Stochastic Strong-Motion Simulation in Borehole and on Surface for the 2011 M-w 9.0 Tohoku-Oki Megathrust Earthquake Considering P, SV, and SH Amplification Transfer Functions

摘要

The 2011 Tohoku-Oki megathrust earthquake and its aftershocks were well recorded by the KiK-net network in accelerographs placed inside boreholes and on the surface. These data allow comparing strong-motion records with synthetic acceleration time histories for this large magnitude earthquake that caused extensive damage in Japan. Generating synthetic accelerograms at high frequencies can be approached using different techniques. We use the stochastic method to simulate horizontal and vertical strong-motion accelerograms in hard-rock boreholes; additionally, we incorporate P, SV, and SH soil amplification transfer functions to generate surface accelerograms. We reproduce the three components of the strong motion for 18 stations of the Mw 9.0 mainshock event; additionally, we simulated 8 stations for an Mw 6.9 aftershock. Our simulated acceleration time histories show similarity in time and frequency with the acceleration records for the period band between 0.05 and 1 s.