Tearing up Rodinia: the Neoproterozoic palaeogeography of South American cratonic fragments

Abstract

AbstractRodinia was initially defined as a long‐lived supercontinent that assembled all the continental fragments around Laurentia and remained stable from 1000 up to 750 Ma. Nonetheless, recent work has cast doubt on the Rodinia palaeogeography and even on the timing of its assembly and break‐up. The geochronological and palaeomagnetic databases accumulated for South America and Africa in the last decade show that most of these continental fragments were not part of Rodinia. A wide Brasiliano Ocean separated most of the South American and African cratons from the Laurentia − Amazonia − Rio Apa −West Africa margin. This ocean was closed between 940 and 630 Ma along the Pampean–Paraguay–Araguaia–Pharusian mobile belts. Moreover, accretion along the South American and African platforms was a diachronous and long‐lived process that involved several intra‐oceanic and continental magmatic arcs and microcontinents. This evolution started at around 1000 Ma and ended at around 520 Ma with the final assembly of Gondwana.