*Masao Nakanishi¹, Takemi Ishihara² (1.Department of Earth Sciences, Graduate School of Science, Chiba University, 2.Institute of Geology and Geoinfomation, National Institute of Advanced Industrial Science and Technology )

*Megumi Fujimoto¹, Masao Nakanishi² (1.Graduate School of Science and Engineering, Chiba University , 2.Department of Earth Sciences Graduate School of Science, Chiba University)

*Takashi Sano¹, Maria Luisa Tejada², Clive R. Neal³, Millard Coffin⁴, Masao Nakanishi⁵, Peter J. Michael⁶, Jörg Geldmacher⁷, Takeshi Hanyu², Seiichi Miura², Christian Timm⁸, Anthony A. P. Koppers⁹, Daisuke Suetsugu², Takashi Tonegawa², Akira Ishikawa¹⁰, Kenji Shimizu², Paterno Castillo¹¹ (1.National Museum of Nature and Science, 2.Japan Agency for Marine-Earth Science and Technology, 3.University of Notre Dame, USA, 4.University of Tasmania, Australia, 5.Chiba University, 6.The University of Tulsa, USA, 7.GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany, 8.GNS Science, New Zealand, 9.Oregon State University, USA, 10.Tokyo Institute of Technology, 11.Scripps Institution of Oceanography, UCSD, USA)