There are three types of glacial deposition
- Moraines
- Drumlins (boulder clay or till)
- Erratics
Moraine
This is the name given to fragments of rock transported by the glacier and deposited when it melts
- Terminal Moraine:is deposited by the glacier at the snout as it retreats
- Medial Moraine: is material carried in the middle of the glacier
- Lateral Moraine: is the material that has fallen onto the side of a glacier and carried along by it.
Erratics
- These are large boulders or rocks which have been carried by a glacier and deposited in area where it does not belong
- For example it would mean a large boulder of limestone being deposited in an area where the bedrock is made of granite!
Drumlins
- These are made up of a mixture of angular rock fragments and clay (formed by the pressure of ice grinding down the rock over time)
- When the glacier is moving it deposits this clay and rock mixture from the underneath of the glacier.
- As the glacier moves over the boulder clay it shapes them into an egg shape with a high rounded back and narrow tail.
