Karst is a geological phenomenon, first described in Slovenia. This area is called Kras or Karst, which means rocky place. Since then all areas with a similar geological situation are called Karst Areas.
The basic aspects of karst areas are soluble bedrock, cracks and water. The rain water is able to solute small amounts of rock and carry them away. Most rocks are not permeable to water, but sediments have horizontal layers Additionaly, during times of up- and downlift, the layers got mostly vertical cracks. When water follows the cracks, it dissolves the rock and forms caves and caverns.
Common rocks for karst areas all over the world are:
There are caves in other kind of rock, but they are not karst features! Typical features of karst areas are:
The type of erosional forms which the karst takes, depends on many variables: