Sinkhole - Cenote

Image: shallow bowl-shaped solutional doline in the area called RegionSchwäbische Alb (Swabian Jura), RegionGermany.

A doline, sink or sinkhole is a closed depression draining underground in karst areas. It can be cylindrical, conical, bowl- or dish-shaped. The diametre ranges from a few to many hundreds of meters.

The name doline comes from dolina, the Slovenian word meaning valley. So this was originally a colloquial Slovenian word which was used by the geologists to describe a geologic feature.

There are two different mechanisms for the forming of dolines:

Image: Cylindrical doline, the entrance to ShowcaveDunmore Cave, RegionIreland. Image by Mathias Duckeck.
Solution Dolines
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