Glacial Erosional Landforms Flashcards
What is a cirque?
Armchair shaped hollow in a mountainside with a steep backwall and a rock lip.
How is a cirque formed?
A large rounded hollow high on a mountainside is eroded and deepened by plucking (at the backwall) and abrasion due to the rotational ice movement
What is an example of a cirque?
Cwm Idwal, Snowdonia
What is an arete?
A narrow, knife-edged ridge between two cirques
How is an arete formed?
Plucking and abrasion on the backwall of each cirque mean they erode backwards towards one another
What is an example of an arete?
Striding Edge, Lake District
What is a pyramidal peak?
A pointed mountain with three or more cirques
How is a pyramidal peak formed?
The erosional processes (mainly plucking) such as plucking within multiple nearby cirques mean they erode backwards towards each other to create a sharp pointed mountain
What is an example of a pyramidal peak?
Mount Everest, Himalayas
What is a U-shaped valley?
A valley with steep sides and a wide, flat floor
How is a U-shaped valley formed?
A V-shaped river valley is widened and deepened by plucking/abrasion by a glacier which goes through the landscape rather than around it
What is an example of a U-shaped valley?
Nant Ffrancon Valley, Snowdonia
What is a truncated spur?
Very steep, almost vertical valley sides where interlocking spurs of a river valley once were
How is a truncated spur formed?
Valley glaciers remove the ends of interlocking spurs through plucking and abrasion as they move down the valley
What is an example of a truncated spur?
Truncated spurs in the Nant Ffrancon Valley