Integrating new GMPE and Seismic b-value for comprehensive hazard analysis in Central, West, and South Sulawesi, Indonesia

Abstract

Detailed seismic hazard analysis is a critical component in identifying regions with elevated earthquake risk. Consequently, the estimation of seismotectonic parameters (b-value) and the development of ground motion prediction equations (GMPEs) that capture the local characteristics of an area are essential for assessing peak ground acceleration (PGA) in earthquake hazard analysis. The GMPE model is typically constructed using a least squares inversion linear regression approach, while the b-value is estimated through the maximum likelihood method. The findings of this study indicate that the PGA values in the research area range from 0.77 to 8.36 gal, and the b-values fall within the interval of 0.11 to 1.86. The areas with high PGA values are observed in the vicinity of active faults, which can facilitate the occurrence of large earthquakes, as well as regions with weaker geological conditions. Furthermore, the low b-value results suggest the potential for stress accumulation in certain areas, which may lead to the occurrence of moderate to large magnitude earthquakes.