Throughout the world karst landscapes vary from rolling hills dotted with sinkholes, as found in portions of the central United States, to jagged hills and pinnacle karst found in the tropics. The development of all karst landforms requires the presence of rock which is capable of being dissolved by surface water or ground water.
The term karst describes a distinctive topography that indicates dissolution (also called chemical solution) of underlying soluble rocks by surface water or ground water. Although commonly associated with carbonate rocks (limestone and dolomite) other highly soluble rocks such as evaporates (gypsum and rock salt) can be sculpted into karst terrain.
Understanding caves and karst is important because ten percent of the Earth’s surface is occupied by karst landscape and as much as a quarter of the world’s population depends upon water supplied from karst areas. Though most abundant in humid regions where carbonate rock is present, karst terrain occurs in temperate, tropical, alpine and polar environments. Karst features range in scale from microscopic (chemical precipitates) to entire drainage systems and ecosystems which cover hundreds of square miles, and broad karst plateaus.
Although karst processes sculpt beautiful landscapes, karst systems are very vulnerable to ground water pollution due to the relatively rapid rate of water flow and the lack of a natural filtration system. This puts local drinking water supplies at risk of being contaminated. In the mid 1980’s, flooding of caves in the highly populated area of Bowling Green, Kentucky, caused industrial waste to leak into the vast system of underground fissures polluting the ground water in local wells. Due to urban expansion millions of dollars is spent annually in the United States to repair damage to roads, buildings and other structures which are built on unstable karst surfaces.
The term karst describes a distinctive topography that indicates dissolution (also called chemical solution) of underlying soluble rocks by surface water or ground water. Although commonly associated with carbonate rocks (limestone and dolomite) other highly soluble rocks such as evaporates (gypsum and rock salt) can be sculpted into karst terrain.
Understanding caves and karst is important because ten percent of the Earth’s surface is occupied by karst landscape and as much as a quarter of the world’s population depends upon water supplied from karst areas. Though most abundant in humid regions where carbonate rock is present, karst terrain occurs in temperate, tropical, alpine and polar environments. Karst features range in scale from microscopic (chemical precipitates) to entire drainage systems and ecosystems which cover hundreds of square miles, and broad karst plateaus.
Although karst processes sculpt beautiful landscapes, karst systems are very vulnerable to ground water pollution due to the relatively rapid rate of water flow and the lack of a natural filtration system. This puts local drinking water supplies at risk of being contaminated. In the mid 1980’s, flooding of caves in the highly populated area of Bowling Green, Kentucky, caused industrial waste to leak into the vast system of underground fissures polluting the ground water in local wells. Due to urban expansion millions of dollars is spent annually in the United States to repair damage to roads, buildings and other structures which are built on unstable karst surfaces.
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