Glaciated landscapes

physical factors (landscapes)

corrie

Snow gathers in mountain hollows - especially north facing hollows - it builds up and compacts to ice.

As the ice moves downhill it sticks to the back wall and plucks rock from the surface, steepening them.

Freeze thaw action also loosens rocks on the back wall.

Ice moving with loose rock acts like sandpaper and deepens the hollow by abrasion.

Ice in a corrie has a rotational movement which means that the front of the corrie is less eroded and a lip forms.

The glacier melts, often leaving a tarn also known as a corrie loch.

pyramidal peak and arete

Two corries form back to back.

As the glaciers erode the back walls of a corrie get closer and closer, forming a ridge.

Continued erosion makes the ridge narrower with steeper edges.

A pyramidal peak is formed where three or more corries and arêtes meet.

Glaciers erode backwards towards each other, carving out the rocks by plucking and abrasion.

Freeze thaw weathers the top of the mountain, creating a sharply-pointed summit.

U-shaped valley

A glacier erodes a valley through the processes of plucking and abrasion to widen, steepen, deepen and smooth V-shaped river valleys into a U-shape.

Glacier erosion turns V-shaped valleys U-shaped, with a flat floor and steep sides.

A glacier erodes a valley through the processes of plucking and abrasion to widen, steepen, deepen and smooth V-shaped river valleys into a U-shape.

Glacier erosion turns V-shaped valleys U-shaped, with a flat floor and steep sides.

After glaciation, a misfit stream/river or ribbon lake can sometimes occupy the floor of the U-shaped valley.