Meso-scale fault surfaces that transect bedding and have sub-horizontal slip lineations are found throughout the Valley and Ridge province, but are specifically concentrated in the western and central part of the province. Fault surfaces commonly have slip lineations parallel to the fault-bedding intersection, indicating pre-folding horizontal fault slip. Later syn-folding fault slip is indicated by slip lineations that are at an angle to the fault-bedding intersection. These occasionally are found to overprint the earlier slip lineations. The latest episode of fault motion is post-folding, indicated by slip lineations that are horizontal. Most of the slip lineations reflect right-lateral slip, with left-lateral slip less common. Where both right- and left-lateral slip surfaces are present in an outcrop they are interpreted to define a shear couple bisected by the principle shortening direction. In the 030°-striking part of the Valley and Ridge, the faults record ~W to WNW-directed shortening, while in the central part of the salient, the shortening direction is NNW to N.

The much larger Latitude 40° N fault zone or Transylvania Fracture zone also has a right-lateral slip sense. Detailed field mapping and structural analysis this large fault system shows a complex fault movement history that spans the folding history of the Valley and Ridge province. As detailed by previous workers, the mapped east-west trending fault system extends across the Valley and Ridge province to, but not into Plateau province. To the east, the right lateral tear-fault system consists of two discrete faults: the Sideling Hill fault with >500 m of horizontal displacement and the Breezewood fault with at least ~900 m of horizontal displacement. To the west, displacement is concentrated along a complex, 3 km wide system of smaller faults. Rocks containing fault-related rotated beds, disrupted bedding, minor splay faults, and enhanced fracturing occur up to 1000 m from the mapped fault traces. The regional fold pattern varies significantly across the fault system, indicating differential displacement in the duplex above the Ordovician Martinsburg detachment.

      The lateral displacement faults are interpreted to have accommodated the WNW-directed emplacement of the Blue Ridge massif and the NNW-directed emplacement of the Reading Prong massif during the late Alleghanian orogeny.