*Arashi TAKI¹, Naoto HIRANO², Junji YAMAMOTO³, Shiki MACHIDA⁴, Teruaki ISHII⁵ (1.Graduate School of Science, Tohoku University, 2.Center for Northeast Asian Studies, Tohoku University, 3.Hokkaido University Museum, 4.Department of Resources and Environmental Engineering, Waseda University, 5.Fukada Geological Institute)

*Arashi TAKI¹, Naoto HIRANO², Junji YAMAMOTO³, Shiki MACHIDA⁴, Teruaki ISHII⁵ (1.Graduate School of Science, Tohoku University, 2.Center for Northeast Asian Studies, Tohoku University, 3.Hokkaido University Museum, 4.Department of Resources and Environmental Engineering, Waseda University, 5.Fukada Geological Institute)