Peak Ground Acceleration of East Malaysia Based on a Proposed Ground Motion Prediction Equation

Seismic hazard analysis is generally carried out for a place at active seismicity region. Such analysis is rarely performed for low-to-moderate region as in East Malaysia. The seismic hazard analysis requires estimation of ground motion intensity where the process needs to use a compatible ground motion prediction equation or GMPE. The analysis provides a peak ground acceleration (PGA) estimates in a function of earthquake magnitude and distance. In this study, the characteristics of low-to-moderate databases were used and derived by regression analysis in terms of horizontal PGA. The appropriate GMPE design for East Malaysia is based on ground motions recorded compiled from shallow to deep strike slip earthquakes. Furthermore, earthquake data is based on actual data recorded at a broad range of magnitude levels within a wide range of distances. The new equation is used to predict the PGA value throughout East Malaysia by probabilistic seismic hazard analysis (PSHA). PSHA is a method to analyse seismic hazard assessment using probability concept by considering the uncertainties of the size, location and rate of occurrence of earthquake and the variation of ground motion characteristics. With collection of more earthquake databases, GMPE have become more reliable. The GMPE of peak ground acceleration for low-to-moderate earthquake at long distance was found to be logarithmically distributed. The equation provides ease in both implementation and interpretation of physical parameters with comparable standard deviation.