African Plate

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The African Plate

The African Plate is a major tectonic plate. It includes much of the continent of Africa, as well as oceanic crust which lies between the continent and various surrounding ocean ridges. Since the continent of Africa includes both the African and the Somali plates, some literature refers to the African Plate as the Nubian Plate to distinguish it from the continent as a whole.[1]

Between 60 million years ago (mya) and 10 mya, the Somali Plate began rifting from the African Plate along the East African Rift.[2]

Map of East Africa showing some of the historically active volcanoes(red triangles) and the Afar Triangle (shaded, center) -- a triple junction where three plates are pulling away from one another: the Arabian Plate, the African Plate, and the Somali Plate (USGS)

One hypothesis suggests a mantle plume beneath the Afar region. Another hypothesis suggests the rifting is just a zone of weakness as the plates to its east move northwards.

The African Plate's speed is about 2.15 cm (0.85 in) per year.[3] It has been moving over the past 100 million years or so in a general northeast direction. This is drawing it closer to the Eurasian Plate. There is subduction where oceanic crust meets continental crust (in parts of the central and eastern Mediterranean).

Along its northeast margin, the African Plate is bounded by the Red Sea rift where the Arabian Plate is moving away from the African Plate.

The African, Somali and Arabian Plates were once all part of the great Gondwana southern supercontinent, as was the Indian subcontinent.

References[change | change source]

  1. Chu D. & Gordon R.G. 1999.. Evidence for motion between Nubia and Somalia along the Southwest Indian ridge journal = Nature. 398. pp. 64-67. doi:10.1038/18014. http://www.nature.com/nature/journal/v398/n6722/abs/398064a0.html. Retrieved June 2015. 
  2. "Somali Plate". Ashten Sawitsky. Retrieved June 2015.  Check date values in: |access-date= (help)
  3. Huang, Zhen Shao (1997). "Speed of the continental plates". The Physics Factbook. Glenn Elert. Retrieved February 2017.  Check date values in: |access-date= (help)