[S-SS09] Strong Ground Motion and Earthquake Disaster

[SSS09-P13] Ground motion characteristics and underground structure and near the Gomura fault that appeared in the 1927 Northern Tango Earthquake

*Takao Kagawa¹, Yukako Suehisa¹, Tatsuya Noguchi¹ (1.Tottori University, Faculty of Engineering)

Keywords:Gomura fault, ground motion characteristics , underground structure

The 1927 Northern Tango Earthquake (M7.3) caused surface faults in Gomura and Yamada area. Of these, the Gomura fault is preserved as a national natural monument in the Higuchi, Koike, and Ikunouchi districts. Microtremor observations (3 components single stations and arrays) across the fault were carried out in the Higuchi and Koike districts. As a result, in the Koike district, vertical displacement similar to that of the ground surface was observed at a depth of about 8 meters underground. Also as in the vicinity of other surface faults such as the Shikano and Yoshioka faults in the 1943 Tottori Earthquke, an anisotropy was observed in the amplitude of the two horizontal components, and the dominant peak of the microtremor H/V was found to be small in the vicinity of the fault. Gravity anomaly observation also conducted around the area, and a comprehensive interpretation will be carried out.