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Plate Tectonics

A tectonic plate (also called lithospheric plate) is a massive, irregularly-shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. 

The theory of plate tectonics proposes that the earth’s lithosphere is divided into seven major and some minor plates:

The major plates are: 

  • Antarctica and the surrounding oceanic plate
  • North American (with western Atlantic floor separated from the South American plate along the Caribbean islands) plate
  • South American (with western Atlantic floor separated from the North American plate along the Caribbean islands) plate
  • Pacific plate
  • India-Australia-New Zealand plate
  • Africa with the eastern Atlantic floor plate; and 
  • Eurasia and the adjacent oceanic plate

Major plates

  • Antarctica and some other surrounding oceanic plates are considered the major plates.
  • Pacific plate
  • India- Australia – New Zealand plate
  • Africa with the eastern Atlantic Floorplate
  • Eurasia and the abutting oceanic plate
  • North American plate. It is with the western Atlantic floor separated from the South American Plate Along with the Caribbean islands
  • South American plate with western Atlantic floor separated from the North American plate along the Caribbean islands

Minor plate

  • Cocos Plate: Present in between Central America and Pacific plate
  • Nazca Plate: Present in between South America and the Pacific Plate
  • Arabian Plate: Mostly present in the Saudi Arabian landmass.
  • Philippine Plate: Present in between Asiatic and Pacific plate
  • Caroline Plate: Present in between Philippine and Indian Plate( North of New Guinea)
  • Fuji Plate: Present in the northeast of Australia.

The Indian Plate 

Peninsular India(South India) was included in the Indian Plate. Other than Peninsular India, Australian Continental Portions are incorporated in it.

  • As the subduction zone is along the Himalayas, it forms a boundary in the northern plate. This boundary is in the form of continent-continent convergence
  • Arakan Yoma Mountains of Myanmar widen in the direction of the island on the east side. It enlarges through the Java Trench
  • The eastern boundary is a spreading site present on the east side of Australia. This margin is represented in the form of oceanic ridges in the southwest pacific
  • In the Kirthar Mountain of Pakistan, the western margin lies. It joins the spreading sites present in the red sea rift located in the southeast direction accompanying the Chagos Archipelago
  • Oceanic ridge (divergent boundary) is present in the middle of the Antarctic plate in India. This ridge is present in the west-east direction. It combines a smaller portion of south New Zealand spreading site

Movement of Indian Plate 

  • At the time of Pangaea’s breaking up, India started its journey in the north direction about 200 million years ago
  • About 40 to 50 million years ago, the sudden elevation of the Himalayas have taken place when India collided with Asia
  • Outrush of lava and evolution of Deccan traps happened when the Indian plate moved towards the Eurasian Plate
  • The emergence of the Himalayas took place 40 million years ago

Conclusion

A tectonic plate (also known as a lithospheric plate) is a huge, irregularly shaped slab of solid rock made up of both continental and oceanic lithosphere. Tectonic plates are about 62 miles thick. Oceanic and continental tectonic plates are the two basic kinds of tectonic plates. Oceanic plates are made up of an oceanic crust known as “sima.” Sima is mostly composed of silicon and magnesium (which is where it gets its name). Continental plates are made out of a continental crust known as “sial.” Sial is mostly composed of silicon and aluminium.

  • The lithosphere of the Earth is split into seven major and several minor plates.
  • The primary plates are surrounded by Young Fold Mountain ridges, oceanic trenches, and transform faults.

    These are some examples:
  • The Antarctic plate (as well as the neighbouring oceanic plate)
  • The North American plate (with western Atlantic floor separated from the South American plate along the Caribbean islands)
  • The plate from South America (with western Atlantic floor separated from the North American plate along the Caribbean islands)
  • The plate from the Pacific
  • Plate India-Australia-New Zealand
  • The Africa with the floor plate of the eastern Atlantic
  • Eurasia and its neighbouring oceanic plate

Among the important minor plates are:

  • Between Central America and the Pacific plate is the Cocos plate
  • The Nazca plate is located between South America and the Pacific plate
  • Arabian plate: The majority of Saudi Arabia’s landmass
  • Between the Asiatic and Pacific plates is the Philippine plate
  • Caroline plate: between a Philippine and an Indian plate (North of New Guinea)
  • Fuji plate: Australia’s north-east
  • South-east of the North American Plate is the Juan de Fuca Plate