*Masatsugu Ogasawara¹, Takeshi Nakajima², Kenji Horie³, Mami Takehara³, Yuichiro Suzuki², Takayuki Sawaki², Mitsuyoshi Kaneko⁴, Satoshi Nakanishi⁴, Hiroyuki Mitsuishi⁴, Nobuaki Monzawa⁴, Tetsuo Fukano⁴ (1.Institute of Geology and Geoinformation, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 2.Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 3.National Institute of Polar Research, 4.JX Nippon Oil & Gas Exploration Corporation)

*Kenji Horie^1,2, Mami Takehara¹ (1.National Institute of Polar Research, 2.Department of Polar Science, The Graduate University for Advanced Studies (SOKENDAI))

*Mami Takehara¹, Kenji Horie^1,2,3 (1.National Institute of Polar Research, 2.The Graduate University for Advanced Studies (SOKENDAI), 3.Japan Agency for Marine-Earth Science and Technology (JAMSTEC))

*Satoshi Yoshimaru¹, Shoichi Kiyokawa¹, Takashi Ito², Minoru Ikehara³, Kenji Horie⁴, Mami Takehara⁴, Takashi Sano⁵, Frank K Nyame⁶, George M Tetteh⁷ (1.Department of Earth and Planetary Science, Kyushu University, 2.Ibaraki University, 3.Kochi University, 4.National Institute of Polar Resarch, 5.National Museum of Nature and Science, 6.University of Ghana, 7.University of Mining and Technology)