BRITTLE AND DUCTILE DEFORMATION ALONG THE CHARLOTTE/CAROLINA TERRANE BOUNDARY IN 6 QUADRANGLES IN CENTRAL SOUTH CAROLINA

Field mapping in 6 contiguous quadrangles (Rabon Crossroads, Longtown, Ridgeway, Winnsboro Mills, Rion, and Chapin) in central SC along the boundary between the Charlotte and Carolina terranes has revealed a complex history of brittle and ductile deformation on a regional scale. The boundary between high-grade felsic gneisses and amphibolites in the Charlotte terrane (formerly Charlotte belt), and low-grade metavolcanic and metasedimentary rocks in the Carolina terrane (formerly Carolina slate belt) is a kilometer-scale ductile shear zone with dextral offset. The shear zone and terrane boundary appear to dip south at a shallow rate beneath the Carolina terrane. Map-scale brittle faults trend both parallel and perpendicular to the shear zone and are revealed by outcrops of siliceous breccia or by abrupt changes in lithology along strike. The entire area has been warped into broad plunging folds. Portions of the terrane boundary are at or near areas of gold mineralization in the Carolinas and some of the deformation may be related to gold occurrence.