Effect of Deformation of the Garsela Fault and Secondary Faults on Seismic Hazards, Case Study: Pasirwangi District, Garut Regency

The earthquake caused by the Garsela Fault significantly damaged the infrastructure and home of residents around Pasirwangi District. This fault is in Garut Regency, West Java and is one of the primary sources of earthquakes in Garut. This study aims to calculate rate of surface deformation and interpret its causes by analyzing InSAR data from 2017 to 2021. LiCSBAS, a Python-based time-series deformation analysis program, processed InSAR data to determine fault movement attributes and sources. Geological mapping, analysis of fault kinematics and dynamics determine the characteristics and fault movement. The results of time series analysis show that the rate of surface deformation in the Pasirwangi and its surrounding areas ranges from -45 mm/year to 35 mm/year. The movement mechanism of normal and right-normal slip faults causes the dominant surface subsidence. The difference in maximum ground movement acceleration between the north and south areas is caused by force moments which distributed at building points, affected by the differences in building density in the research area.