*Tomohiro Toki¹, Ko Agena¹, Akira Ijiri², Juichiro Ashi³ (1.Faculty of Science, University of the Ryukyus, 2.JAMSTEC, 3.AORI)

*Akira Ijiri¹, Yohei Hamada¹, Tomohiro Toki², Ko Agena², Tatsuhiko Hoshino¹, Kyoko Hagino³, Hideaki Machiyama¹, Juichiro Ashi⁴, Fumio Inagaki¹ (1.Japan Agency for Marine-Earth Science and Technology, 2.University of the Ryukyus, 3.Kochi University, 4.The University of Tokyo)

*Tomohiro Toki¹, Ko Agena¹, Akira Ijiri², Juichiro Ashi³ (1.Faculty of Science, University of the Ryukyus, 2.JAMSTEC, 3.AORI)

*Yusuke Miyajima^1,3, Yumiko Watanabe¹, Akira Ijiri², Akiko S Goto³, Robert Jenkins³, Takashi Hasegawa³, Saburo Sakai⁴, Ryo Matsumoto⁵ (1.Department of Geology and Mineralogy, Division of Earth and Planetary Sciences, Graduate school of Science, Kyoto University, 2.Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 3.School of Natural System, College of Science and Engineering, Kanazawa University, 4.Department of Biogeochemistry, JAMSTEC, 5.Gas Hydrate Laboratory, Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University)

*Takami Nobuhara¹, Kayoko Matsumura¹, Yasuo Kondo², Toyoho Ishimura³, Akira Ijiri⁴, Urumu Tsunogai⁵, Olev Vinn⁶, Steffen Kiel⁷, Crispin Little⁸ (1.Science Education (Geology), Faculty of Education, Shizuoka University, 2.Science Unit, Natural Sciences Cluster, Kochi University, 3.Department of Chemistry and Material Engineering, National Institute of Technology, Ibaraki College, 4.Japan Agency for Marine-Earth Science and Technology, 5.Graduate School of Environmental Studies, Nagoya University, 6.Department of Geology, University of Tartu, Estonia, 7.Department of Palaeobiology, Swedish Museum of Natural History, 8.School of Earth and Environment, University of Leeds)

*Takami Nobuhara¹, Kayoko Matsumura¹, Yasuo Kondo², Toyoho Ishimura³, Akira Ijiri⁴, Urumu Tsunogai⁵, Olev Vinn⁶, Steffen Kiel⁷, Crispin Little⁸ (1.Science Education (Geology), Faculty of Education, Shizuoka University, 2.Science Unit, Natural Sciences Cluster, Kochi University, 3.Department of Chemistry and Material Engineering, National Institute of Technology, Ibaraki College, 4.Japan Agency for Marine-Earth Science and Technology, 5.Graduate School of Environmental Studies, Nagoya University, 6.Department of Geology, University of Tartu, Estonia, 7.Department of Palaeobiology, Swedish Museum of Natural History, 8.School of Earth and Environment, University of Leeds)