Proterozoic Eastern Ghats Belt, India – a witness of multiple orogenies and its lineage with ancient supercontinents

Somnath Dasgupta, Subrata Karmakar, Sankar Bose, and Kaushik Das

The Eastern Ghats Belt of India exposes a deep crustal section that witnessed multiple events of deformation, magmatism and metamorphism throughout the Proterozoic eon. Structural and petrological styles show variations in both, space and time. Available petrological data suggest that the deep crustal section of this belt was subjected to extreme thermal perturbation causing high temperature (HT) to ultrahigh temperature (UHT) metamorphism over an extended geographical area, the nature of which again varied in time and space. It is now understood that the 1000km long edifice of the Eastern Ghats Belt evolved in a phase-wise manner due to recurrent crust-building activities surrounding cratonic India. Consequently, it is possible to correlate these events with global-scale orogenies that united India with east Antarctica and Australia in different time and space coordinates. This prompts us to a hypothesis that history of such a mountain belt can actually reflect the evolution of Precambrian supercontinents, namely Columbia, Rodinia and Gondwana. We review the present state-of-the-art, but also point out that more rigorous investigation in future may add a quantitative flavor to this.