Corrie Formation
Rotational sliding and friction
Lochan and example
Erosion
Conditions
Freeze-thaw and bergschrund
- Plucking is when ice freezes on to bedrock
- pulling loose rock away from the landscape, making it steeper.
- Abrasion is when the angular rock embeded in the ice
- grinds the landscape making it deepers
- Snow accumulates in north facing mountain hollows
- when more snow falls in winter than melts in the summer.
- Freeze thaw weathering on the backwall supplies further abrasion material helping to further deepen the corrie
- The scree falls into the bergschrund which is large crevasse separating moving ice from ice still attached to the back wall
- Rotational sliding deepens the hollow floor as gravity causes the ice to move and melt water from the glacier helping it to slide.
- The lip traps water as it melts, leaving a lochan
- e.g corrie cas, carirngorms.
- freeze thaw weathering when water in cracks in the rock freezes, expands and contracts weakening the rock until fragments break off.