Journal of the Geological Society of Japan Journal of the Geological Society of Japan, Geological Society of Japan, 2019, 125 (1), pp.5-22. ⟨10.5575/geosoc.2018.0056⟩ Journal of the Geological Society of Japan, 2019, 125 (1), pp.5-22. ⟨10.5575/geosoc.2018.0056⟩