TheEurasian plateis atectonic platethat includes most ofEurasia(alandmassconsisting of the traditionalcontinentsofAsiaandEurope), with the notable exceptions of theArabian Peninsula,theIndian subcontinent,and the area east of theChersky Rangein easternSiberia.It also includesoceanic crustextending westward to theMid-Atlantic Ridgeand northward to theGakkel Ridge.
| Eurasian plate | |
|---|---|
 Eurasian plate | |
| Type | Major |
| Approximate area | 67,800,000 km2(26,200,000 sq mi)[1] |
| Movement1 | South |
| Speed1 | 7–14 mm (0.28–0.55 in)/year |
| Features | Asia(excluding theArabian Peninsula,theIndian subcontinent,and the area east of theChersky Rangein easternSiberia),Europe(including a part ofIceland),Arctic Ocean,Atlantic Ocean |
| 1Relative to theAfrican plate | |
Boundaries
editThe western edge is atriple junctionplate boundarywith theNorth American plateandNubian plateat the seismically activeAzores triple junctionextending northward along theMid-Atlantic RidgetowardsIceland.[2][3]Ridges like the Mid-Atlantic ridge form at adivergent plate boundary.They are located deep underwater and very difficult to study. Scientists know less aboutocean ridgesthan they do the planets of the solar system.[4]
There is anothertriple junctionwhere the Eurasian plate meets theAnatolian sub-plateand theArabian plate.The Anatolian sub-plate is currently being squeezed by the collision of the Eurasian plate with the Arabian plate in theEast Anatolian Fault Zone.[5][6]
The boundary between the North American plate and the Eurasian plate in the area around Japan has been described as "shifty".[7]There are different maps for it based on recent tectonics, seismicity and earthquakefocal mechanism.The simplest plate geometry draws the boundary from theNansen Ridgethrough a broadzone of deformationin North Asia to theSea of Okhotskthen south throughSakhalin IslandandHokkaidoto the triple junction in theJapan Trench.[8]But this simple view has been successfully challenged by more recent research. During the 1970s, Japan was thought to be located on the Eurasian plate at a quadruple junction with the North American plate when the eastern boundary of the North American plate was drawn through southernHokkaido.New research in the 1990s supported that theOkhotsk microplatewas independent from the North American plate and aboundarywith theAmurian microplate,sometimes described as "a division within the Eurasian plate"[additional citation(s) needed]with an unknown western boundary.[9][10]
All volcanic eruptions in Iceland, such as the 1973 eruption ofEldfell,the 1783 eruption ofLakiand the 2010 eruption ofEyjafjallajökull,are caused by the North American and the Eurasian plates moving apart, which is a result ofdivergent plate boundaryforces.
Theconvergent boundarybetween the Eurasian plate and theIndian plateformed the Himalayas mountain range. The geodynamics ofCentral Asiais dominated by the interaction between the Eurasian plate and the Indian plate. In this area, many sub-plates or crust blocks have been recognized, which form theCentral Asianand theEast Asiantransit zones.[11]
See also
edit
References
edit- ^"Sizes of Tectonic or Lithospheric Plates".Geology.about. 2014-03-05. Archived fromthe originalon 2016-06-05.Retrieved2015-12-26.
- ^F.O. Marques, J.C. Catalão, C.DeMets, A.C.G. Costa, A. Hildenbrand (2013)."GPS and tectonic evidence for a diffuse plate boundary at the Azores Triple Junction"(PDF).Earth and Planetary Science Letters.381:177–187.Bibcode:2013E&PSL.381..177M.doi:10.1016/j.epsl.2013.08.051.
{{cite journal}}:CS1 maint: multiple names: authors list (link) - ^Machado, Adriane; Azevedo, José M. M.; Alemeida, Delia P.M.; Farid Chemale Jr. (2008)."Geochemistry of Volcanic Rocks from Faial Island (Azores)"(PDF).Lisbon: e-Terra, GEOTIC – Sociedade Geológica de Portugal. pp.1–14. Archived fromthe original(PDF)on 11 May 2011.Retrieved17 April2010.
- ^"Plate Boundaries".education.nationalgeographic.org.
- ^"Eastern Turkey IRIS Report".atlas.geo.cornell.edu.
- ^"The Bekten Fault: the palaeoseismic behaviour and kinematic characteristics of an intervening segment of the North Anatolian Fault Zone, Southern Marmara Region, Turkey".Geodinamica Acta.28(4). 2016.doi:10.1080/09853111.2016.1208524.
The Anatolian tectonic block (sub-plate) is being affected by converging plate movements that occur between the Arabian-African and Eurasian plates (e.g. Armijo, Meyer, Hubert, & Barka, Citation1999; Bozkurt, Citation2001; Jackson & McKenzie, Citation1984; Le Pichon, Chamot-Rooke, Lallemant, Noomen, & Veis, Citation1995; McKenzie, Citation1972, 1978; Şengör, Citation1979, 1980; Sengör, Görür, & Saroglu, Citation1985; Taymaz, Jackson, & McKenzie, Citation1991). As a result of this collision, the North Anatolian (NAF) and East Anatolian (EAF) transform faults have been formed. The Anatolian sub-plate is bounded to the north and east by these faults. The impingement started to move the sub-plate westward and resulted compression and uplifts near the Karlıova triple junction in the Eastern Anatolia. As a result of anti-clockwise rotational movement of the Anatolian sub-plate in a westward direction four different neotectonic regions have been formed namely: (1) East Anatolian compressional region, (2) North Anatolian region, (3) Central Anatolian 'ova' region and (4) West Anatolian extensional region (Sengör et al., Citation1985).
- ^Van Horne, A.; Sato, H.; Ishiyama, T.; Kato, N. (December 2015)."The Problem With the Plate Boundary in the Sea of Japan".AGU Fall Meeting AbstractsT31B-2879.
Hence, the problem: geodetic models imply a plate boundary between Japan and Eurasia, but published geological and seismological evidence does not support placing it in the Japan Sea or at the ISTL. If, as studies show, almost half of the convergence between North America and Eurasia is taken up in Hokkaido and across N Japan, the small amount of remaining convergence may be difficult to distinguish given the large elastic response in the upper plate (N Honshu) after the 2011 Tohoku-oki (M9.0) earthquake, and strong coupling at the megathrust. To draw such a plate boundary on tectonic maps implies a degree of certainty about its location which is unfounded
- ^Chapman, Michael E.; Solomon, Sean C. (February 10, 1976)."North American-Eurasian Plate Boundary in Northeast Asia"(PDF).Journal of Geophysical Research.81(5).Retrieved9 February2024.
- ^Barnes, Gina L. (2022).Tectonic Archaeology: Subduction Zone Geology in Japan and Its Archaeological Implications.Archaeopress Publishing Limited. pp.35–6.
- ^Volcanic and Tectonic Hazard Assessment for Nuclear Facilities.Cambridge University Press. p. 164.
- ^"Up-to-Date Geodynamics and Seismicity of Central Asia" by Y. Gatinsky, D. Rundquist, G. Vladova, T. Prokhodova