Karst is where the caves are. The word "karst" refers to a type of terrain, usually formed on carbonate rock (limestone and dolomite) where groundwater has solutionally enlarged or dissolved openings to form an underground drainage system. A mild carbonic acid produced from carbon dioxide in the atmosphere, particularly in the soil atmosphere, is primarily responsible for the solvent power of groundwater on carbonate rocks.
Over millions of years, as the route of the water underground is enlarged, These underground streams change from lightly moving water through small openings, to heavy flowing, turbulent conduit systems with discharge points at springs. As the water table lowers below the level of surface streams, the streams begin to lose water to developing cave systems underground. As more and more surface water is diverted underground, surface stream valleys virtually disappear and are replaced by closed basins called sinkholes. Sinkholes vary from small cylindrical pits to large conical or parabolic basins that collect and funnel runoff into underground streams.
Because of the nature of karst areas, they are extreemly sensitive to groundwater contamination and pollution. Other problems include sinkhole flooding and sinkhole collapse.
Karst areas in Indiana are mainly within two areas south of the Wisconsin glacial boundry. These karst areas are characterized by sinkholes, sinking streams, and caves. The smaller of the two karst areas includes parts of Clark, Decatur, Jefferson, Jennings, and Ripley Counties. The larger includes parts of Putnam, Owen, Morgan, Monroe, Greene, Lawrence, Martin, Orange, Washington, Crawford, Harrison, and Perry Counties.
The Karst Pages
Cave and Karst Terminology