Once glacial ice has melted, a variety of rocks are laid down that have been carried down by the glacier. Piles of this material is named Moraines. They are usually seen as lines, or a series of mounds running across glacial valleys.
There are many types of moraines (See figure 1) ; the main types are terminal or end moraine which are found at the snout of the glacier.
Figure 1: Diagram illustrating the different types of moraines. (Source: Reference)
Terminal Moraines:
- Consist of a material ridge stretching across a glacial valley
- they are elongated at right angles to the direction of the ice advance
- often steep sided and can reach heights of 50-60m
- often crescent shaped, moulded to the form of the snout
- formed from unsorted ablation material when the ice melts and the carried material has been deposited (Therefore they contain a variety of material)
As a glacier retreats, a series of moraines may be formed along the glacial valley, marking points where the retreat may have paused. (Recessional Moraines)
When the climate cools down, a glacial advance will occur and the previously deposited moraine may be shunted up into a mound known as a push moraine.
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