Sinkhole

The Red Lake sinkhole in Croatia

A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water enters into underground passages known as ponor, swallow hole or swallet.[1][2][3][4] A cenote is a type of sinkhole that exposes groundwater underneath.[4] Sink, and stream sink are more general terms for sites that drain surface water, possibly by infiltration into sediment or crumbled rock.[2]

Most sinkholes are caused by karst processes – the chemical dissolution of carbonate rocks, collapse or suffosion processes.[1][5] Sinkholes are usually circular and vary in size from tens to hundreds of meters both in diameter and depth, and vary in form from soil-lined bowls to bedrock-edged chasms. Sinkholes may form gradually or suddenly, and are found worldwide.[2][1]

  1. ^ a b c Williams, Paul (2004). "Dolines". In Gunn, John (ed.). Encyclopedia of Caves and Karst Science. Taylor & Francis. pp. 628–642. ISBN 978-1-57958-399-6.
  2. ^ a b c Kohl, Martin (2001). "Subsidence and sinkholes in East Tennessee. A field guide to holes in the ground" (PDF). State of Tennessee. Archived from the original (PDF) on 14 July 2015. Retrieved 18 February 2014.
  3. ^ Thomas, David; Goudie, Andrew, eds. (2009). The Dictionary of Physical Geography (3rd ed.). Chichester: John Wiley & Sons. p. 440. ISBN 978-1444313161.
  4. ^ a b Monroe, Watson Hiner (1970). "A glossary of Karst terminology". U.S. Geological Survey Water Supply Paper. 1899-K. doi:10.3133/wsp1899k.
  5. ^ "Caves and karst – dolines and sinkholes". British Geological Survey.