1. Graduate School of International Resource Science; Akita University Akita; Japan
2. School of Natural Sciences; Södertörn University; Huddinge Sweden
3. Graduate School of Engineering Science; Akita University; Akita Japan
4. Department of Earth Sciences; Uppsala University; Uppsala Sweden
5. Atmosphere and Ocean Research Institute; University of Tokyo; Chiba Japan
6. Educational Development Center; Kogakkan University; Mie Japan
7. Geological Survey of Finland; Marine Geology; Espoo Finland
8. Department of Geosciences and Geography; University of Helsinki; Helsinki Finland
9. Institute for Applied Geophysics and Geothermal Energy; RWTH Aachen University; Aachen Germany