A great amount of new S-wave data has been combined to image the mantle structure down to lower mantle depth near the southeastern margin of Eurasia and understand the tectonics in South China since the Mesozoic.Our r...A great amount of new S-wave data has been combined to image the mantle structure down to lower mantle depth near the southeastern margin of Eurasia and understand the tectonics in South China since the Mesozoic.Our results reveal a large-scale structure beneath the South China Sea,with a prominent,broad low-velocity feature of at least 1500-km wide in and below the mantle transition zone(MTZ)and a pronounced low-velocity feature of nearly 500-km wide in the lowermost mantle.Together these features may represent the head-and-tail of an upwelling mantle plume that has interacted with and deformed by the subducting plates in the region.The Andaman-Sumatra plate is seen subducting steeply without stagnation in the MTZ over the large-scale low-velocity structure,suggesting that the upwelling mantle may have exerted significant influence on the overlying plate tectonics.Our results suggest a long-term extensional regime near the southeastern margin of Eurasia,which may help to understand the formation of the large-scale intra-plate magmatism and mineralization with accumulation of huge amount of rare metal elements in South China during the Mesozoic,and the continental breakup,the southeastward extrusion of Indochina,and the opening of the South China Sea during the Cenozoic.展开更多
笔者利用虚拟仿真软件Multisim与MATLAB设计电桥的平衡模拟调节仿真模块,并最终整合模块形成电桥的虚拟仿真实验系统。该电桥平衡模拟调节仿真系统使用Qt C++工具设计图形用户界面(Graphical User Interface,GUI),系统运行在ARM(Advance...笔者利用虚拟仿真软件Multisim与MATLAB设计电桥的平衡模拟调节仿真模块,并最终整合模块形成电桥的虚拟仿真实验系统。该电桥平衡模拟调节仿真系统使用Qt C++工具设计图形用户界面(Graphical User Interface,GUI),系统运行在ARM(Advanced RISC Machines)嵌入式Linux硬件平台上。该系统可辅助教学和数据计算与处理,使得教学对象可以随时随地进行试验,有利于提高实验教学效率。展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2016YFC0600201)National Natural Science Foundation of China(Grant Nos.42174109,41674099,41974100,and 42174169)+1 种基金China Geological Survey(Grant No.DD20221829)U.S.NSF(Grant No.1927133)。
文摘A great amount of new S-wave data has been combined to image the mantle structure down to lower mantle depth near the southeastern margin of Eurasia and understand the tectonics in South China since the Mesozoic.Our results reveal a large-scale structure beneath the South China Sea,with a prominent,broad low-velocity feature of at least 1500-km wide in and below the mantle transition zone(MTZ)and a pronounced low-velocity feature of nearly 500-km wide in the lowermost mantle.Together these features may represent the head-and-tail of an upwelling mantle plume that has interacted with and deformed by the subducting plates in the region.The Andaman-Sumatra plate is seen subducting steeply without stagnation in the MTZ over the large-scale low-velocity structure,suggesting that the upwelling mantle may have exerted significant influence on the overlying plate tectonics.Our results suggest a long-term extensional regime near the southeastern margin of Eurasia,which may help to understand the formation of the large-scale intra-plate magmatism and mineralization with accumulation of huge amount of rare metal elements in South China during the Mesozoic,and the continental breakup,the southeastward extrusion of Indochina,and the opening of the South China Sea during the Cenozoic.
