IDENTIFICATION OF PALU-KORO FAULT MECHANISM AND EARTHQUAKE HAZARD VULNERABILITY OF PALU AREA CENTRAL OF SULAWESI

Abstract

The identification of the Palu-Koro Fault and earthquake hazard vulnerability study has been conducted based on multi-criteria analysis which is a recent innovation zonation method of earthquake hazard vulnerable areas. The study method used is a merging scientific discipline of geology and geophysics. Field data collection (acquisition), processing, data analysis and modeling in the laboratory using several seismic software became the main framework in this study. Earthquake hazard vulnerability maps contain several criteria related to factors affecting the vulnerability level in the study area to the earthquakes hazard. Acquisition of geological investigation including fault-slip at 19 points and historical of 30 earthquakes data were used to verified fault type or earthquake focal mechanism. Microtremor measurements were conducted at 350 points throughout at the Palu area to analyze the vulnerability of earthquake hazard in the study area. The earthquake focal mechanism analysis shows the type of fault that predominantly controls through the Palu area and its surroundings controlled by strike-slip or horizontal fault mechanism. The micro-zonation analysis shows that the value of the resonant frequency (fo) in the range of 0.307 to 14.668, amplification factor (A) in the range of 1.297 to 8.946, the predominant period (Tg) in the range of 0.068 to 3.257, seismic vulnerability (Kg) in the range of 0.36 to 231, 97. Based on the vulnerability classification level and earthquake hazard shows that no area is safe. Particularly the impact caused by an earthquake due to the activity of Palu-Koro Fault.