Question

Sinkholes are formed by the actions of

Answer 1

Sinkholes mainly occur in what is known as 'karst terrain'; areas of land where soluble bedrock (such as limestone or gypsum) can be dissolved by water. With cover-subsidence sinkholes the bedrock becomes exposed and is gradually worn down over time, with the holes often becoming ponds as the water fills them in.

Answer 2

Sometimes, heavy weight on soft soil can result in collapse of ground, resulting in asinkhole. Sinkholes can also form when the land surface is changed. Areas that have a bedrock made of limestone, salt deposits or carbonate rock are most susceptible to erosion and the formation of such holes.