Structural Geology of Northwestern Ohio

Lawrence H. Wickstrom, John D. Gray

Recently developed structure contour maps for the Cambrian and Ordovician strata show the northwestern Ohio area to be much more structurally complex than previously noted. These new maps illustrate several new faults and structural trends. Analysis of these faults indicates that northwestern Ohio is broken by a series of wrench faults, with associated folding. Vertical displacement is noted along some of these wrench faults.

Fault-plane solutions from this area reveal a dominant compressive stress direction from the southeast. This stress orientation would be consistent with those generated during the Taconic orogeny. Timing indicators from seismic analysis reveal one episode of faulting occurred shortly after deposition of the Trenton Limestone. At least one episode of movement has occurred since that time, as evidenced by displacement within the Silurian bedrock. Furthermore, seismic, gravity, and magnetic surveys indicate that preexisting weaknesses within the Precambrian may have influenced the position of many of the structural features noted.

AAPG Search and Discovery Article #91041©1987 AAPG Eastern Section Meeting, Columbus, Ohio, October 7-10, 1987.