ABSTRACT: Structure and Stratigraphy of the Rome Trough

WALKER, DAN, TERENCE HAMILTON-SMITH, MARTIN C. NOGER, and JAMES A. DRAHOVZAL, Kentucky Geological Survey, University of Kentucky, Lexington, KY

Recent structural mapping in the Rome trough suggests a complex structure very different from the symmetric and laterally continuous

graben commonly depicted. Early and Middle Cambrian extension in the Rome trough of eastern Kentucky and western West Virginia resulted in half-grabens of alternating polarity and variable displacement. These half-grabens are bounded in the dip direction by normal faults trending west-southwest that are laterally continuous only on the order of tens of kilometers. Along strike, the Rome trough is laterally segmented by north-south-trending faults, commonly expressed as flexures in younger rocks, which show evidence of significant strike-slip displacement.

Systematic well-log correlations based on both dip sections and strike sections suggest that Rome trough stratigraphy is laterally discontinuous, reflecting the influence of the aforementioned structural segmentation. Comparison of subsurface lithologies in the Rome trough, discerned by log analysis and sample descriptions, with outcrop exposures of the allochthonous Cambrian sections of Tennessee suggests that Rome trough strata can be correlated with strata of the Valley and Ridge and Blue Ridge. We therefore propose that strata of the Rome trough be correlated (from base to top) with the upper Chilhowee Group, Shady Dolomite, Rome Formation, and Conasauga Group. Furthermore, we propose that the boundary between the uppermost Rome Formation and the overlying Conasauga Group be revis d upward. The adoption of this revision would require that many of the carbonate bodies within the upper part of the Rome trough sequence be assigned to the Rome Formation.

AAPG Search and Discovery Article #91013©1992 AAPG Eastern Section Meeting, Champaign, Illinois, September 20-22, 1992 (2009)