Formation of a U-shaped valley

Question 1

stage one

snow falls…

Answer 1

North facing slopes are more shaded so snow lies longer here with the accumulated snow compressing into ice

Question 2

stage one

gravity…

Answer 2

When glaciers move downhill due to their weight and gravity they move through an existing ‘v’ shaped valley

Question 3

stage two

plucking

Answer 3

as the glacier moves through the valley plucking occurs

this is when the rocks are removed from the valley floor and sides through freezing and refreezing the rocks, which then are ripped away by the glacier

Question 4

stage two

abrasion

Answer 4

Then abrasion occurs this is when the angular rock embedded in the glacier grinds the bedrock wearing it away which makes it deeper

Question 5

stage two

frost shattering

Answer 5

The frost shattering occurs this is when water freezes and refreshes in cracks of the rocks expanding and contractions weakening it eventually causing it to explode

this causes the valley to be widened, straightened and deepened

Question 6

stage two

interlocking spurs

Answer 6

Interlocking spurs may be cut off by the glacier leading to truncated spurs and deep valley sides

Question 7

stage three

A misfit stream and ribbon lake

Answer 7

A misfit stream may be found

a ribbon lake is formed when the glacier meets weaker bedrock and erodes it more deeply

The glaciers meltwater then fills the eroded land to make a ribbon lake eg Loch Avon in the Cairngorms