A note of ground motion interpretation and site response analysis during the 2007 Bengkulu–Mentawai earthquakes, Indonesia

Abstract

This paper presents the interpretation of ground motions and comparison of site response analysis due to the 2007 Bengkulu–Mentawai earthquakes in Mukomuko regency, Bengkulu Province, Indonesia. Mukomuko regency was reported as the most impacted area during the earthquakes. The recorded ground motions of the Bengkulu–Mentawai earthquakes were analysed to obtain the interpretation of ground motions. Furthermore, the site response analysis to the sites in Mukomuko regency was performed to observe the spectral acceleration. The results showed that the first aftershock tends to have more played the key role in yielding the damage in Mukomuko regency. It was shown by the high level of Modified Mercalli Intensity (MMI) and the high ground motion parameters resulted by the first aftershock. The comparison of spectral acceleration showed that spectral acceleration of first aftershock is critical at a short period. The result also showed that the propagated seismic waves could amplify at ground surface. In general, the results of this study could provide a better understanding of earthquake impact in Mukomuko regency, Indonesia.