ANALISIS PEAK GROUND ACCELERATION (PGA) DAN B-VALUE DI WILAYAH MAMUJU, SULAWESI BARAT

Abstract

Sulawesi is a region with a high level of seismicity in Indonesia. This final project research discusses important parameters in earthquakes, namely Peak Ground Acceleration (PGA) and B-value which aims to determine the impact of earthquake damage in the research area: Mamuju Regency, West Sulawesi. In this study, the PGA value with the empirical equation was compared to the BMKG intensity map for the Mamuju earthquake in 2021. The PGA value using the Donovan method is 0.08 g (8% g) and that with the Boore method is 0.12 g (12% g). Based on the BMKG intensity map, PGA values range from 6.2 – 12% g. For the results of the value of b and a value in Mamuju Regency, namely 0.81 and 5.705 with a Mc value of 4.5. Based on this, it can be seen that a high b value is indicated by a low level of stress accumulation. The results of the earthquake occurrence frequency curve have a straight line with a-value and b- value, this indicates a low rock stress level. The West Sulawesi region has the potential for earthquakes with relatively high magnitudes.

Keywords: Peak Ground Acceleration, PGA, b-value, a-value, Earthquake, Sulawesi, Mamuju, Donovan, Boore, Intensity.