*Kazuhisa A. Chikita¹, Akio Goto², Jun Okada³, Satoshi Miura⁴, Mare Yamamoto⁴ (1.Arctic Research Center, Hokkaido University, 2.Center for Northeast Asian Studies, Tohoku University, 3.Volcanology Research Department, Meteorological Research Institute, , 4.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Faculty of Science, Tohoku University)

*Ryota Takagi¹, Akira Ishigami¹, Genti Toyokuni¹, Ryosuke Azuma¹, Mare Yamamoto¹ (1.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University)

*Akihiko Terada¹, Akira Katori¹, Muga Yaguchi², Mare Yamamoto³, Taishi Yamada⁴, Shin'ya Onizawa², Tatsuji Nishizawa¹, Hiroshi Aoyama⁵, Yuichi Morita⁷, Takeshi Ohba⁶ (1.Volcanic Fluid Research Center, School of Science, Tokyo Institute of Technology, 2.Meteorological Research Institute, JMA, 3.Graduate School of Science, Tohoku University, 4.Disaster Prevention Research Institute, Kyoto University, 5.Faculty of Science, Hokkaido University, 6.Department of chemistry, School of Science, Tokia University, 7.Earthquake Research Institute, University of Tokyo)

*Takeshi Nishimura¹, Kentaro Emoto¹, Hisashi Nakahara¹, Satoshi Miura¹, Mare Yamamoto¹, Shunsuke Sugimura¹, Takahiro Ueda¹, Ayumu Ishikawa¹, Tsunehisa KIMURA² (1.Graduate School of Science, Tohoku University, 2.Schlumberger)

*Mare Yamamoto¹ (1.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University)

*Takuma Ikegaya¹, Mare Yamamoto¹ (1.Graduate School of Science, Tohoku University)