Karst Topography in the Appalachian Plateau

Karst topography, which is characterized by limestone rocks and caves,is not widely distributed. However, near the escarpments of the Cumberland Plateau, evidence of solution of carbonates beneath clastic rocks becomes apparent. In a few places, deep sinkholes have formed with walls of clastic rock, apparently resulting from collapse of underlying voids formed bydissolving of the underlying carbonates. Even more common are cave entrances along the escarpments, owing to the cropping out of carbonate units. These entrances may be abundant, even though sinkholes in the same area may be rare (for example see Shofer and others 2001). Crawford (1984) has propounded a model for retreat of the escarpments in which conduit caves form by subterranean invasion of surface streams resulting from faster chemical erosion of underlying carbonates. As these caves enlarge, the escarpment is eroded from within and retreats.