Strong Motion Estimation at Okushiri Port Landslide induced by the 1993 Southwest Hokkaido Earthquake based on the Empirical Site Amplification and Phase Effects

Abstract

Some landslides occurred in the near-source region of the 1993 Southwest Hokkaido Earthquake. A large scale landslide and disaster occurred close to Okushiri Port. Therefore, to clarify the landslide mechanism, it is necessary to estimate strong motions at the landslide with sufficient accuracy, taking into account local site effects. In this study, seismic waveform at the landslide was estimated based on the characterized source model considering site amplification and phase effects. The site effects at Okushiri Town Office was used for the site effects at the landslide based on similarity of microtremor H/V spectra.