*Akira Ishikawa^1,2, Keiko Koshida, Katsuhiko Suzuki², Tetsuya Yokoyama¹, Tsuyoshi Komiya³ (1.Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2.Submarine Resources Research Center, Japan Agency for Marine-Earth Science and Technology, 3.Graduate School of Arts and Sciences, The University of Tokyo )

*Tetsu Kogiso¹, Akira Ishikawa², Norikatsu Akizawa³ (1.Kyoto University, 2.Tokyo Institute of Technology, 3.The University of Tokyo)

*Yuki Hibiya¹, Tsuyoshi Iizuka², Katsuhiko Suzuki¹, Shigekazu Yoneda³ (1.Submarine Resources Research Center, Japan Agency for Marine-Earth Science and Technology, 2.The University of Tokyo, 3.National Museum of Nature and Science)

*Katsuhiko Suzuki^1,5, Madhusoodhan Satish-Kumar², Trisrota Chaudhuri³, M. Jayananda⁴ (1.Submarine Resources Research Center, Japan Agency for Marine-Earth Science and Technology, 2.Department of Geology, Faculty of Science, Niigata University, 3.Department of Geology, University of Calcutta, 4.Centre Earth and Space Sciences, University of Hyderabad, 5.Department of Earth Sciences, Graduate School of Science, Tohoku University)

Yuri Mitsude¹, *Tatsuji Nishizawa², Hitomi Nakamura³, Tatiana Churikova⁴, Boris Gordeychik⁵, Akira Ishikawa⁶, Hikaru Iwamori¹ (1.Earthquake Research Institute, The University of Tokyo, 2.Volcanic Fluid Research Center, School of Science, Tokyo Institute of Technology, 3.Institute of Earthquake and Volcano Geology, Geological Survey of Japan, AIST, 4.Institute of Volcanology and Seismology, Far East Branch, RAS, 5.Institute of Experimental Mineralogy, RAS, 6.Department of Earth and Planetary Sciences, School of Science, Tokyo Institute of Technology)

*Tatsuji Nishizawa¹, Yuri Mitsude², Hitomi Nakamura³, Tatiana Churikova⁴, Boris Gordeychik⁵, Akira Ishikawa⁶, Hikaru Iwamori² (1.Volcanic Fluid Research Center, School of Science, Tokyo Institute of Technology, 2.Earthquake Research Institute, The University of Tokyo, 3.Institute of Earthquake and Volcano Geology, Geological Survey of Japan, AIST, 4.Institute of Volcanology and Seismology, Far East Branch, RAS, 5.Institute of Experimental Mineralogy, RAS, 6.Department of Earth and Planetary Sciences, School of Science, Tokyo Institute of Technology)