List of tectonic plates

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.

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]

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

North American plate

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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