Modified of Ground Motion Prediction Equation in Indonesia, Case Study: South and South-East of Sulawesi at 2011-2015

摘要

Within the last decade, advances on empirical formula to determine ground acceleration is strongly involved in order to undertake seismic hazard analysis. We need to provide a means of estimating the ground shaking from an earthquake given its earthquake source type, ray-path, and local site condition called Ground Motion Prediction Equations (GMPEs). However, this study is rarely done in South and South-East of Sulawesi. This study aims to determine the GMPEs coefficient using selected 481 record of ground motion database by 18 accelerometer at 2011-2015. Local site condition of station is classified by dominant period and the type of earthquake is segregate according to tectonic regime that is shallow crustal, interface and intraslab. We made statistical regression analysis to find the relation between attenuation and distance. The result shows that attenuation relation of low value ground acceleration to increasing of distance has peak ground acceleration much lower, compare to early equation that fitted to peak ground acceleration observation in South and South-East of Sulawesi. It also show the effect of magnitude, focal depth, source distance, and local site can affected PGA predicted. This study plays vital role to understand the characteristic of ground motion attenuation.