1. Department of Earth Sciences, Graduate School of Science; Chiba University; 1-33 Yayoi Inage Chiba 263-8522 Japan
2. Institute for Geothermal Sciences; Kyoto University; Noguchibaru Beppu 874-0903 Japan
3. Department of Geology and Mineralogy, Graduate School of Science; Kyoto University; Kitashirakawa-Oiwake-cho Sakyo-ku Kyoto 606-8502 Japan
4. Geochemical Research Center; University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
5. Center for Northeast Asian Studies; Tohoku University; 41 Kawauchi Aoba-ku Sendai 980-8576 Japan
6. School of Earth Sciences; Peking University; Beijing 100871 China
7. Institute of Tectonics and Geophysics (Far Eastern Branch, Russian Academy of Sciences); 65 Kim Yu Chen Str. Khabarovsk 680063 Russian Federation
8. Department of Earth Sciences, Faculty of Science; Kanazawa University; Kakuma Kanazawa 920-1192 Japan