Mapping of PGA Value Using PSA Method in West Halmahera Nort Maluku

Abstract

The earthquake that occurred in the West Halmahera region was very detrimental, even though the human casualties were not very significant. But it will affect the stability and capacity of a region in terms of regional development. The mapping of earthquake-prone areas is carried out by a probabilistic seismic hazard analysis (PSHA) method to analyze soil movement parameters, namely Peak Ground Acceleration so that it can determine earthquake-prone areas in West Halmahera. The results of seismic hazard analysis show that the West Halmahera area is an area that is relatively prone to earthquake hazards because it is still strongly influenced by subduction (megathrust) earthquakes from the Philippine plate, Maluku sea and Sangihe. This is indicated by the value of earthquake acceleration on the Peak Ground Acceleration for the 500 year return period of around 0.38 - 3.69 g and 0.30 - 3.69 g for the 2500 year return period.

Earthquake Disaster Risk Analysis in South Morotai Tourism Area

“…Based on tectonic activity, it can be concluded that Morotai Island has a high potential for earthquake hazard. This can also be seen from the earthquake hazard map for Morotai Island that has been carried out by (Ningrum, et al, 2020) and is shown in Figure 5. The highest Peak Ground Acceleration (PGA) value for Morotai Island is 3.8 gal, this is influenced by by the source of the subduction earthquake from the Philippine plate, the Maluku Sea and the Sangihe Sea.…”

“…Data needs for hazard studies are taken from data for preparing hazard studies such as earthquake hazard maps sourced from the North Maluku Earthquake Hazard Map made by Ningrum, et al, 2020 and the 2017 Indonesia Earthquake Source and Hazard Map made by the National Earthquake Study Center. (Pusgen).…”