[S07-8] Strong motion and seismic sources I

[S07-8-02] Strong ground motions due to the 2016 mid Tottori prefecture earthquake, Japan

^○Takao Kagawa, Tatsuya Noguchi, Shohei Yoshida, Hiroshi Ueno, Sho Nakai, Kazu Yoshimi, Shoya Arimura, Shinji Yamamoto (Tottori University, Tottori, Japan)

An earthquake with Mj 6.6 hit mid area of Tottori prefecture, Japan on October 21st., 2016. In the area, earthquake swarms have been activated since mid October in 2015. Large number of seismometers installed by the prefectural government, JMA(Japan Meteorological Agency), NIED(National Institute for Earth Science and Disaster Resilience) and Tottori University, observed strong ground motions in the area. We also conducted aftershock observations just after the main shock at several temporary sites in the area with housing damages. From prompt analysis of the observed strong motions, it is understood that the ground motions were affected strongly by local site conditions, especially their predominant period caused by sedimentary response. The observed predominant periods at strong motion sites agree well with those estimated by previously conducted microtremor observations by ourselves. We will report characteristics of the observed ground motion and structural damages due to the earthquake considering effect of surface geology in the area.