*Katsunori Yanagawa¹, Atsushi Tani², Naoya Yamamoto², Akihiro Hachikubo³, Akihiro Kano¹, Ryo Matsumoto⁴, Yohey Suzuki⁵ (1.Graduate School of Social and Cultural Studies, Kyushu University, 2.Department of Earth and Space Science, Graduate School of Science, Osaka University, 3.Environmental and Energy Resources Research Center, Kitami Institute of Technology, 4.Gas Hydrate Laboratory, Meiji University, 5.Department of Earth and Planetary Science, University of Tokyo)

*Atsushi Tani¹, Kyohei Yamada¹, Hitoshi Tomaru², Takeshi Oi³, Ryo Matsumoto³ (1.Graduate School of Science, Osaka University, 2.Graduate School of Science, Chiba University, 3.Gas Hydrate Laboratory, Meiji University)