Earthquake Potential Hazard Analysis of Palembang City, Sumatra Island

Abstract

Most of the destructive earthquakes in Sumatra are dominated by thrust mechanisms that occur due to the process of subduction and some earthquakes with strike-slip fault sources such as the Sumatra fault and northwestern Sumatra. Subduction zones along western Sumatra and Sumatran fault zones are active seismic sources of earthquake events. The seismotectonics of South Sumatra can be affected by earthquakes triggered by these seismic sources. In this study, an estimation and analysis of the potential for earthquake hazard curves were carried out in Palembang City due to the influence of subduction zone sources, strike-slip faults, and intermediate to deep earthquake sources. The algorithm of the seismicity smoothing was applied to estimate the seismicity rate for megathrust sources, active faults, and intermediate to deep earthquake sources. The smoothing algorithm is applied to estimate the seismicity rate for megathrust sources, active faults, and intermediate to deep earthquake sources. The earthquake hazard potential curve results showed that the estimated Peak Ground Acceleration (PGA) in the subduction earthquake sources bedrock was greater than the estimated ground shaking due to strike slip fault sources and intermediate to deep earthquake source. To understand better the potential ground shaking, the evaluation of PGA at the surface was then estimated by including the amplification factor. The amplification factor is calculated using the Horizontal-Vertical Spectral Ratio (HVSR) method. Based on the PGA estimated at the surface of 10% probability exceedance level during 50 years, the Palembang City has a potential shaking of around 35 gal, which is likely to be caused by a megathrust earthquake source.

Seismic Hazard Function Mapping Using Estimated Horizontal Crustal Strain Off West Coast Northern Sumatra

“…This study's motivation was to perform a probabilistic seismic hazard analysis using the source area's surface displacement data off the west coast of northern Sumatra on March 28, 2005. Based on the previous study by Triyoso et al (2021), the Sumatran Fault's impact on the seismic hazard analysis in the vicinity of the major subduction event could be neglected. Considering the availability of the recorded pre-and co-seismic GPS data in the (Frankel, 1995) weighted by normalizing the estimated seismic moment rate model (C).…”

“…The study area is around the subduction zone of M w 8.6. Based on the previous results (Triyoso et al, 2021), the Sumatran Fault's impact could be neglected.…”

Fractal Dimension Analysis and Earthquake Repeated Period Estimation in the Southern Part of Sumatra Subduction Zone (Bengkulu-Lampung-Sunda Segment)

“…This is evidenced by the large number of earthquake damage data in several regions in Indonesia. Most of the destructive earthquakes in Sumatra are dominated by earthquakes with thrust mechanisms that occur due to the subduc-tion process and strike-slip mechanisms, such as the Sumatra Subduction Zone (SSZ) and Sumatra Fault Zone (SFZ) (Triyoso et al, 2021).…”

Mapping of Peak Ground Acceleration (PGA) Values using the Donovan Model for Sumatran

“…Still in disaster mitigation efforts for Bengkulu Dewi Susiloningtyas [8] made a spatial pattern of earthquake-prone areas by calculating the PGA value in 2010 -2018 and determining the tsunami inundation area based on wave heights of 5 m, 20 m, and 25 m. It was found that the high risk area is on the southern coast of Bengkulu in the Kampung Melayu sub-district with an estimated affected area of 653.69 Ha. The results of research by Wahyu Triyoso and Aris Suwondo [9] who evaluated PGA by including an amplification factor calculated using the Horizontal-Vertical Spectral Ratio (HVSR) method with a subduction earthquake source, which is greater than the estimated ground shaking due to a shear fault source and a medium to deep earthquake source. for the city of Palembang, gives the result that the city of Palembang has a potential shock of about 35 gal, which is probably caused by the source of the megathrust earthquake.…”