Institute of Mineralogy, Petrology and Economic Geology, Graduate School of Science, Tohoku University, 6-3 Aramaki-aza-Aoba, Aoba-ku, Sendai, 980-8578 Japan
Dipartimento Scienze Geologiche, Universita Roma Tre, Largo S.L., Murialdo, Roma, 100146 Italy
Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University, 6-3 Aramaki-aza-Aoba, Aoba-ku, Sendai, 980-8578 Japan
Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University, 6-3 Aramaki-aza-Aoba, Aoba-ku, Sendai, 980-8578 Japan
Earthquake Research Institute, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032 Japan
Faculty of Education, Fukushima University, 1 Kanayagawa, Fukushima, 960-1296 Japan
Department of Geoscience, Shimane University, 1060 Nishi-Kawazu-cho, Matsue, 690-8504 Japan
Geological Survey of Japan, AIST, Tsukuba Central 7, 1-1-1 Higashi, Tsukuba, 305-8567 Japan