Mountains
*Mainly there are three types of landforms–Mountains, Plateaus, and Plains.
* The height of mountains is over 600 metres and these have conical peaks. On the basis of origin there are four types of mountains; Block Mountains, Residual Mountains, Accumulated Mountains and Fold Mountains.
Block Mountains
*They are formed when great block of earth’s crust may be raised or lowered due to tectonic activities.
*When the earth’s crust cracks due to tension or compression, faulting takes place. Examples of Block Mountain: Narmada, Tapti and Damodar valley in India, the Vosges in France, Salt Range in Pakistan and Block forest (Rhine valley) in Germany.
Volcanic Mountains
They are formed due to the accumulation of volcanic material.
It is also called as Mountains of Accumulation.
Examples: Mt. Fuji (Japan), Cotopaxi in Andes, Vesuvius and Etna in Italy, Mt. Mayon (Philippines), Kilimanjaro in Africa, Mt. Merapi in Sumatra etc.
Residual or Dissected Mountains
They are formed as a result of erosion of plateaus and high plains by various agents of erosion.
Examples: Catskill mountains of New York. Nilgiri, Parasnath, Girnar and Rajmahal, Vindhyachal ranges, Aravallis, Satpura, Eastern and Western Ghats of India.
Accumulated Mountains
These are formed due to accumulation of sand, soil, rocks, lava, etc. on the Earth’s crust, e.g., sand dunes.
Fold Mountains
It is formed due to the compressive forces generated by endogenetic forces (earthquake, landslide, etc.). Examples of fold mountains are Himalayas, Alps, Andes, Rockies, Atlas, etc.
(a) Young/New Fold Mountains: It came into existence after the continental drift. Himalayas are regarded as the youngest mountains in the world.
(b) Old Mountains: They belong to pre-drift era, then subject to denudation and uplift, e.g., Aravallis (India), etc.