Nozomi HATANO¹, *Kohki YOSHIDA², Eiji SASAO³, Yoshiko ADACHI⁴, Hideki IWANO⁵, Toru DANHARA⁵ (1.Division of Science and Technology, Graduated School of Shinshu University, 2.Department of Geology, Shinshu University, 3.Japan Atomic Energy Agency, 4.Faculty of Science, Niigata University, 5.Kyoto Fission-Track Co.Ltd)

*Nozomi HATANO¹, Kohki YOSHIDA², Yoshiko ADACHI³ (1.Division of Science and Technology, Graduated School of Shinshu University, 2.Development of Geology, Shinshu University, 3.Faculty of Science, Niigata University)