NEW FIELD EVIDENCE FOR AN EXPOSURE OF THE APPALACHIAN DECOLLEMENT AT THE EAST-END OF THE PINE MOUNTAIN TERRANE, GEORGIA

Detailed held mapping at the east end of the Pine Mountain terrane in central Georgia indicates that the Box Ankle fault is an similar to 4- km-thick ductile shear zone separating Grenvillian basement of Laurent ian affinity in the footwall from allochthonous accreted terranes in t he hanging wall. Fabric data from the Box Ankle fault indicate that it is a gently southeast dipping, northwest-vergent thrust fault. Recent ly discovered structural relations, together with geochronological dat a, indicate that the Box Ankle fault is of late Paleozoic age. We argu e that the Box Ankle fault is a surface exposure of the Appalachian de collement. The east end of the Pine Mountain terrane may be the only p lace in the entire orogen where this fundamentally important structure is exposed for study.