COLUMBIA, RODINIA AND GONDWANA: INDIA'S PLACE IN 3 SUPERCONTINENTS

The interval of geological time spanning Geon20 to Geon5 witnessed the formation of three large continental landmasses. The earliest of the three, Columbia amalgamated between Geon20 and Geon18 and was at least partially dispersed during Geon15. Most of the landmasses then reassembled into a near ‘identical twin’ supercontinent of Rodinia beginning at Geon11. Rodinia’s breakup around Geons8-7 resulted in a drastic reorganization of continental crust that culminated with the formation of Gondwana by Geon5.

Peninsular India is featured in all three supercontinents and the supercontinent of Gondwana is named for a tribal region in India. The paleogeography of India within both Rodinia and Columbia are problematic and India is traditionally placed along the margins of both supercontinents. In the past decade, the Proterozoic paleomagnetic database for most continents has improved dramatically (including India). These new data, combined with new and existing paleomagnetic data from other landmasses allow us to assess (albeit in preliminary fashion), the role India in the Columbia, Rodinia and Gondwana supercontinents. In this presentation, we will highlight India's place within these supercontinents and discuss issues related to both the archetypal "Rodinia" and "Columbia" supercontinental configurations and their alternatives. We highlight potential biases in our view of the earliest supercontinents such as the 'strange attractor' connections between Baltica, Laurentia and Siberia. We also note the 'spiritual interloper' status of other continental landmasses in the proposed configurations of Columbia and Rodinia and propose some alternative viewpoints on the search for ancient supercontinents and the supercontinental cycle.