Characteristics of Strong Ground Motion and Subsurface Structure near the Yoshioka Fault of the 1943 Tottori Earthquake, Japan

Abstract

In this study, we conducted microtremor and gravity observations in the Otsuka area, Tottori City, to investigate the subsurface structure and characteristics of strong ground motion characteristics of microtremors in the vicinity of the Yoshioka fault of the Tottori Earthquake in 1943. The shape of H/V differed in the direction of horizontal motion near the fault line, and the subsurface structure model also differed between the areas near the fault line and other areas. The three-dimensional density structure obtained from the gravity anomaly shows a sharp drop in the south-falling bedrock in the vicinity of the fault line.