Landscapes created by Glacial Deposition Flashcards
Why does a glacier deposit material
When a glacier melts it can lose energy.
Any material that is carried can therefore become deposited.
Material that is carried/ deposited by a glacier is called moraine.
Depending on the amount of weathering/ erosion that has taken place on the material this will determine its size.
Small, fine sediment is called rock flour,
slightly larger sediment is called boulder clay or till. Large boulders dumped away from their source are called erratics.
What are the materials left by glacial deposition - Moraine?
Moraine is the materials left by a glacier.
Ground moraine is the layer left under the glacier.
Lateral moraine is found along both edges of the glacier; it is the weathered rock that has fallen from the valley sides. When these melt, ridges are left at the side of the valley.
When two glaciers converge, the lateral moraine joins together in the middle of the glacier to form medial moraine.
Terminal moraine is dropped at the end of the glacier at its snout. This can be used to show the maximum extent that the glacier reached.
What are the materials left by glacial deposition - Drumlin
A low oval mound or small hill, typically one of a group, consisting of compacted boulder clay moulded by past glacial action.
It is often described as a basket of eggs topgraphy e.g. Hellifield in the Yorkshire dales
When a glacier retreats it leaves behind moraine which has a blunt end and a tapered end, the later reflects the direction of the
What are the materials left by glacial deposition - An eratic?
An erratic is a boulder transported and deposited by a glacier having a different composition to the bedrock upon which it is sitting.
Erratics are useful indicators of patterns of former ice flow.
Good to know maps Jamie
Spot the features of glaciation on and OD map
Corrie
Tarn
Arete
Pyramidal peak
Truncated spur etc
