Features produced by glacial erosion
The left hand column in the table is a list of features produced by glacial erosion; the second column describes these features; and the
third summarises their formation. At present neither the descriptive nor the formation points match the features.
Feature
Cirque/ Corrie
Description
Pointed peak
Formation
Englacial or subglacial debris dragged over exposed rock
Arete
Tributary glacier left high above the main valley
Extending or compressing flow overdeepens parts of valley
floor
Pyramidal peak
Stepped long profile in a glacial trough
Resistant rock remains after ice abrasion on the ice-directionfacing side and plucking on lee
Glacial trough
Ice-smoothed rocks with steeper side facing
down-valley
Frost shattering, abrasion, plucking and rotational ice
movement
Hanging Valley
Steep-sided. U-shaped valley
Three or more cirques cut backwards
Truncated spur
Small, deep, circular lake
Two cirques cut back towards each other
Rock steps
Overdeepening by abrasion by sub glacial debris moving in a
rotational movement; fills with water after deglaciation
Ribbon lake
An amphitheatre-shaped depression in a
mountain side, with a steep back wall and a
rock lip
Steep, cliff-like valley sides
Tarn
Narrow, knife-edged ridge
Widened and deepened by valley glacier
Roche moutonnee
Rocks scarred with thin parallel scratches
Valley glaciers have removed the ends of interlocking spurs by
abrasion
Striations
Long, narrow lake in a glacial trough
Ice in main valley eroded more rapidly than ice in the tributary
valleys often producing a waterfall
Formed by extending and compressing flow in main valley or
where two glaciers meet
Glacial Erosion Features
Feature
Cirque/ Corrie
Arete
Pyramidal peak
Glacial trough
Hanging Valley
Truncated spur
Rock steps
Ribbon lake
Tarn
Roche moutonnee
Striations
Description
Formation