Glacial Erosional Landforms :They are deep, long and wide troughs or basins with very steep concave to vertically dropping high walls at its head as well as sides. They are simply a bowl-shaped depression formed due to the erosional activity of glaciers.
Glaciers
- A glacier is a huge mass of ice that moves slowly over land. The term “glacier” comes from the French word glace (glah-SAY), which means ice. Glaciers are often called “rivers of ice.”
- Glaciers normally assume the shape of a tongue, broadest at the source & becoming narrower downhill.
- Though glacier is not liquid, but it moves gradually under the continual pressure from the snow accumulated above.
- The rate of movement is greatest in the middle where there is little obstruction.
- The sides & bottom are held back by the frictions due to valley sides & valley floors.
Landforms
Cirque/Corrie
- Hollow basin cut into a mountain ridge.
- It has steep sided slope on three sides, an open end on one side and a flat bottom.
- When the ice melts, the cirque may develop into a tarn lake.
Glacial Trough
- Original stream-cut valley, further modified by glacial action.
- It is a ‘U’ Shaped Valley.
- It at mature stage of valley formation.
- Since glacial mass is heavy and slow moving, erosional activity is uniform – horizontally as well as vertically.
- A steep sided and flat bottomed valley results, which has a ‘U’ shaped profile.
Hanging Valley
- Formed when smaller tributaries are unable to cut as deeply as bigger ones and remain ‘hanging’ at higher levels than the main valley as discordant tributaries.
- A valley carved out by a small tributary glacier that joins with a valley carved out by a much larger glacier.
Arete
- Steep-sided, sharp-tipped summit with the glacial activity cutting into it from two sides.
Horn
- Ridge that acquires a ‘horn’ shape when the glacial activity cuts it from more than two sides.
Glacial Erosional Landforms
Read more : Wind Eroded Landforms
