*Yoshihiro Iijima¹, Tetsuya Hiyama², Hiroki Takakura³ (1.Institute of Arctic Climate and Environment Research, Japan Agency for Marine-Earth Science and Technology, 2.Institute for Space-Earth Environmental Research, Nagoya University, 3.Center for Northeast Asian Studies, Tohoku University)

*Wataru Tanikawa¹, Yoko Ohtomo², Yuki Morono¹, Glen Snyder³, Yusuke Kubo⁴, Yoshihiro Iijima⁴, Hinrichs Kai-Uwe⁵, Fumio Inagaki¹ (1.Japan Agency for Marine-Earth Science and Technology, Kochi Instutute for Core Sample Research, 2.Faculty of Engineering, Hokkaido University, 3.Gas Hydrate Research Lab, Meiji Univeristy, 4.Japan Agency for Marine-Earth Science and Technology, 5.Center for Marine Environmental Sciences (MARUM), University of Bremen)