In this article we will discuss about the classification of mountains on the basis of height, location, mode of origin and period of origin.
On the Basis of Height:
(i) Low mountains; height ranges between 700 to 1,000 m.
(ii) Rough mountains; height-1000 m to 1,500 m
(iii) Rugged mountains; height-1,500 to 2,000 m.
(iv) High mountains; height above 2,000 m.
On the Basis of Location:
(i) Continental mountains:
(a) Coastal mountains, examples:
Applachians, Rockies, Alpine mountain chains, Western and Eastern Ghats of India etc.
(b) Inland mountains:
examples, Ural mountains (Russia), Vosges and Black Forest block mountains (Europe), Himalayas, Aravallis, Satpura, Maikal, Kaimurs etc. (India), Kunlun, Tienshan, Altai etc. (Asia) etc.
(ii) Oceanic mountains:
Most of the oceanic mountains are below the water surface (below sea level). Oceanic mountains are located on continental shelves and ocean floors. Some oceanic mountains are also well above sea level. If the height of the mountains is considered from the oceanic floor and not from the sea level, many of the oceanic mountains will become much higher than the Mount Everest.
For example, Mauna Kea volcanic mountain of Hawaii Island is 4200 m high from the sea level but if its height is considered from the sea bottom, its height becomes 9140 m which is higher than the highest mountain, Mount Everest (8848m AMSL) of the continent.
Similarly, the Antilean Mountain system is 3000 m above sea level but it is also 5400 m below sea level, and thus its total height from the oceanic floor becomes 8400 m. Most of the oceanic mountains are volcanic mountains.
On the Basis of Mode of Origin:
(1) Original or tectonic mountains are caused due to tectonic forces e.g. compressive and tensile forces motored by endogenetic forces coming from deep within the earth. These mountains are further divided into 4 types on the basis of orogenetic forces responsible for the origin of a particular type of mountain.
(i) Folded mountains are further divided into 3 sub-types on the basis of their area.
These are originated by compressive forces:
(A) Young folded mountains.
(B) Mature folded mountains.
(C) Old folded mountains.
(ii) Block mountains are originated by tensile forces leading to the formation of rift valleys. They are also called as horst mountains.
(iii) Dome mountains are originated by magmatic intrusions and up-warping of the crustal surface. Examples, normal domes, lava domes, batholithic domes, laccolithic domes, salt domes etc.
(iv) Mountains of accumulations are formed due to accumulation of volcanic materials. Thus, these are also called as volcanic mountains. Different types of volcanic cones (e.g., cinder cones, composite cones, acid lava cones, basic lava cones etc.) come under this category.
(2) Circum-erosional or relict mountains: examples, Vindhyachal ranges, Aravallis, Satpura, Eastern Ghats, Western Ghats etc. (all from India).
On the Basis of Period of Origin:
(1) Pre-cambrian Mountains:
Examples, Laurentian mountains, Algoman mountains,. Kilarnean mountains etc. (North America), mountains of Feno- Scandia, North-West Highlands and Anglesey etc. (Europe).
(2) Caledonian Mountains:
Mountains formed during Silurian and Devonian periods, examples: Taconic mountains of the Applachian system, mountains of Scotland, Ireland and Scandinavia (Europe), Brazilides of South America, Aravallis, Mahadeo, Satpura etc. of India.
(3) Hercynian Mountains:
Hercynian mountains formed during Permian and Permocarboniferous periods, examples: mountains of Iberian peninsula, Ireland, Spanish Messeta, Brittany of France, South Wales, Cornwall, Mendips, Paris basin, Belgian coalfields, Rhine Mass, Bohemian plateau, Vosges and Black Forest, plateau region of central France, Thuringenwald, Franken wald, Hartz mountain, Donbas coal field (all in Europe); Variscan mountains of Asia include Altai, Sayan, Baikal Arcs, Tien Shan, Khingan, mountains of Dzungarian basin, Tarim basin, Nanshan, Alai and Trans Alai mountains of Amur basin, Mongolia and Gobi etc.; Australian Variscan mountains include the scattered hills in the Eastern Cordillera, New England of New Southwales; North American Variscan mountains include Applachians; South American Variscan mountains are Austrian and Saalian folds of San Juan and Mendoza, mountains of Puna area of Atacama, Gondwanides of Argentina etc.
(4) Alpine mountains:
mountains formed during Tertiary period, examples, Rockies (North America), Andes (South America), Alpine mountain systems of Europe (main Alps, Carpathians, Pyrenees, Balkans, Caucasus, Cantabrians, Appenines, Dinaric Alps etc.), Atlas mountains of north-west Africa; Himalayas and mountains coming out of Pamir Knot of Asia (Taurus, Pauntic, Zagros, Elburg, Kunlum etc.).