What is a lake

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What is a lake?
Depression the lake BASIN
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Origin of lake basins
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I. Tectonic basins
Graben Lakes

• Changes in sea level uplift lakes

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II. Volcanic origin

• A. Filling of a caldera

B. Lava dam or mud flow
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III. Lakes formed by ice

• A. Morainic Impoundment

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• Tarn -- a small morainic impoundment, usually
  high in the mountains, at the base of a glacier
  or in the cirque where a glacier was.
• Paternoster lakes -- a series of morinic
  impoundments formed by the advance and retreat of
  a glacier

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B. Kettle Lakes (or prairie potholes)
C. Glacial scour lakes
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D. Cryogenic lakes
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IV. Solution basins

• Formed by the dissolution of bedrock in an area
  of carbonate rock (e.g., limestone) when a
  sinkhole connects to underground water.

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V. Landslides

• Landslide dams up a valley -- often temporary

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VI. Fluviatile lakes

• Lakes formed by rivers
• Ponding by tributary sediments
• Oxbow lakes -- in floodplain

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VII. Deflation basins
VIII. Meteoric origin
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IX. Animal origin

• Beaver dams

Reservoirs
Human impoundment