IB Geography Glacial Landforms

Erosion: Striations

Long scratches created where moraine scraped against resistant rock

Erosion: Cirque/Corrie/Cwm

Steep sided, half-open hollow formed at the head of a glacier

Erosion: Tarn/Lochan/Corrie Lake

Lake formed by meltwater and/or precipitation in a cwm

Erosion: Horn/Pyramidal Peak

Forms where multiple cwms carve out the mountainside

Erosion: Truncated Spurs

Formed where a glacier cuts off interlocking spurs formed by a river

Erosion: Nunataks

Rocky island surrounded by glacial ice

Erosion: Hanging Valley

Formed where the U-shaped valleys of tributary glaciers meet the main U-shaped valley

Erosion: Arête

Spine between two cwms or glacial valleys

Erosion: Fjord

U-shaped valley flooded by rising sea levels

Erosion: Ribbon/Finger Lake

Lake formed in the depression left by overdeepening by the base of a glacier

Erosion: Glacial Trough

U-shaped valley formed where a glacier has passed

Erosion: Roche Mountonée

Rocks, one side smoothed by abrasion and the other steep and rough from plucking

Deposition: Till

Boulder clay, unconsolidated, variety of particle sizes

Deposition: Erratics

Boulders deposited from the glacier with foreign geology

Deposition: Moraine

Any rock carried by the glacier, lateral, medial, ground, terminal

Deposition: Drumlins

Smooth, elongated mounds of till, steep on one side and gentle on the other, often found in groups

Deposition: Kettle Holes/Lakes

Form from detached blocks of ice, melt and leave behind a depression which often fills with water

Deposition: Glacial Flour

Suspended load of rock dust in water

Deposition: Outwash

Flat areas of meltwater below the snout of glaciers, made from till, eskers, erratics, drumlins all found on this plain

Deposition: Eskers

Long, narrow ridges of sand+gravel, formed by deposits of sub-glacial meltwater streams