Glossary of Karst and Cave Terms
carbonic acid dissolution
Dissolution of calcium carbonate by carbon dioxide in aqueous solution, loosely termed carbonic acid, is the dominant reaction in karst processes, including speleogenesis. The reaction can be considered in several ways but it is most simply represented as: CaCO3 + CO2 + H2O = Ca(HCO3)2 The reaction is reversible. The solution containing the dissolved reaction product, usually termed calcium bicarbonate, can lose carbon dioxide to the atmosphere and precipitate calcium carbonate. This process is responsible for the development of speleothems underground and tufa or travertine at the surface .