India-Madagascar Separation: Breakup Along a Pre-existing Mobile Belt and Chipping of the Craton

摘要: Abstract Separation of India from other parts the Gondwanaland during past ∼150 m.y., can be characterized by thermomechanical interaction between continental lithosphere, particularly its mobile belts, and mantle plumes. It implies that, a combination belts plumes could often ‘fatal’ for supercontinental stability. For example, Eastern-Ghat belt (EGMB) Kerguelen/Crozet hotspots together seem to have facilitated India's separation Antarctica. In view this, on basis geophysical closely related data sets, it is suggested here that prior ∼90 Ma, Madagascar, along with westernmost margin South Indian shield, was also part network India. The latter consists Eastern-Ghat, Southern Granulite Terrain, Satpura Delhi-Aravalli belts. India-Madagascar breakup (at Ma) would taken place relatively corridor under influence Marion plume. This supported fact gravity anomalies, Moho depths, tectonics, seismic deformations over Madagascar are quite similar. study brings out anomalies geological features may allow better constraining juxtapositioning. Along eastern there exist two thin (∼25-75 km wide, nearly N-S trending) low-grade strips Archaean age crust, viz. Antongil block (in northeast) Masora (central-eastern part), which bounded west Betsimisaraka suture zone (BS). These represent boundary Dharwar craton, appear been chipped off because weakening tectosphere due episodic deformation metamorphism in Madagascar. Continental chipping cratonic margins globally applicable.