Karst Formation - Landscapes Carved by Water

Karst is limestone that features internal drainage. Most areas that have karst formations also have heavy rainfall and a thick bed of limestone with a lot of underground flowing water.

Dissolution caves are formed by dissolving limestone. These are generally the largest caves with the most interesting features, including some of the most interesting mineral deposits.

Water sets in pools on top of the islands. It percolates down through cracks in the rocks. It dissolves limestone as it goes, thus enlarging the cracks.

The sides of this "sink hole" erode and dissolve. If a sea cave happens to connect with this hole, the enlarging process is sped up by the action of the sea water.

Acid dissolves the mineral calcite which is the primary mineral in limestone. Pure water is not acidic and therefore doesn't dissolve limestone. However, the atmosphere contains carbon dioxide. As rain fall, it picks up some of this CO2 and becomes acidic. Due tothe biological activities involved in soil production, there are high levels of CO2 in the soil. When rain combines with soil, it therefore becomes more acidic.

U.S. Sulfate Deposition

U.S. Nitrate Deposition

U.S. pH Levels