This article needs additional citations for verification. (December 2009) (Learn how and when to remove this template message)
In geology, a proglacial lake is a lake formed either by the damming action of a moraine or ice dam during the retreat of a melting glacier, or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ice. At the end of the last ice age approximately 10,000 years ago, large proglacial lakes were a widespread feature in the northern hemisphere.
In some cases, such lakes gradually evaporated during the warming period after the Quaternary ice age. In other cases, such as Glacial Lake Missoula and Glacial Lake Wisconsin in the United States, the sudden rupturing of the supporting dam caused glacial lake outburst floods, the rapid and catastrophic release of dammed water resulting in the formation of gorges and other structures downstream from the former lake. Good examples of these structures can be found in the Channeled Scablands of eastern Washington, an area heavily eroded by the Missoula Floods.
In Great Britain, Lake Lapworth, Lake Harrison and Lake Pickering were examples of proglacial lakes. Ironbridge Gorge in Shropshire and Hubbard's Hills in Lincolnshire are examples of a glacial overspill channel created when the water of a proglacial lake rose high enough to breach the lowest point in the containing watershed.
The receding glaciers of the tropical Andes have formed a number of proglacial lakes, especially in the Cordillera Blanca of Peru, where 70% of all tropical glaciers are. Several such lakes have formed rapidly during the 20th century. These lakes may burst, creating a hazard for zones below. Many natural dams (usually moraines) containing the lake water have been reinforced with safety dams. Some 34 such dams have been built in the Cordillera Blanca to contain proglacial lakes.
Ice Dammed Lakes
|Flood/River||Location||Date||Peak discharge(106 m3/s)||Reference|
|Kuray||Altai, Russia||Late Pleistocene||18||Baker et al., 1993|
|Missoula||Northwestern USA||Late Pleistocene||17||O'Connor and Baker, 1992|
|Darkhat Lakes||Mongolia||Late Pleistocene||4||Rudoy, 1998|
|Jassater Lakes||Altai, Russia||Late Pleistocene||2||Rudoy, 1998|
|Yaloman Lakes||Altai, Russia||Late Pleistocene||2||Rudoy, 1998|
|Ulymon Lakes||Altai, Russia||Late Pleistocene||1.9||Rudoy, 1998|
|Lake Regina||Canada/USA||Late Pleistocene||0.8||Lord and Kehew, 1987|
|Wabash River||Indiana, USA||Late Pleistocene||0.27||Vaughn and Ash, 1983|
|Lake Agassiz||Canada/USA||Late Pleistocene||0.13||Matsch, 1983|
|Porcupine River||Alaska, USA||Late Pleistocene||0.13||Thorson, 1989|
|Russell Fiord||Alaska, USA||1986||0.10||Mayo, 1989|
- http://www.cr.nps.gov/history/online_books/geology/publications/inf/72-2/sec5.htm USGS The Channeled Scablands of Eastern Washington
- O’Connor, J.E., and Costa, J.E., 2004, The world’s largest floods, past and present—Their causes and magnitudes: U.S. Geological Survey Circular 1254, 13 p.
- Baker, V.R., Benito, G., and Rudoy, A.N., 1993. Paleo-hydrology of late Pleistocene superflooding, Altay Mountains, Siberia: Science, 259, p. 348–350.
- Lord, M.L., and Kehew, A.E., 1987, Sedimentology and paleohydrology of glacial-lake outburst deposits in southeastern Saskatchewan and northwestern North Dakota: Geological Society of America Bulletin v. 99, p. 663–673.
- Matsch, C.L., 1983, River Warren, the southern outlet of Glacial Lake Agassiz, in Teller, J.T., and Lee, Clayton, Glacial Lake Agassiz: Geological Association of Canada Special Paper 26, p. 231–244.
- Mayo, L.R., 1989, Advance of Hubbard Glacier and 1986 outburst of Russell Fiord, Alaska, U.S.A.: Annals of Glaciology, v. 13, p. 189–194.
- O'Connor, J.E., and Baker, V.R., 1992, Magnitudes and implications of peak discharges from Glacial Lake Missoula: Geological Society of America Bulletin, v. 104, p. 267–279.
- Rudoy, A., 1998, Mountain ice-dammed lakes of southern Siberia and their influence on the development and regime of the intracontinental runoff systems of North Asia in the late Pleistocene, in Benito, G., Baker, V.R., and Gregory, K.J., eds., Paleohydrology and Environmental Change: John Wiley and Sons, p. 215–234.
- Thorson, R.M., 1989, Late Quaternary paleofloods along the Porcupine River, Alaska—Implication for regional correlation, in Carter, L.D., Hamilton, T.D., and Galloway, J.P., eds., Late Cenozoic history of the interior basins of Alaska and the Yukon: U.S. Geological Survey Circular 1026, p. 51–54.
- Vaughn, D., and Ash, D.W., 1983, Paleohydrology and geomorphology of selected reaches of the upper Wabash River, Indiana: Geological Society of America Program with Abstracts, v. 15, no. 6, p. 711.
|This glaciology article is a stub. You can help Wikipedia by expanding it.|