In the UK there are rocks that dissolve including limestone, chalk (a form of limestone) gypsum (the raw material for plaster) and salt. Rainfall and the resultant flow of water underground can dissolve these rocks over time to form caves and underground cavities. Although generally stable, these cavities can collapse either naturally or because of man-made changes to the surface and underground drainage, for example by water abstraction or leaking pipes. When this happens buildings and other structures can suffer subsidence. Dissolution can also make the buried rock surface very irregular with hollows filled with soft deposits, which can also cause subsidence. It is important to avoid the most subsidence prone areas and to investigate then design development to cope with potential problems.
Distribution of soluble (karstic) rocks in the Great Britain.
For further information about the Dissolution Hazards Project contact: enquiries