Movement
- Ablation
- wastage of the glacier through sublimation, ice melting and iceberg calving.
- Ablation zone
- Area of a glacier in which the annual loss of ice through ablation exceeds the annual gain from precipitation.
- Arête
- an acute ridge of rock where two cirques abut.
- Bergshrund
- crevasse formed near the head of a glacier, where the mass of ice has rotated, sheared and torn itself apart in the manner of a geological fault.
- Cirque, corrie or cwm
- bowl shaped depression excavated by the source of a glacier.
- Creep
- adjustment to stress at a molecular level.
- Flow
- movement (of ice) in a constant direction.
- Fracture
- brittle failure (breaking of ice) under the stress raised when movement is too rapid to be accommodated by creep. It happens for example, as the central part of a glacier moves faster than the edges.
- Horn
- spire of rock, also known as a pyramidal peak, formed by the headward erosion of three or more cirques around a single mountain. It is an extreme case of an arête.
- Plucking/Quarrying
- where the adhesion of the ice to the rock is stronger than the cohesion of the rock, part of the rock leaves with the flowing ice.
- Tarn
- a post-glacial lake in a cirque.
- Tunnel valley
- The tunnel is that formed by hydraulic erosion of ice and rock below an ice sheet margin. The tunnel valley is what remains of it in the underlying rock when the ice sheet has melted.
Read more about this topic: Glaciology
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