*Yongsheng HUANG^1,2、Satoshi Okumura³、Kazuhisa Matsumoto³、Naoko Takahashi³、Hong Tang⁴、Tatsumi Tsujimori^3,5、Michihiko Nakamura³、Yuan Li^1,2 (1.Guangzhou Institute of Geochemistry, Chinese Academy of Sciences、2.CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China、3.Department of Earth Science, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan、4.South China Sea Environmental Monitoring Center, SOA, Guangzhou 510300, China.、5.Center for North Asian Studies, Tohoku University, Sendai, 980-8576, Japan)