社団法人　物理探査学会
第130回(平成26年度春季)学術講演会

講演要旨(和文) 講演要旨(英文) The objective of this study is to obtain a 2D shallow soil profile at the vicinity of the Tsukidate strong motion station (MYG004), to provide basic material for the understanding of the high accelerations during the 2011 Tohoku earthquake. We conducted a seismic refraction survey westward the station, and used a full waveform inversion of the acquired seismic data to retrieve a 2D shallow soil profile. The inverted 2D soil model underlines a clear lateral S-wave velocity variation in the surface layer. Comparisons with results of the microtremor measurements using array and horizontal-to-vertical ratio conducted along the seismic survey line show significant similarity with the lateral velocity variation revealed by our 2D inversion. We also examined the effect of this velocity inhomogenity on the soil response during an earthquake, and found out that it can have an important role on amplifying the high frequencies content.