Iceberg Cirque in Glacier National Park, USA

The Lower Curtis Glacier, North Cascades National Park, is a well developed cirque glacier. If the glacier continues to retreat and melt away, a lake may form in the basin.

A cirque is an amphitheatre-like valley (or valley head) of glacial origin, formed by glacial erosion at the head of the glacier. Cirques are typically partially surrounded by steep cliffs. The highest cliff is often called a headwall. They are also known as a cwm in Wales, a coomb or coombe in England, and a corrie in Scotland and Ireland. Download high resolution version (1024x768, 137 KB)Photo of Iceberg Cirque, courtesy Glacier National Park, US National Park Service. ... Download high resolution version (1024x768, 137 KB)Photo of Iceberg Cirque, courtesy Glacier National Park, US National Park Service. ... The Iceberg Cirque is a large cirque that has been carved out by glaciation. ... There is also a non-adjoining national park by the same name in British Columbia. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixel Image in higher resolution (2048 × 1536 pixel, file size: 692 KB, MIME type: image/jpeg) The Lower Curtis Glacier, North Cascades, WA in 2004. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixel Image in higher resolution (2048 × 1536 pixel, file size: 692 KB, MIME type: image/jpeg) The Lower Curtis Glacier, North Cascades, WA in 2004. ... Looking toward Magic Mountain from the Cascade Pass trail North Cascades National Park is a U.S. National Park located in Washington state. ... A cirque glacier is formed in cirque, bowl-shaped depressions on the side of mountains. ... The Colosseum in Rome, Italy. ... Fljótsdalur in East Iceland, a rather flat valley A valley (in Scotland, a glen) is a landform, which can range from a few square miles (square kilometers) to hundreds or even thousands of square miles in area. ... A glacier is a large, persistent body of ice, formed largely of compacted layers of snow, that slowly deforms and flows in response to gravity. ... Severe soil erosion in a wheat field near Washington State University, USA. For erosion as understood by materials science, see Erosion (materials science) For erosion as an English analogy, see Erosion (figurative) For erosion as an operation of Mathematical morphology, see Erosion (morphology) Erosion is the displacement of solids (soil... “Precipice” redirects here. ... A headwall is the name given to the highest cliff in a glacial cirque. ... This article is about the country. ... A coombe or (variant spellings) coomb, combe or cwm is a short valley or hollow on a hill or coastline. ... Motto: (French for God and my right) Anthem: God Save the King/Queen Capital London (de facto) Largest city London Official language(s) English (de facto) Unification    - by Athelstan AD 927  Area    - Total 130,395 km² (1st in UK)   50,346 sq mi  Population    - 2006 est. ... It has been suggested that Coombe be merged into this article or section. ... Motto (Latin) No one provokes me with impunity Wha daur meddle wi me?(Scots)1 Anthem (Multiple unofficial anthems) Scotlands location in Europe Capital Edinburgh Largest city Glasgow Official languages English, Gaelic, Scots3 Government Constitutional monarchy  -  Queen Queen Elizabeth II  -  Prime Minister Tony Blair MP  -  First Minister Jack McConnell...

Many glacial cirques contain tarns dammed by either till or a bedrock threshold. Cirques form in conditions which are favorable; which in the northern hemisphere includes the north-east slope being in shade and away from prevailing winds. These areas are sheltered from heat, and so, they encourage the accumulation of snow. Triad Lake in Glacier Peak Wilderness View of Tarn Hows, Cumbria A tarn (or corrie loch) is a mountain lake or pool, formed in a corrie excavated by a glacier. ...

Cirques form in conditions which are favorable for glacier formation - where snow can accumulate into a thick and large mass. Animation of snowcover changing with the seasons Trees covered with snow Snow is a source of precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. ...

If the accumulation of snow increases, the snow transforms into glacial ice. The process of nivation follows (where a hollow in a slope may be enlarged by freeze-thaw weathering and glacial erosion). Eventually, this hollow can become big enough so that glacial erosion intensifies. Debris (or till) in the ice may also abrade (glacial abrasion) the bed surface; should ice move down a slope it would have a ‘sandpaper effect’ on the bedrock beneath on which it scrapes. Nivation is the process of alternative freeze and thaw by which fallen snow gets converted into mass of ice or Névé, hence the term, nivation. ... Weathering is the process of breaking down rocks, soils and their minerals through direct contact with the atmosphere. ... Glacially abraded rocks in western Norway near Jostedalsbreen glacier. ... Bedrock is the native consolidated rock underlying the Earths surface. ...

Eventually, the hollow can become a large bowl shape in the side of the mountain, with the headwall being weathered by constant freezing and thawing, and eroded by plucking. The basin will become deeper if it continues to become eroded by abrasion. Should plucking and abrasion continue, the dimensions of the cirque will increase, but the proportion of the landform would remain roughly the same. A salad in a bowl sits next to a small pie in a pie dish Chawan, drinking bowls used in a Japanese tea ceremony Bowls used as construction tools in contemporary India. ... Plucking, in the sense relating to glaciers, is when a glacier erodes away chunks of bedrock to be later deposited as erratics. ...

If two adjacent cirques erode toward one another, an arête, or steep sided ridge, forms.
Should three or more cirques erode toward one another, a pyramidal peak or glacial horn would be created. The Garden Wall, an arête in Glacier National Park (U.S.) An arête is a thin, almost knife-like, ridge of rock which is typically formed when two glaciers erode parallel U-shaped valleys. ... The Matterhorn, a classic peak A pyramidal peak, or sometimes in its most extreme form called a glacial horn, is a mountaintop that has been modified by the action of ice during glaciation and frost weathering. ... A glacial horn (or, if unambiguous from context, simply a horn) is a mountain formed by glacial erosion. ...

Notable cirques

• Great Basin, Maine, United States
• Iceberg Cirque, Montana, United States
• Cirque de Navacelles, France
• Cirque of the Towers, Wyoming, United States
• Tuckerman Ravine, New Hampshire, United States
• Śnieżne Kotły, Karkonosze Mountains, Poland
• Chandra Taal, Himachal Pradesh, India

Official language(s) None (English de facto; French is also an administrative language) Capital Augusta Largest city Portland Area  Ranked 39th  - Total 33,414 sq mi (86,542 km²)  - Width 210 miles (338 km)  - Length 320 miles (515 km)  - % water 13. ... The Iceberg Cirque is a large cirque that has been carved out by glaciation. ... Official language(s) English Capital Helena Largest city Billings Area  Ranked 4th  - Total 147,165 sq mi (381,156 km²)  - Width 255 miles (410 km)  - Length 630 miles (1,015 km)  - % water 1  - Latitude 44°26N to 49°N  - Longitude 104°2W to 116°2W Population  Ranked... An ariel satalitte photo showing the valley, as the river cut through it. ... Cirque of the Towers U.S. Geological Survey The Cirque of the Towers is located in the Wind River Range Wyoming, U.S. part which is in the Bridger Wilderness in Bridger-Teton National Forest, while the remainder is in the Popo Agie Wilderness in Shoshone National Forest. ... Official language(s) English Capital Cheyenne Largest city Cheyenne Area  Ranked 10th  - Total 97,818 sq mi (253,348 km²)  - Width 280 miles (450 km)  - Length 360 miles (580 km)  - % water 0. ... Tuckerman Ravine viewed from the Boott Spur Trail Tuckerman Ravine (called casually Tucks) is a glacial cirque sloping down eastward on the southeast face of Mt. ... Official language(s) English Capital Concord Largest city Manchester Area  Ranked 46th  - Total 9,359 sq mi (24,239 km²)  - Width 68 miles (110 km)  - Length 190 miles (305 km)  - % water 3. ... Aerial view over Karkonosze Karkonosze (Polish name, pronounced kár-ko-no-she; Krkonoše in Czech; Riesengebirge in German) or Giant Mountains are part of the Sudetes Mountains in central Europe. ... Chandra Taal is a lake in the Himalayas at an altitude of about 4500 meters. ... Himachal Pradesh   (Hindi: हिमाचल प्रदेश, IPA: ), formerly the Punjab Hill States, is a mostly mountainous state in northern India. ...

See also

• Glacial landforms