Glacier stuff Flashcards
Abrasion
erosion caused by rocks and boulders in the base of the glacier acting like a giant file scratching and scarping the rocks below
Arete
A sharp, knife-like ridge formed between two corries cutting back by processes of erosion and freeze-thaw
Bulldozing
Ice pushes material of all shapes and sizes as it moves slowly forward
Conservation
Managing the environment in order to preserve, protect or restore it.
Corrie
(Cirque) Armchair-shaped hollow in the mountain side formed by glacial erosion, rotational slip and freeze-thaw weathering. This is where the valley glacier begins. When the ice melts,it can leave a small circular lake called a tarn.
Drumlin
A hill made of glacial till deposited by a moving glacier, usually elongated or oval in shape, with the longer axis parallel to the former direction of ice.
Erratics
Rocks which have been transported and deposited by a glacier some distance from their source region.
Freeze thaw weathering
also called frost shattering. It occurs in cold climates when temperatures are often around freezing point and where exposed rocks contain many cracks. Water enters the cracks during the warmer times day and freezes during the colder night. As the water turns into ice it expands and exerts pressure on the surrounding rock,causing pieces to break off
Glacial trough
A river widened and deepened by the erosive action of glaciers; it becomes ‘U’- shaped instead of the normal ‘V’shape of a river valley
Hanging Valley
A tributary valley to the main glacier, too cold and high up for ice to be able to easily move. It therefore was not eroded as much as the normal main valley, and today is often the site for a waterfall crashing several hundreds of metres to the main valley floor.
Land use conflicts
Disagreements which arise when different users of the land do not agree on how it should be used
Moraine
Frost-shattered rock debris and material eroded from the valley floor and sides, transported and deposited by glaciers.
Outwash
Material. chiefly sand or gravel, deposited by meltwater streams in front of, and underneath, a glacier. The material is sorted and rounded by water action
Plucking
A type of erosion where melt water in the glacier freezes onto rocks, and as the ice moves forward it plucks or pulls out large pieces along the rock joints
Pyramidal peak
Where several corries cut back to meet a central point , the mountain takes the form of a steep pyramid.