When are mountains formed?

Mountains can be formed in three different ways. Volcanoes form mountains when lava from deep inside the Earth cools and hardens on the surface.

Other mountains are formed when two plates move towards each other under pressure or where an oceanic plate is pushed under a continental crust. The pressure causes the ground near the joining plate margins to fault and fold. The ground is forced upwards to form mountains. The Rockies, Alps, Andes, Urals and Himalayas were all formed in this way.

Finally the Earth’s crust can fracture and create faults which mean that large blocks of land can be moved upwards or downwards. Faults in the rocks normally occur when there is a lot of pressure on the rocks. Mountain building is a slow process and happens over centuries.

Fact File:

Rock slides are common where forests have been destroyed on mountainsides. There are no longer any tree roots to stabilize the loose material.


Picture Credit : Google