List of tectonic plates

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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.

Components[edit]

  • Continent – Very large landmass identified by convention
  • Continental crust – Layer of rock that forms the continents and continental shelves
  • Craton – Old and stable part of the continental lithosphere
  • Crust – The outermost solid shell of a rocky planet, dwarf planet, or natural satellite
  • Lithosphere – The rigid, outermost shell of a terrestrial-type planet or natural satellite that is defined by its rigid mechanical properties
  • Mantle – The part of the interior of a planet between the crust and the core
  • Oceanic crust – The uppermost layer of the oceanic portion of a tectonic plate
  • Shield – A large stable area of exposed Precambrian crystalline rock
  • Supercontinent – Landmass comprising more than one continental core, or craton
  • Tectonic plate – Continuous section of the lithosphere of the Earth which is moving relative to adjacent plates
  • Terrane – Fragment of crustal material formed on, or broken off from, one tectonic plate and accreted or "sutured" to crust lying on another plate

Current plates[edit]

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[edit]

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[edit]

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.

  • Somali Plate – Minor tectonic plate including the east coast of Africa and the ajoining seabed – 16,700,000 km2
  • Nazca Plate – Oceanic tectonic plate in the eastern Pacific Ocean basin – 15,600,000 km2
  • Philippine Sea Plate – An oceanic tectonic plate to the east of the Philippines – 5,500,000 km2
  • Arabian Plate – A tectonic plate consisting mostly of the Arabian Peninsula, extending northward to the Levant – 5,000,000 km2
  • Caribbean Plate – A mostly oceanic tectonic plate including part of Central America and the Caribbean Sea – 3,300,000 km2
  • Cocos Plate – A young oceanic tectonic plate beneath the Pacific Ocean off the west coast of Central America – 2,900,000 km2
  • Caroline Plate – Minor oceanic tectonic plate north of New Guinea – 1,700,000 km2
  • Scotia Plate – Minor oceanic tectonic plate between the South American and Antarctic Plates – 1,600,000 km2
  • Burma Plate – A minor tectonic plate in Southeast Asia – 1,100,000 km2
  • New Hebrides Plate – Minor tectonic plate in the Pacific Ocean near Vanuatu – 1,100,000 km2

Microplates[edit]

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
  • 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
  • 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
    • Mariana Plate – A small tectonic plate west of the Mariana Trench
    • Philippine Mobile Belt, also known as Philippine Microplate – Complex portion of the tectonic boundary between the Eurasian Plate and the Philippine Sea Plate, comprising most of the country of the Philippines
  • South American Plate
    • Altiplano Plate
    • Falklands Microplate
    • North Andes Plate – A small tectonic plate in the northern Andes

Ancient continental formations[edit]

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[edit]

Supercontinent – Landmass comprising more than one continental core, or craton

The following list includes the supercontinents known or speculated to have existed in the Earth's past:

  • Columbia – Ancient supercontinent of approximately 2,500 to 1,500 million years ago
  • Euramerica – minor supercontinent formed in the Devonian by collision between the Laurentian, Baltica, and Avalonia cratons
  • Gondwana – Neoproterozoic to Carboniferous supercontinent
  • Kenorland – Hypothetical Neoarchaean supercontinent from about 2.7 billion years ago
  • Laurasia – Northern supercontinent that formed part of the Pangaea supercontinent
  • Nena – Early Proterozoic supercontinent
  • Pangaea – Supercontinent from the late Paleozoic to early Mesozoic eras
  • Pannotia – Hypothesized Neoproterozoic supercontinent from the end of the Precambrian
  • Proto-Laurasia
  • Rodinia – Hypothetical neoproterozoic supercontinent from between about a billion to about three quarters of a billion years ago
  • Ur – Proposed archaean supercontinent from about 3.1 billion years ago
  • Vaalbara – Archaean supercontinent from about 3.6 to 2.7 billion years ago

Ancient plates and cratons[edit]

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[edit]

Antarctica plate[edit]

  • Bellingshausen Plate – An ancient tectonic plate that fused onto the Antarctic Plate
  • Charcot Plate – A fragment of the Phoenix tectonic plate fused to the Antarctic Peninsula
  • East Antarctic Shield, also known as East Antarctic Craton – A cratonic rock body which makes up most of the continent Antarctica
  • Phoenix Plate – Ancient tectonic plate that existed during the mid-Cretaceous through early Cenozoic time; the remainder of the plate is now located east of the Drake Passage/Shackleton Fracture Zone

Eurasian plate[edit]

Indo-Australian plate[edit]

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

North American plate[edit]

North American cratons and basement rocks.
  • Avalonia – A microcontinent in the Paleozoic era (Canada, Great Britain, and United States)
  • Carolina Plate – An exotic terrane from central Georgia to central Virginia in the United States
  • Churchill Craton – The northwest section of the Canadian Shield from southern Saskatchewan and Alberta to northern Nunavut (Canada)
  • Farallon Plate – An ancient oceanic plate that has mostly subducted under the west coast of the North American Plate (split into the Cocos, Explorer, Juan de Fuca, Gorda Plates, Nazca Plate, and Rivera Plates)
  • Florida Plate (United States)
  • Hearne Craton – A craton in northern Canada which, together with the Rae Craton, forms the Western Churchill Province (Canada)
  • Laurentian Craton, also known as North American Craton – A large continental craton that forms the ancient geological core of the North American continent (Canada and United States)
  • Insular Plate – Ancient oceanic plate that began subducting under the west-coast of North America around the early Cretaceous time
  • Intermontane Plate – Ancient oceanic tectonic plate on the west coast of North America about 195 million years ago
  • Izanagi Plate – An ancient tectonic plate, which was subducted beneath the Okhotsk Plate
  • Mexican Plate
  • Nain Province – Part of the North Atlantic Craton in Labrador, Canada (Canada)
  • Newfoundland Plate
  • North Atlantic Craton – An Archaean craton exposed in southern West Greenland, the Nain Province in Labrador, and the Lewisian complex in northwestern Scotland
  • Nova Scotia Plate
  • Rae Craton – An Archean craton in northern Canada north of the Superior Craton (Canada)
  • Sask Craton (Canada)
  • Sclavia Craton – A late Archean supercraton thought to be parental to the Slave and Wyoming Cratons in North America, the Dharwar Craton in southern India, and the Zimbabwe Craton in southern Africa (Canada)
  • Slave Craton – An Archaean craton in the north-western Canadian Shield, in Northwest Territories and Nunavut (Canada)
  • Superior Craton – An Archean craton which forms the core of the Canadian Shield north of Lake Superior (Canada)
  • Wyoming Craton – A craton in the west-central United States and western Canada (United States)

South American plate[edit]

References[edit]

  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. ^ a b 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.

External links[edit]