The Valley and Ridge physiographic province comprises
the area between the Blue Ridge province on the east and the
Appalachian Plateau province on the west. The province consists
of Paleozoic carbonate and clastic rocks that were folded and
thrust faulted during the Alleghanian orogeny. The Appalachian Plateau
province consists of mostly flat lying to gently dipping upper
Paleozoic rocks, with the transition between these two provinces
typically being a gradual change from folded middle and upper
Paleozoic clastic rocks to flat lying upper Paleozoic rocks in the
south, to a faulted boundary in the north.