Competitive Exams: Mountains

Anything above, 600 m (2000 ft) can be regarded as amount mountain. Hill is smaller than mountain but no specific definition for absolute elevation. A mountain may have several forms: Mountain ridge: It is a system of long, narrow and high hills. Generally, the slope of one side of a ridge is steep while the other side is of moderate slope but a ridge may also have symmetrical slopes on both the sides.

Mountain range: It is a system of mountains and hills having several ridges, peaks, summits and valleys. Mountain chain: It consists of several parallel long and narrow mountains of different periods.

Mountain system: It consists of different mountain ranges of the same period. Different mountain ranges are separated by valleys.

Mountain group: It consists of several unsystematic patterns of different mountain systems.

Cordillera: It is a community of mountains having different ridges, ranges, mountain chains and mountain systems. The mountainous region of the western part of North America is the best example of a Cordillera.

Classification of Mountains

  1. On the basis of HEIGHT:

    1. Low mountains: Height ranges between 700 − 1000m

    2. Rough mountains: Height-1000m − 1500m

    3. Rugged mountains: Height-1500 − 2000m

    4. High mountains: Height above 2000m.

  2. On the basis of Location

    1. Continental mountains:

      1. Coastal mountains: Examples are-Appalachians Rockies, Alpine mountain chains, Western and Eastern Ghats of India, etc.

      2. Inland mountains: Examples are-Ural mountains (Russia), Vosges and Black forest block mountains (Europe)

        1. Block mountains: These are originated by tensile forces leading to the formation of rift valleys. They are also called as horst mountains.

        2. Dome mountains: These are originated by magmatic intrusions and upwarping of the crustal surface. Examples are: Normal domes, lava domes, batholithic domes, laccolithic domes, salt domes.

        3. Mountains of Accumulations: These are formed due to accumulation of volcanic materials. Different types of volcanic cones (e. g. cinder cones, composite cones, basic lava cones, etc.) come under this category.

    2. Circum-erosional or Relict mountains: Examples are-Vindhyachal ranges, Aravallis, Satpura, Eastern ghats, Western ghats, etc (all from India).

  3. On the basis of Period Of Origin:

    1. Pre-Cambrian mountains: Examples are-Laurentian mountains, Algoman mountains, Kilarnean mountains, etc (North America). mountains of Feno-Scandia, Northwest highlands and Anglessey, etc (Europe).

    2. Caledonian mountains: These are the mountains formed during Silurian and Devonian periods. Examples are-Taonic mountains of the Appalachian system, mountains of Scotland, Ireland and Scandinavia (Europe), Brazi-lides of South America, Aravallis, Mahadeo, Satpura, etc. Of India.

    3. Hercynian mountains: These are the mountains formed during Permsari and Permocarboniferous periods. Examples are-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, Frankenn Hartz mountain, Donbas coalfield (all in Europe), Varsican mountains of Asia include Altai, Sayan, Baikal Arcs, Tien Shan, Khingan, Tarim basin, Nanshan Alai and Trans Alai mountains of Amur basin. North American Variscan mountains include Applachians; South American Variscan mountains are Austrian and Saalia folds of San Juan and Mendoza, mountains of Puna are of Atacama, Gondwanides of Argentina

    4. Alpine mountains: These are the mountains formed during tertiary period. Examples are-Rockies (North America), Andes (South America), Alpine mountain systems of Europe (mainly Carpathians, Pyrenees, Dinaric, Alps, etc.), Atlas mountains of north-west Africa; Himalayas and mountains coming out of Pamir Knot of Asia (Taurus, Pauntic, Zagros, Elburz, Kunlun, etc.). Atlas mountains of north-west of Africa.

Block Mountains

  1. Motored by endogenetic forces coming from within the earth. Block mountains are basically of two types, e. g.

    1. tilled block mountains having one steep side represented by fault scarp and one gentle side, and

    2. lifted block mountains represent real horst and are characterized by flattened summit of tabular shape and very steep side slopes represented by two boundary fault scarps. Block mountains are also called as horst mountains.

  2. Block mountains are found in all the continents, for example: Young block mountains around Albert Warner

  3. P Klamath lakes in the Steens mountain district of South Oregon, Wasatch range in Utah province, etc. In USA. Vosges and Black forest mountains bordering the faulted Rhine rift valley in Europe. Salt range of Pakistan, etc. Sierra Navada mountain of California (USA) is considered to be the most extensive block mountain of the world and movement of side blocks.

Discussions & Questions

  • 1) Is it due to the revolution of earth on its tilted axis that causes variation of the length of daytime and nighttime form season to season? 2)Reason for jet flying in lower stratosphere? ( - on ))

    1 Answer

    Please refer the series of free videos on geography and geomorphology which will help you answer your doubts-https://www.youtube.com/playlist?list=PLW9kB_HKs3_NtPsdNsuhPVl__bqXlMwiI, more videos will be added shortly.

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