*Toru Takeshita1, Thomas Anthony Czertowicz1, Dong Van Bui1, Shun Arai2, Takafumi Yamamoto3, Jun-ichi Ando3, Norio Shigematsu4, Koichiro Fujimoto5
(1.Department of Natural History Sciences, Graduate School of Science, Hokkaido University, 2.Department of Earth Science, Graduate School of Science, Tohoku University, 3.Department of Earth and Planetary Systems Science, Hiroshima University, 4.Research Institute of Earthquake and Volcano Geology, Geological Society of Japan, Natural Institute of Advanced Industrial Science and Technology, 5.Tokyo Gakugei University)