ii. Landforms Made By Glaciers
A large mass of ice moving very slowly through a valley or spreading outward from a centre is called a glacier. The movement of glaciers is slow, unlike water flow. Erosion by glaciers is tremendous because of friction caused by the sheer weight of the ice.
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Erosional Landforms |
Depositional Landforms |
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1. Cirque – They are deep, long, and wide troughs or basins with very steep concave to vertically dropping high walls at their head as well as sides. 2. Horns and serrated Ridges – If three or more radiating glaciers cut headward until their cirques meet, high, sharp-pointed, and steep peaks called horns form. 3. Glacial valleys/Troughs – Very deep glacial troughs filled with seawater and making up shorelines are called fiords. 4. Others – hanging valleys, Bergschrund, etc. |
The unsorted coarse and fine debris dropped by the melting glaciers is called glacial tills. 1. Marines – Moraines are long ridges of deposits of glacial till. Deposits are at the end of a glacier – Terminal moraines Deposits on both sides – Lateral moraines. 2. Eskers – Eskers are meandering ridges of sediment that form in water channels beneath or within the glacier ice. The floors of these channels can be rock, sediment, or ice. 3. Outwash plain – assorted roughly stratified deposits. 4. Drumlins – Drumlins are smooth oval shaped ridge-like features composed mainly of glacial till along with some masses of gravel and sand. |