"Karst terrain" means a terrain, generally underlain by limestone or dolomite, in which the topography is formed chiefly by the dissolving of rock and which may be characterized by sinkholes, sinking streams, closed depressions, subterranean drainage, and caves. The principal karst-forming carbonate rocks in West Virginia are within the Mississippian Greenbrier Group; Devonian and Silurian Helderberg Group and Tonoloway Limestone; and Ordovician and Cambrian Black River Group, Saint Paul Group, Beekmantown Group, Conococheague Formation, Elbrook Formation, and Tomstown Dolomite. Based on recent geologic mapping in southern West Virginia, the Mississippian Avis Limestone, also known as the Little Stone Gap, can be added to this list.
The map below shows the outcrop of these carbonate units and the tax districts in which the outcrops occur. It is based on publications of this agency as well as field observations by experienced Geological and Economic Survey geologists who have conducted detailed geologic mapping in the state. The only publically—available source of cave locations in West Virginia is West Virginia Geological and Economic Survey Volume 19A by William E. Davies, titled "Caverns of West Virginia."1 It was first published in 1949, revised and reprinted in 1958, and reprinted with supplement in 1965. The map shows locations of caves from Volume 19A observed within the carbonate outcrop area. Despite the fact that Davies’ locations were somewhat generalized, they fall on the bands of carbonate outcrop.
Davies book also lists cave locations in other parts of the state, but they are for the most part isolated, very small, in some cases “shelter” caves, or formed in sandstone, and are not part of a karst terrain. Thin marine limestones occur in the coal measures, but where these units crop out in the northern part of the state, isolated caves are few in number and small in size. Similarly, an outcrop of the Greenbrier Limestone occurs in Webster County near Webster Springs, but it is very limited in areal extent and not included in the map.
Therefore, this map identifies those districts that contain outcrops of geological units exhibiting the characteristics of karst, including caves and sinkholes.
1 Davies, William E., Caverns of West Virginia, (Volume 19A): Davies, William E., Caverns of West Virginia, (Volume 19A): http://www.wvgs.wvnet.edu/wvges2/publications/PubCat_Details.aspx?PubCatID=V-19A