Evolution of the South China Paleocontinent and Related Resource-Environmental Developments:From Columbia to Gondwana
[Objective]Amalgamation and fragmentation cycles of the global supercontinents from the Proterozoic to Early Paleozoic are profoundly related to the geological evolution and distribution of massive economic resources in South China Block.[Methods]In this study,we examined the tectonic framework of the South China Block and relat-ed processes of geodynamic evolution and their impact on resource formation and environmental development in the context of assembly and breakup of the global supercontinents.[Results and Conclusions]The Yangtze Block of South China experienced similar tectonic events to the Laurentia breakup during the Early Paleoproterozoic,implying their close affinity before the Columbia(Nuna)assembly.Although the impact of tectonic evolution exists in different parts,the Yangtze Block recorded the assembly and breakup of the Columbia supercontinent,whereas the Cathyasia Block only shows the records of subduction-collision related to the supercontinental assembly.Before ca.820 Ma,a re-gional unconformity developed along the southeastern margin of the Yangtze Block,and the onset of sedimentary over-lap represented a new cycle of basin evolution since the breakup of the Rodinia supercontinent.Subsequently,the South China Block experienced five evolutionary periods,represented from old to young by(a)the embryonic-to-young rift(820-800 Ma),(b)mature rift(800-720 Ma),(c)early glacial(720-660 Ma),(d)interglacial(660-650 Ma),and(e)late glacial periods(650-635 Ma).The South China Block experienced an Early Paleozoic orogen that was closely associated with the Gondwana assembly and was close to Australia or India.Critical geological events in South China such as the Neoproterozoic Snowball Earth are considered tightly linked to the Rodinia breakup,whereas Precambrian giant economic deposits of Cu,Fe,and Mn were largely controlled by the magmatic-sedimenta-ry events.Furthermore,successive uplift-subsidence processes promoted the formation and evolution of Paleozoic sed-imentary basins with high-quality source rocks,large-scale reservoirs,and seals,which are critical for the develop-ment of hydrocarbon resources.
Colombia supercontinentRodinia supercontinentGondwana ContinentYangtze BlockCathaysia BlockProterozoic to Early Paleozoic
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