Evaluation of the strong motion at the Aratozawa site induced by the 2008 Iwate-Miyagi Nairiku Earthquake based on empirical site amplification and phase effects

Abstract

Many landslides occurred in a large area during the 2008 Iwate-Miyagi Nairiku Earthquake. The greatest landslide and disaster on record occurred in Aratozawa near the seismic fault. Therefore, evaluation by high accuracy of the strong seismic motion at the Aratozawa landslide is very important to analyze the landslide mechanism. Hence, the evaluation of seismic response characteristics at this site is necessary. In this study, seismic waveform at the Aratozawa landslide was estimated based on empirical site amplification and phase effects. Site amplification characteristics at the Aratozawa landslide were evaluated based on the aftershock observation records. Moreover, a characterized source model for strong ground motion prediction was constructed based on the results of waveform inversion for this earthquake.