List of tectonic plates

The 15 major plates
Plate tectonics map from NASA

This is a list of tectonic plates on the Earth's surface. Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. The plates are around 100 km (62 mi) thick and consist of two principal types of material: oceanic crust (also called sima from silicon and magnesium) and continental crust (sial from silicon and aluminium). The composition of the two types of crust differs markedly, with mafic basaltic rocks dominating oceanic crust, while continental crust consists principally of lower-density felsic granitic rocks.

Current plates

Geologists generally agree that the following tectonic plates currently exist on the Earth's surface with roughly definable boundaries. Tectonic plates are sometimes subdivided into three fairly arbitrary categories: major (or primary) plates, minor (or secondary) plates, and microplates (or tertiary plates).

Major/main plates

These plates comprise the bulk of the continents and the Pacific Ocean. For purposes of this list, a major plate is any plate with an area greater than 20 million km2.

  • Pacific Plate – An oceanic tectonic plate under the Pacific Ocean – 103,300,000 km2
  • North American Plate – Large tectonic plate including most of North America, Greenland and a bit of Siberia – 75,900,000 km2
  • Eurasian Plate – A tectonic plate which includes most of the continent of Eurasia – 67,800,000 km2
  • African Plate – Tectonic plate underlying Africa west of the East African Rift – 61,300,000 km2
  • Antarctic Plate – A tectonic plate containing the continent of Antarctica and extending outward under the surrounding oceans – 60,900,000 km2
  • Indo-Australian Plate – A major tectonic plate formed by the fusion of the Indian and Australian plates – 58,900,000 km2 often considered two plates:
    • Australian Plate – A major tectonic plate, originally a part of the ancient continent of Gondwana – 47,000,000 km2
    • Indian Plate – A major tectonic plate once part of the supercontinent Gondwana – 11,900,000 km2
  • South American Plate – A major tectonic plate which includes most of South America and a large part of the south Atlantic – 43,600,000 km2

Minor plates

These smaller plates are often not shown on major plate maps, as the majority do not comprise significant land area. For purposes of this list, a minor plate is any plate with an area less than 20 million km2 but greater than 1 million km2.

Microplates

These plates are often grouped with an adjacent major plate on a major plate map. For purposes of this list, a microplate is any plate with an area less than 1 million km2. Some models identify more minor plates within current orogens (events that lead to a large structural deformation of the Earth's lithosphere) like the Apulian, Explorer, Gorda, and Philippine Mobile Belt plates. There may be scientific consensus as to whether such plates should be considered distinct portions of the crust; thus new research could change this list.[1][2][3][4]

  • African Plate
    • Lwandle Plate – A mainly oceanic tectonic microplate off the southeast coast of Africa
    • Madagascar Plate – A tectonic plate formerly part of the supercontinent Gondwana
    • Rovuma Plate – One of three tectonic microplates that contribute to the Nubian Plate and the Somali Plate
    • Victoria Plate
    • Seychelles microcontinent – A microcontinent underlying the Seychelles in the western Indian Ocean
  • Antarctic Plate
  • Australian Plate
    • Capricorn Plate – Proposed minor tectonic plate under the Indian Ocean
    • Futuna Plate – A very small tectonic plate near the south Pacific island of Futuna
    • Kermadec Plate – a long, narrow tectonic plate west of the Kermadec Trench
    • Maoke Plate – A small tectonic plate in western New Guinea
    • Niuafo'ou Plate – Small tectonic plate west of Tonga
    • Tonga Plate – A small southwest Pacific tectonic plate
    • Woodlark Plate – A small tectonic plate located in the eastern half of the island of New Guinea
  • Caribbean Plate
    • Panama Plate – A small tectonic plate sandwiched between the Cocos Plate and Nazca Plate to the south and the Caribbean Plate to the north
    • Gonâve Microplate – Part of the boundary between the North American Plate and the Caribbean Plate
    • South Jamaica Microplate[5]
    • North Hispaniola Microplate[5]
    • Puerto Rico-Virgin Islands Microplate
  • Cocos Plate
    • Rivera Plate – Small tectonic plate off the west coast of Mexico
  • Eurasian Plate
    • Adriatic Plate, also known as Apulian Plate – A small tectonic plate in the Mediterranean
    • Aegean Sea Plate, also known as Hellenic Plate – A small tectonic plate in the eastern Mediterranean Sea
    • Amurian Plate – A minor tectonic plate in eastern Asia
    • Anatolian Plate – A continental tectonic plate comprising most of the Anatolia (Asia Minor) peninsula
    • Banda Sea Plate – A minor tectonic plate underlying the Banda Sea in southeast Asia
    • Iberian Plate – Small tectonic plate now part of the Eurasian plate
    • Iranian Plate – Tectonic plate including Iran and Afghanistan, and parts of Pakistan and Iraq
    • Molucca Sea Plate – A small fully subducted tectonic plate
      • Halmahera Plate – A small tectonic plate in the Molucca Sea
      • Sangihe Plate – A microplate within the Molucca Sea Collision Zone of eastern Indonesia
    • Okinawa Plate – A minor tectonic plate from the northern end of Taiwan to the southern tip of Kyūshū
    • Pelso Plate – A small tectonic unit in the Pannonian Basin in Europe
    • Sunda Plate – A minor tectonic plate including most of Southeast Asia
    • Timor Plate – A microplate in southeast Asia carrying the island of Timor and surrounding islands
    • Tisza Plate – A tectonic microplate, in present-day Europe
    • Yangtze Plate – A small tectonic plate carrying the bulk of southern China
  • Nazca Plate
    • Coiba Plate – A small tectonic plate off the coast south of Panama and northwestern Colombia
    • Malpelo Plate – A small tectonic plate off the coast west of Ecuador and Colombia
  • North American Plate
    • Greenland Plate – A supposed tectonic plate containing the Greenland craton
    • Okhotsk Plate – Minor tectonic plate inclucing the Sea of Okhotsk, the Kamchatka Peninsula, Sakhalin Island and Tōhoku and Hokkaidō in Japan
    • Juan de Fuca Plate – A small tectonic plate in the western North Pacific
    • Explorer Plate – An oceanic tectonic plate beneath the Pacific Ocean off the west coast of Vancouver Island, Canada
    • Gorda Plate – One of the northern remnants of the Farallon Plate
  • Pacific Plate
  • Philippine Sea Plate
  • South American Plate
    • Altiplano Plate
    • Falklands Microplate
    • North Andes Plate – A small tectonic plate in the northern Andes

Ancient continental formations

In the history of Earth many tectonic plates have come into existence and have over the intervening years either accreted onto other plates to form larger plates, rifted into smaller plates, or have been crushed by or subducted under other plates (or have done all three).

Ancient supercontinents

A supercontinent is a landmass consisting of multiple continental cores. The following list includes the supercontinents known or speculated to have existed in the Earth's past:

Ancient plates and cratons

Not all plate boundaries are easily defined, especially for ancient pieces of crust. The following list of ancient cratons, microplates, plates, shields, terranes, and zones no longer exist as separate plates. Cratons are the oldest and most stable parts of the continental lithosphere and shields are the exposed area of a craton(s). Microplates are tiny tectonic plates, terranes are fragments of crustal material formed on one tectonic plate and accreted to crust lying on another plate, and zones are bands of similar rocks on a plate formed by terrane accretion or native rock formation. Terranes may or may not have originated as independent microplates: a terrane may not contain the full thickness of the lithosphere.

African plate

Antarctica plate

Eurasian plate

Indo-Australian plate

Basic geological regions of Australia, by age.
Map of chronostratigraphic divisions of India

North American plate

North American cratons and basement rocks.

South American plate

References

  1. ↑ Tetsuzo Seno, Taro Sakurai, and Seth Stein. 1996. Can the Okhotsk plate be discriminated from the North American plate? J. Geophys. Res., 101, 11305-11315 (abstract)
  2. ↑ Bird, P. (2003). "An updated digital model of plate boundaries". Geochemistry, Geophysics, Geosystems 4 (3): 1027. doi:10.1029/2001GC000252. http://peterbird.name/publications/2003_PB2002/2003_PB2002.htm.
  3. ↑ Timothy M. Kusky; Erkan Toraman & Tsilavo Raharimahefa (2006-11-20). "The Great Rift Valley of Madagascar: An extension of the Africa–Somali diffusive plate boundary?". International Association for Gondwana Research Published by Elsevier B.V.
  4. ↑ Niels Henriksen; A.K. Higgins; Feiko Kalsbeek; T. Christopher R. Pulvertaft (2000). "Greenland from Archaean to Quaternary" (PDF) (185). Greenland Survey Bulletin. Archived from the original (PDF) on 2008-12-07. Retrieved 2009-10-04.
  5. 1 2 Benford, B.; DeMets, C.; Calais, E. (2012). "GPS estimates of microplate motions, northern Caribbean: evidence for a Hispaniola microplate and implications for earthquake hazard" (PDF). Geophysical Journal International. Oxford, UK: Oxford University Press. 191 (2): 481–490. doi:10.1111/j.1365-246X.2012.05662.x. ISSN 0956-540X. Retrieved August 20, 2018.
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