Cirque:
- A cirque ("serk") is a bowl-shaped rock valley on the side of a mountain, often with a glacier or permanent snowfield in it.
- Cirques are created by glaciers, grinding an existing valley into a rounded shape with steep sides.
- The back wall of the cirque is like a high cliff and the floor is concave and huge in size. The total shape resembles an armchair.
- When a glacier melts completely, water accumulates in the cirque and forms a lake which is known as a tarn.
U-shaped valley:
- When a glacier is flowing through a valley in a mountainous region, the sides of the valley get eroded. Ice causes friction on the sides of the valley.
- As the erosion of the sides is greater than that of the floor, a valley is formed with vertical sides and a wide floor. This valley is called a U-Shaped valley.
Hanging Valley:
- Hanging valleys are often associated with valley glaciers, joining the main valley along its sides.
- They are the product of different rates of erosion between the main valley and the valleys that enter it along its sides.
- The tributaries are left high above the main valley, hanging on the edges, their rivers and streams entering the main valley by either a series of small waterfalls or a single impressive fall.
Fjord:
- Steep-sided narrow entrance-like feature at the coast where the stream meets the coast.
- Fjords are common in Norway, Greenland and New Zealand.
Moraine
- The material transported and deposited by a glacier is known as moraine.
- Moraine is made up of pieces of rocks that are shattered by frost action and are brought down by river.
- Zigzag hills, with many steeps slopes, made up of long stretches of sand and gravel are called eskers.
- The oval shaped hills of lesser height are called drumlins.
Types of moraine;
- Lateral
- Medial
- Terminal
- Ground
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