Identification, Characterization and Analysis of Wrench Related Faulting in Southwestern Warren County, Kentucky

摘要

Warren County, Kentucky is located south of the southern boundary of the Rough Creek Graben marked by the Pennyrile fault system. The Pennyrile fault system is a regional southwest-northeast trending fault system that extends into Kentucky from the Reelfoot rift zone. The Rough Creek fault system bounds the northern arm of the Rough Creek Graben and trends northwest-southeast also extending from the Reelfoot rift zone. The Rough Creek fault system is related to the Shawneetown fault system in southeastern Illinois and occupies the southern end of the Illinois Basin. The East Continent Rift Basin intersects the Rough Creek Graben near its Eastern terminus and is parallel and west of the Grenville front. The structure under investigation in this paper was discovered west of the town of Woodburn, Kentucky. In 1992, West Bay Exploration Company of Michigan conducted a seismic survey of the Woodburn area and produced a series of two-dimensional profiles of the subsurface extending down to the Precambrian basement. Analysis of these profiles revealed a number of u27pop-upsu27 or possible wrench-related structures that can be traced upward through faulting from the Precambrian basement through the Knox Group and into the Mississippian section. Recent analysis of well log, seismic, and Radar images indicate extensive faulting in the Woodburn area indicative of wrench-fault related activity. A convincing surface expression of the deeper structure can be discerned from Radar imaging, aeromagnetic, and topographic maps of the region. An anomalous concentration of sinkholes is also visible from topographic maps and is aligned parallel to the curvature of the wrench structure on its western, southern, and eastern flanks.Wrench faults and associated structures are known to be productive traps for petroleum. West Bay Exploration Company of Traverse City Michigan drilled the subject structure in 1993 but the borehole test proved negative. Nonetheless, a detailed analysis of the subsurface using GIS and related software should aid in developing a prospecting tool for exploration geologists and aid in understanding the characteristic geologic sections of the Rough Creek Graben.