Moraines are lines or a series of mounds of material, mainly running across glacial valleys. The main type is the terminal and end moraine which is found at the snout of the glacier. Terminal moraines show the following features:
- they consist of a ridge of material streching across a glacial valley.
- they are elongated at right angles to the direction of the ice advance.
- they are often steep sided particulary the ice contact side, and reach heights of 50-60km.
- they are often cresent shaped, moulded to the form of the snout.
- they are formed from unsorted ablation material.
As the glacier retreats, it is possible for a series of moraines to be formed along the valley, marking points where the retreat halted for some time. These are known as recessional moraines.
If the climate cools for sometime, leading to a glacial advance, a prevoiusly deposited moraine may be shunted up into a mould known as push moraine. Such features are recognised by the orientation of individual pieces of rock which may have been pushed upwards from their original position.
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