Fold Mountains
Fold mountains are landforms that occur at destructive plate margins.
Formation of fold mountains :
1. First, thick sediment layers form in huge depressions under the sea. These are called geosynclines.
2. Over millions of years the sediments are compressed into rock.
3. The sedimentary rocks are forced into folds as the plates move. This causes fold mountains.
A Fold Mountain Case Study :
Alps
Himalayas
Ocean Trenches
These are formed in the subduction zone of a destructive plate margin. One wall of the trench is the subducting oceanic crust. The other wall is the edge of the continental crust.
Ocean trenches are little use to humans as they are very deep; too deep for any human to be able to reach the ocean floor to drill for oil.
