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The African plate, also known as the Nubian plate, is a major tectonic plate that includes most of the continent of Africa (except for its East Africa) and the adjacent oceanic crust to the west and south. It also includes a narrow strip of Western Asia along the Mediterranean Sea, including much of Israel and Lebanon. It is bounded by the North American plate and South American plate to the west (separated by the Mid-Atlantic Ridge); the Arabian plate and Somali plate to the east; the Eurasian plate, Aegean Sea plate and Anatolian plate to the north; and the Antarctic plate to the south.
Between and , the Somali plate began rifting from the African plate along the East African Rift. Since the continent of Africa consists of crust from 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.
The African plate includes several , stable blocks of old crust with deep roots in the subcontinental lithospheric mantle, and less stable terranes, which came together to form the African continent during the assembly of the supercontinent Pangaea around 250 million years ago. The cratons are from south to north, the Kalahari craton, Congo craton, Tanzania craton and West African Craton. The cratons were widely separated in the past, but came together during the Pan-African orogeny and stayed together when Gondwana split up. The cratons are connected by Orogeny, regions of highly deformed rock where the tectonic plates have engaged.
The Saharan Metacraton has been tentatively identified as the remains of a craton that has become detached from the subcontinental lithospheric mantle, but alternatively may consist of a collection of unrelated crustal fragments swept together during the Pan-African orogeny.
In some areas, the cratons are covered by sedimentary basins, such as the Tindouf Basin, Taoudeni Basin and Congo Basin, where the underlying archaic crust is overlaid by more recent Neoproterozoic sediments. The plate includes such as the Central African Shear Zone (CASZ) where, in the past, two sections of the crust were moving in opposite directions, and rifts such as the Anza trough where the crust was pulled apart, and the resulting depression filled with more modern sediment.
The African plate's speed is estimated at per year. It has been moving over the past 100 million years or so in a general northeast direction. It is pushing closer to the Eurasian plate, causing subduction where oceanic crust is converging with continental crust (e.g. portions of the central and eastern Mediterranean). In the western Mediterranean, the relative motions of the Eurasian and African plates produce a combination of lateral and compressive forces, concentrated in a zone known as the Azores–Gibraltar Fault Zone. 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 New England hotspot in the Atlantic Ocean has probably created a short line of mid- to late-Tertiary period age on the African plate but appears to be currently inactive.
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