South China Seabasin opening: Lithospheric rifting and interactionwith surroundingsubduction zones
LIN Jian1,2,3,4, SUN Zhen1,3,5, LI Jiabiao6, ZHOU Zhiyuan1,3,5, ZHANG Fan1,3,5, LUO Yiming1,3,4
1. Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China;
2. Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA;
3. Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou), Guangzhou 511458, China;
4. Department of Ocean Science and Engineering, Southern University of Science and Technology of China, Shenzhen 518055, China;
5. Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 510301, China;
6. Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
Abstract:The South China Sea (SCS) is the largest marginal sea in the western Pacific Ocean. Significant breakthroughs have been made in the SCS researches, especially through the South China Sea Deep Initiative and International Ocean Discovery Program (IODP). One of the surprising discoveries is that the expected mantle serpentinites at the IODP drill sites are not found at the northern SCS continental margin; instead, the magma is found to erupt rapidly, indicating the significant magmatism at the SCS soon after the continental rifting and probably due to the strong influence of surrounding subduction zones. Thus, the SCS might be regarded as a new type of rift basin of "plate-edge rifting", different from the classic Atlantic type of "intra-plate rifting". It is also suggested that the subduction-induced mantle upwelling is likely to play an important role in the magmatism of the SCS.
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