Perpustakaan Digital ITB

Probabilistic seismic hazard analysis (PSHA) for Sumatra Island considering 3-dimensional seismic source zones is presented in this paper. In this analysis, seismic source characterization of both subduction sources in the west and shallow crustal faults of Sumatra Fault Zones (SFZ) is investigated. The analysis presents probability level of 10% and 2% probability of exceedance in 50 years. The PSHA was conducted at a grid spacing of 0.5 degree, resulted in each point with corresponding uniform hazard spectra for each hazard level. Seismic hazard maps produced from the PSHA consist of two probability of exceedance level, each with three spectral values, that is for PBA, short period (T=0.2 sec), and long period (T=1.0 sec), respectively. Seismic hazard map for 10% probability of exceedance in 50 years resulted from this study shows some noticeable differences compared to the current Indonesian seismic hazard map, particularly in the area along the SFZ. De-aggregation analysis suggest controlling earthquakes and target spectra for seismic input motion in site-response analyses of various site-class. The methodology of probabilistic seismic hazard mapping and seismic ground motion analysis that has been developed for Sumatra Island could be extended further for other islands for input to the current seismic hazard map of Indonesia.