A cryptodepression is a depression in the Earth's surface that is below mean sea level, and which is filled by a

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

. The term is derived from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

word ("hidden") and depression.

Description

A cryptodepression is often the result of a rift valley or a glaciation. Such lakes are often long and narrow, and the surrounding landscape and the shore of the lake can be very steep.

Examples

Lago O'Higgins/San Martín has a surface elevation of 250 meters and a maximal depth of 836 meters, yielding a cryptodepression of 586 meters. * ''Glacial lakes and moraine-dammed lakes'': major prealpine lakes in Italy have cryptodepressions created by erosion. In other parts of the Alps, Swiss, Bavarian and Austrian lakes, cryptodepressions are not found because the lakes have significantly higher elevations. Glacial lakes creating cryptodepressions also occur in Norway, Chile, Argentina, Newfoundland, New Zealand, and Scotland. In North America, four of the five Great Lakes (all except Erie) and two of the Finger Lakes in New York, Cayuga Lake and Seneca Lake, are examples of cryptodepressions. Mälaren in Sweden was created by a different process; it had been an arm of the Baltic Sea as recently as the

Viking Age The Viking Age (about ) was the period during the Middle Ages when Norsemen known as Vikings undertook large-scale raiding, colonising, conquest, and trading throughout Europe and reached North America. The Viking Age applies not only to their ...

before being cut off from the sea by post-glacial rebound. * ''Rift valleys'': the deepest known cryptodepression on Earth is in Lake Baikal (–1200 m). Other notable examples include Lake Tanganyika and Lake Malawi in Africa's East African Rift.

References

{{geomorph-stub Depressions (geology) de:Depression (Geologie)