another major zone of recurrent Paleozoic faulting has been traced from east of Pittsburgh to Cleveland, where it is termed the Highlandtown-Middleburg Fault Zone. Reactivation of the zone during deposition of Cambrian to Pennsylvanian strata has been noted. Regional thickness variations in the Silurian Clinton Sandstone and local structural control of Mississippian Berea Sandstone production associated with this zone are of particular interest.

Exploration for future petroleum reserves, especially for deeper prospects, is enhanced by deciphering regional tectonic heredity. The role of basement tectonics in syndepositional development of reservoirs and traps and postdepositional generation of structural traps is significant in Ohio.