Buried fragments reveal a “Greater Gondwana” supercontinent
Abstract
Profound global biogeochemical shifts marked the Ediacaran-Cambrian transition [550–500 million years (Ma)], a phenomenon often ascribed to the dynamics of supercontinent cycles. However, Gondwana is frequently denied supercontinent status due to its perceived spatial deficit (∼64% of continental landmass). Leveraging continental-scale Nd isotopic mapping based on a vast database of 25,346 felsic-intermediate igneous rocks, we reveal extensive buried Precambrian terranes beneath Phanerozoic orogens in Asia, Europe, and North America. Our results expand Gondwana’s reconstructed area to ∼80% of the global landmass, firmly establishing its identity as a true supercontinent—termed “Greater Gondwana.” We propose that the assembly and peripheral subduction of this “Greater Gondwana” played a pivotal role in driving the geodynamic and environmental perturbations that culminated in the Cambrian metazoan radiation.
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Authors: Tao Wang, William J. Collins, Chaoyang Wang, Zengqian Hou, Ying Tong, He Huang, Jieping Ye
Institutions: Curtin University, State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Zhejiang Lab, Beijing Institute of Geology for Mineral Resources