Image Source May 19, 2021 20:49 IST · 6 min read
A plateau is an elevated area with a more or less levelled land on its top. It has a large area on its top and a steep slope on its sides.
The plateaus cover about 18% of the earth?s land surface and also called as high plains or tablelands.
Valleys form when river water cuts through the plateau. The Columbia Plateau, between the Cascade and Rocky mountains in the northwestern United States, is cut through by the Columbia River.
Plateau are rich in mineral deposits, Iron ore and coal often are found in their outliers.
Classification of the Plateaus
Broadly plateaus are of two types: Dissected Plateaus and Volcanic Plateaus.1) Dissected Plateaus
Dissected Plateaus are formed as a result of upward movement in the earth's crust caused by slow collision of tectonic plates. The Colorado Plateau, in the western United States, has been rising about .03 centimeter (.01 inch) a year for more than 10 million years.2) Volcanic Plateaus
Volcanic Plateaus are ormed by numerous small volcanic eruptions that slowly builds up over the time, forming a plateau from the resulting lava flows. For example: Mount Tongariro, Mount Ngauruhoe, Mount Ruapehu etc.On the basis of their geographical location and structure of rocks, the plateaus can be classified as:
1) Intermontane Plateaus
The plateaus which are bordering the fold mountain range or are partly or fully enclosed within them are called Intermontane Plateaus.Intermontane plateaus are the highest in the world.
The Plateau of Tibet is an example of the intermontane plateau which is surrounded by the fold mountains like the Himalayas, the Karakoram, the Kunlun and the Tien Shah.
2) Piedmont plateaus
Piedmont plateaus are formed due to various agents of erosion reducing the level of mountain.They are also called as Plateaus of denudation as the areas once were high to the level of mountains, have now been reduced to the foot level of the mountain by various agents of erosion.
The Malwa Plateau is an example of piedmont plateau.
3) Continental plateaus
Continental plateaus are formed either by an extensive continental upliftment or by the spread of horizontal basic lava (less viscous) sheets completely covering the original topography.This kind of plateaus shows an abrupt elevation in contrast to the nearby lowland or sea (i.e. more steepness on sides).
Plateau of Maharashtra is an example of the continental plateau.
4) Volcanic plateaus
There are two main types of Volcanic plateaus: lava plateaus and pyroclastic plateaus.Lava plateaus are formed by highly fluid basaltic lava during numerous successive eruptions through numerous vents without violent explosions.
Pyroclastic volcanic plateaus are produced by massive pyroclastic flows and they are underlain by pyroclastic rocks.
Major Plateaus in the world
Here is a list of major Plateaus of the World with their location and characteristics:1) Tibetan Plateau
Tibetan Plateau also called "roof of the world" is the highest and largest plateau in the world. It is formed due to collision of the Indo-Australian and Eurasian tectonic plates.It covers most of the autonomous Tibetan Region, Qinghai Province of Western China, and a part of Ladakh in India.
It is surrounded by mountains to the south by the Himalayan Range, to the northeast by the Kunlun Range, and to the west by the Karakoram Range.
2) Laurentian Plateau (Canada)
The Laurentian Plateau lies in the eastern part of Canada, it is a part of Canadian Shield.It is made of Pre-Cambrian rocks and contains reserves of various types of metallic minerals. Fine quality of iron-ore is found here.
3) Columbia-Snake Plateau
Columbia-Snake Plateau is formed as a result of volcanic eruptions with a consequent coating of basalt lava (Flood Basalt Plateau).It is bordered by the Cascade Range and Rocky Mountains and is divided by the Columbia River.
4) Colorado Plateau
Colorado Plateau lies in western part of U.S. and is divided by the Colorado River and the Grand Canyon.It is bounded by the Rocky Mountains from north and east, in the west by the Great Basin, and from the south by the Sonoran Desert.
This plateau is an example of intermontane plateau and is the largest plateau in America.
It is also known for the groundwater which is under positive pressure and causes the emergence of springs called Artesian wells.
Mesas and buttes are found here at many places.
5) Deccan Plateau
Deccan Plateau is bordered by the Western Ghats and the Eastern Ghats and includes Deccan Traps (largest volcanic feature on Earth.)It is largest plateau in India and is made of multiple basalt layers or lava flows, the Deccan Traps are known for containing some unique fossils.
The Deccan is rich in minerals, primary mineral ores found in this region are mica and iron ore in the Chotanagpur region, and diamonds, gold and other metals in the Golconda region.
6) Kimberley Plateau
Kimberley Plateau is made of volcanic eruption and lies in the northern part of Australia.Many minerals like iron, gold, lead, zinc, silver and diamond are found here.
7) Katanga Plateau
Katanga Plateau lies in Congo and is famous for copper and uranium deposits.Other minerals like Cobalt, Uranium, Zinc, Silver, Gold and Tin are also mined here.
8) Mascarene Plateau
Mascarene Plateau is formed in the ocean and extends between the Seychelles and Mauritius Islands.It is the second largest undersea plateau in the Indian Ocean after the Kerguelen Plateau.
It is made of granite, and is a fragment of the ancient supercontinent of Gondwana.
9) Mexican Plateau
Mexican Plateau, also called as Mineral Store is home to world's biggest silver mine "Chihuahua".10) Patagonian Plateau
Patagonian Plateau is a Piedmont plateau (Arid Landforms) lying in southern part of Argentina.It is semi-arid scrub, rain shadow desert plateau and an important region for sheep rearing.
11) Altiplano Plateau (Bolivian Plateau)
Bolivian Plateau is an series of intermontane plateau, located between two ranges of Andes Mountain.It is a major area of Tin reserves.
12) Massif Central
Massif Central plateau lies in the central France and is famous for Grapes cultivation.13) Anatolian Plateau
Anatolian Plateau is an intermontane plateau lying between Pontiac and Taurus Mountain ranges.It is also known as Asia Minor, most of Turkey lies on this plateau.
Tigris - Euphrates Rivers flow through this plateau, precious wool producing Angora goats are found here.
14) Potwar Plateau
Potwar Plateau is situated in northern plateau (Punjab) region of Pakistan.15) Bavarian Plateau (Alpine Foreland)
Bavarian Plateau, located in Germany, formed under the influence of the ice ages and has a rich variety of landforms.16) Spanish Plateau (Iberian Plateau)
Spanish Plateau is formed by the volcanic eruption and lava, one of the best quality iron is found in this region.17) Loess Plateau (Huangtu Plateau)
Loess Plateau is located in China and is famous for highly erodible soil on the Earth.18) Ahaggar Plateau
Ahaggar Plateau, also called as 'Hoggar' is located in Algeria.The region is composed of black volcanic (basalt).