Shear zone between the Inner Piedmont and Kings Mountain belts in the Carolinas

The Kings Mountain shear zone, which marks the boundary between the Inner Piedmont and Kings Mountain belts near the NC-SC state line, is a northeast-striking, steeply to moderately dipping zone of ductile mylonitic deformation and late-stage semibrittle deformation. The zone is at least 60 km long and is no more than a few hundred metres wide. It truncates rock units of both belts. The juxtaposition of two lithologically different terranes suggests that displacement may be considerable, probably on the order of kilometres. Inconclusive evidence suggests that the northwest (Inner Piedmont) side is upthrown. The Kings Mountain zone is one of several in the southern Appalachian Piedmont that were active during a Middle to Late Devonian (Acadian?) deformational event, and it may be part of a regional fault system extending from AL to VA. The Kings Mountain, Lowndesville, and Towaliga zones may be a single zone more than 550 km long. © 1981 Geological Society of America.