Corries and Glacial Valleys Flashcards
What are the features of a corrie?
Armchair shape, steep backwall, shattered rock, deep tarn lake, rock lip and a waterfall
What is the first stage in the formation of a corrie?
When snow builds up in a hollow high up on the north face of mountain sides over a year.
What is the second stage in the formation of a corrie?
The ice moves under its own weight in a circular way called rotational movement
What is the third stage in the formation of a corrie?
Rocks that have fallen into the glacier ice scrape away the glacier floor by abrasion and a deep bowl shape is formed.
What is the fourth stage in the formation of a corrie?
The mountain top is weathered by freeze-thaw. Persistent freezing and melting breaks the sediment into the ice.
What is the fifth stage in the formation of a corrie?
It gets eroded due to plucking by the water freezing and then pulling off rock. It develops a vertical shaped, jagged appearance.
What is the sixth stage in the formation of a corrie?
Because the ice is thinner at the front of the corrie, there is less erosion and a rock lip is formed. Moraines are also deposited here.
What is the seventh stage in the formation of the corrie?
A small corrie full with ice, flows out onto the main valley glacier
What is the final stage in the formation of a corrie?
When the ice melts a small but very deep lake usually formed in the deep bowl called a tarn
What are the features of a glaciated valley?
It is very wide and relatively straight, gently curved sides, small stream, grassed surfaces and a glacial ‘trough’
What are the features of a river valley?
It is narrow, steep, has interlocking spurs of hard land and rock scree
What shape is a glaciated valley?
‘U’ shaped
What shape is a river valley?
V-shaped
- What happens before glaciation?
The river carves out a V-shaped valley because it erodes out the base
- What happens during glaciation?
The ice fills the whole valley
