On this page:

• Glaciation
• Glacial Erosion

Glaciation
Glaciation is the study of ice and its impact on the environment.
The Ice Age in Britain lasted from about one million years ago to about 20 000 years ago. During that time the Northern and Eastern parts of the British Isles were covered in ice. Glaciers were formed which move down valleys with great erosive power. These glaciers carved new scenery.

Glacial Erosion
There are three main types of glacial erosion - plucking, abrasion and freeze thaw.

Plucking is when melt water from a glacier freezes around lumps of cracked and broken rock. When the ice moves downhill, rock is plucked from the back wall. Abrasion is when rock frozen to the base and the back of the glacier scrapes the bed rock. Freeze-thaw is when melt water or rain gets into cracks in the bed rock, usually the back wall. At night the water freezes, expands and causes the crack to get larger. Eventually the rock will break away.