glacial erosion and landscapes

Question 1

corries

Answer 1

enlarged, often deep hollow on a mountain side
-steep cliff like back wall often with large pile of scree at base
-raised rock lip at front of hollow which acts as a dam to trap water = tarn
-periglacial processes (nivation) increase size - as climatte cools, snow turns to ice in hollow = corrie glacier
- accumulation at top of mass and rotational sliding = abrasion
- climate warrms = temperate processes (frost, water action) modify shape of corrie to create tarn

Question 2

arete

Answer 2

when two neighbouring glaciers cut back into mountainside - narrow, dknife edge ridge forms between two corries

Question 3

pyramidal peak

Answer 3

where 3 or more corries erode back to back, the ridge becomes isolated peak e.g. matterhorn

Question 4

glacial troughs/ U-shapes valleys

Answer 4

-steep sided, mainly flat bottomed and deep (often several hundred metres deep)
-mainl straight due to power and inflexibility of glaciers
- abrasion through basal slip
- can contain deep narrow lakes (ribbon lakes) - result of localised overdeepening due to enhanced erosion from weaker bedrock allowing vertical erosion, merging of tributatry glacier makes greater erosion on valley floor due to increased ice mass, and narrowing

Question 5

hanging valleys

Answer 5

a smaller glacier in trbiutary valley doesn’t have same mass as larger glacier, so it wont be able to erode down as far as large glacier
-when ice melts, smaller valley left hanging above main valley

Question 6

truncated spurs

Answer 6

-when a valey is occupied by ice, the rigi more powerful glacier cits off or truncates the tips of rocky spurs as it moves downhill, leaving steep cliffs (truncated spurs)
- abrasion