The ductile parts of some terrane dispersal-related strike-slip faults may be exposed as Alleghanian shear zones in the southern Appalachian Piedmont. Mesoscopic structures in the Brevard fault zone, Central Piedmont suture, and Eastern Piedmont fault system all indicate dextral strike slip on moderately to steeply dipping shear zones. Seismic reflection profiles suggest that some of the shear zones flatten at depth and merge with subhorizontal detachments in the middle crust. I propose that the listric geometry of the Alleghanian structures reflects strike slip on resurrected subhorizontal detachments that were established in earlier Paleozoic collisions or in an earlier part of the Alleghanian orogeny.

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