ACKNOWLEDGEMENTS

This work was supported by the National Natural Science Foundation of China through grant 49904007and the National Major Fundamental Research and Development project（G20000467）.(https://www.daowen.com)

Dr.T.Shipley of UTIG provided original seismic data and a lot of help.We thank him very much.The first author was partly supported by STA fellowship，CAS foundation of national-wide excellent Ph.D.Dissertations.The first author is grateful to JST and JISTEC during his STA fellowship.The authors would like to thank Dr.Okuda，Dr.Tanahashi，Dr.Kano，Mr.Shimizu of Geological Survey of Japan for their help.