11. The Contact Caves of Central Greenbrier County

Six major cave systems are developed along the eastern border of the basal Hillsdale Limestone (Greenbrier Group) and the underlying Maccrady Shale between the town of Lewisburg and Spring Creek in central Greenbrier County. The total combined surveyed passage is just over 128 km (80 miles). The Hole is the northernmost of the contact caves and drains north to Spring Creek. Ludington, McClung, Maxwelton Sink, Benedict, and Wades caves drain southwest to Davis Spring. These caves are developed in the lower section of the Hillsdale Limestone with many passages entrenched by vadose erosion by up to 12 m (40 ft) into the shale. Recharge is mostly from small surface streams that flow westward on the Maccrady Shale and sink at the contact with the limestone. The pattern of passages is typically dendritic with an overall trend sub-parallel to the regional strike. Folding and faulting influence passage orientation in some of the passages, but the perching effect of the underlying shale forces the conduits downward along the local dip.