Voxel-Based Interpretation of a 3-D Seismic Data Volume from Jackson County, Ohio

Reuter, Justin and Doyle R. Watts
Department of Geological Sciences, Wright State University, Dayton, OH

We analyzed a migrated 3-D reflection seismic data set collected from Jackson County Ohio, using volume-based voxel visualization technology. Formation sculpting revealed topography on the Knox Unconformity associated with dim spots. We mapped two intersecting faults that form a V- shaped graben in the field area.

Adjusting the opacities of voxels in a time-slab centered on the Precambrian reflector revealed a drainage channel system incised on the Ohio Precambrian surface, approximately 1460 meters (4790 ft.) below sea level. Formation sculpting of the Precambrian surface produced an image of 100-meter (330 ft.) wide tributaries on the Precambrian unconformity joining to produce a 400-meter (1310 ft.) wide channel roughly parallel to the subsurface trend of the Grenville front beneath west-central Ohio. Broadening and splitting of the zero phase seismic wavelet that defines the Precambrian reflector reveals the channels. The seismic signature is due to thin bed interference effects caused by reflections at the boundary between the channel fill with the overlying Mount Simon Sandstone and the boundary with the underlying Precambrian surface. The seismic images, therefore, locate a new lithologic unit in the Ohio subsurface. The channels are older than the overlying Mt. Simon Sandstone and so must be at of least Middle Cambrian age. The channel morphology indicates flow in the direction of the Rome trough, approximately 60-km to the south, likely transporting sediment to that basin. Given the tiny volume of Ohio ampled by 3-D seismic methods, such buried channels must be common on the Precambrian surface.

AAPG Search and Discovery Article #90031©2004 AAPG Eastern Section Meeting, Columbus, Ohio, October 3-5, 2004