The Dynamic response of Horonobe Underground Research Center during the 2018 June 20 earthquake

Sato, Toshinori  ; Aoyagi, Kazuhei  ; Miyara, Nobukatsu; Aydan, mer*; Tomiyama, Jun*; Morita, Tatsuri*

An earthquake with a moment magnitude of 4 occurred in June 20, 2018, which is also named as the 2018 June 20 Soya Region earth-quake. The strong motions induced by this earthquake were recorded by the accelerometers installed in the Horonobe URL as well as the Kik-Net and K-Net strong motions networks operated by the National Research Institute for Earth Science and Disaster Prevention of Japan. The authors explain the results of the analyses carried out on the ground amplification and frequency characteristics of the acceleration records at the Horonobe URL and those of the Kik-net strong motion station and the structural effect of the URL on the ground amplification and frequency characteristics. Furthermore, the authors discuss the implications of the results obtained from this study in practice and the safety of the nuclear waste disposal at depth.