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Assembly of Gondwana
The Madagascar Plate was formerly located in the central part of the supercontinent Gondwana. It contains part of the East African Orogen, which formed in the Neoproterozoic to Cambrian assembly of the Gondwana. This heavily influenced the geology of central and northern Madagascar

The entire island can be divided into four tectonic and geologic units : the Antongil block, Antananarivo block, Bekily Belt in the south, and Bemarivo Belt in the far north.

1-Antongil Block: characterized by a 3.2Ga gneiss intruded by granite that has undergone greenschist facies metamorphism.

2-Antananarivo Block: 2.5Ga gneiss layered with younger granitoids and gabbros. It has metamorphosed to granulite facies conditions.

3-Bemarivo Belt: contains two regions: metasedimentary gneisses in the southern part and granitic domes in the north.

4- Bekily Belt: is made up of mostly sedimentary protoliths and granulite and upper amphibolite grade gneisses

The blocks in the northern part of the island are made up of Archean cratonic material. The Antongil block has been linked with the Dharwar formation of India, however the Antananarivo block to the west has been too heavily altered to link easily to another continent.

The central part of the island contains metasediments from African and Indian continental shelves. This is the Itremo group, which also contains intrusions of material from the Antongil block. The Itremo sheet was folded in the amalgamation of Madagascar ~700Mya, and now contains upright folds, divergent reverse faults, and strike-slip faults.

Rifting
The Madagascar plate experienced two major rifting events during the break-up of Gondwana. First, it separated from Africa about 160Mya, then from the Seychelles and India 66-90Mya. The first rifting event, separation from Somalia and the rest of Africa, caused displacement along Davie Ridge, in the Mozambique Channel to the west of the islands, a now extinct transform. The rifting is also associated with extensive deformation as well as volcanism in the late Cretaceous and Cenozoic (Eocene to Miocene). The second separation caused volcanism in the southern part of the island as well as further south, such as on Marion Island. The volcanism was so extensive that in the late Cretaceous Madagascar may have been entirely covered in flood basalts from volcanism associated with this second rifting event. It was at this point in the end of the Cretaceous that Madagascar became entirely isolated from any other continent.

Modern Tectonics
Madagascar remains seismically and volcanically active. The most seismically active area is beneath the Ankaratra Plateau in the centre of the island, which experienced major (magnitude 5.2 and 5.5) earthquakes in 1985 and 1991. The Aloatra-Ankay rift to the north of the plateau is also seismically active, as well as the Davie Ridge off the coast, which is an extension of the East African Rift Zone.

The Ankaratra Plateau contains a major volcanic field with volcanic cones and extensive flows. It was active from the Neogene to the Quaternary. To the northwest, there are the recently active Comoro islands, which are hypothesized to be related to a hot spot.

The Madagascar plate now moves mostly in conjunction with the African plate, so some believe it should not be still considered an independent plate.