Glaciation

Question 1

Formation of a cirque

Answer 1

Snow collects in a mountain hollow, high in the mountain. Snow compacts + forms ice. A glacier is born.
Through plucking and abrasion, the hollow grows deeper +widens. Freeze-thaw action occurs
When the glacier overflows, it moves downslope as a glacier
When the glacier melts, a tarn may be trapped in the cirque hollow.
When 2 cirques are back to back, the ridge between them is known as an arête

Question 2

plucking

Answer 2

As ice moves, friction happens between ice+the ground. Friction increases, causing the ice at the base to melt. The meltwater moves onto the cracks, freezing around the rocks. When the ice moves again it plucks the rock from the ground.

Question 3

Abrasion

Answer 3

Plucked rocks become embedded at the base of the glacier. As the glacier moves the rocks abrade the surface over which they move

Question 4

glaciated valley

Answer 4

A v-shaped valley straightened+flattened by a big glacier to become a U-shaped valley

Question 5

Cirque/corrie

Answer 5

A large hollow on the side of a mountain. It has 3 steep sides + is the birthplace of a glacier

Question 6

Tarn

Answer 6

A lake inside of a cirque

Question 7

Pyramidal peak

Answer 7

Steep sided mountain eroded on all sides by many cirques. E.g., Carantoohill, Kerry

Question 8

Arête

Answer 8

A narrow steep-sided ridge, between 2 cirques

Question 9

Paternoster lakes

Answer 9

Several linked ribbon lakes. A ribbon long narrow lake that occupies the floor of a glaciated valley

Question 10

truncated spur

Answer 10

An interlocking spur that was eroded, having its head cut off as the glacier moved through the valley

Question 11

Hanging valley

Answer 11

A small tributary valley that hangs above the main glaciated valley