Karst is most strongly developed in dense carbonate rock, such as limestone, that is thinly bedded and highly fractured. Karst is not typically well developed in chalk, because chalk is highly porous rather than dense, so the flow of groundwater is not concentrated along fractures.

Karst is a landscape shaped by the erosion of limestone. The karst landscape of Shilin was formed about 270 million years ago. Karst is an area of land made up of limestone. Limestone, also known as chalk or calcium carbonate, is a soft rock that dissolves in water.

Features such as lapiés, natural bridges, and pepino hills are characteristic of karsts. If a cave becomes large enough and the top extends close enough to the surface, the top collapses. This produces depressions called sinkholes, which are among the most characteristic features of karst topography.

Rocks especially susceptible to the development of karst topography are those containing a high amount of the mineral calcite, such as LIMESTONE. Through time, chemical weathering along some of these pathways of ground water has dissolved and removed rock material. These voids are called CAVERNS.

Karst is a type of landscape where the dissolving of the bedrock has created sinkholes, sinking streams, caves, springs, and other characteristic features. Karst is associated with soluble rock types such as limestone, marble, and gypsum.

[ kärst ] A landscape that is characterized by numerous caves, sinkholes, fissures, and underground streams. Karst topography usually forms in regions of plentiful rainfall where bedrock consists of carbonate-rich rock, such as limestone, gypsum, or dolomite, that is easily dissolved.

Consequently, most karst regions develop in areas where the bedrock is limestone. Karst regions occur mainly in the great sedimentary basins. The United States contains the most extensive karst region of the world. The Mammoth cave system is located in this area.

The collapse of bedrock into underlying cavities is one of the most serious and common hazards in karst areas. Although large collapse sinkholes are known from many karst terrains in the world, the largest and most spectacular, called tiankeng (sky holes), occur in tropical karst (Ford and Williams, 2007).

Karst development is strongly influenced by climate, both directly (via the moisture balance and temperature regime) and indirectly. The indirect effects include biogeomorphic impacts of biota, and base level changes associated with sea-level and river incision or aggradation.

Many karst terrains make beautiful housing sites for urban development. However, since people have settled on karst areas, many problems have developed; for example, insufficient and easily contaminated water supplies, poor surface water drainage, and catastrophic collapse and subsidence features.

A circular hole typically forms and grows over a period of minutes to hours. Slumping of the sediments along the sides of the sinkhole may take approximately a day’s time to stop. In the less catastrophic cover subsidence type of sinkhole, sediments slowly settle into underground voids in the bedrock.