Extracting 3-dimensional co-seismic displacement using InSAR techniques

Synthetic-aperture radar (SAR) has emerged as a dependable data source across various disciplines, particularly in geophysics. Its utility extends to applications such as fault zones assessment, surface rupture extent estimation, and evaluation of potential infrastructure damage. A key advantage of SAR data in remote sensing for seismology lies in its reliability, as it operates independently of the day/night cycle and weather conditions within the designated area of interest. This characteristic enhances its efficacy in providing consistent and uninterrupted observations for seismic monitoring and analysis. This study proposes a slightly modified methodology for extracting three-dimensional movements of the terrain by leveraging ascending and descending synthetic-aperture radar (SAR) images acquired both pre- and post-event. The approach aims to contribute to a more comprehensive understanding of geophysical dynamics by analyzing SAR data in both orbital configurations, providing insights into the spatial and temporal aspects of co-seismic deformation. 
A seismic event investigation was conducted, focusing on the magnitude 6.9 earthquake that occurred in Indonesia on August 5, 2018. This seismic event was attributed to a shallow thrust fault located on or near the Flores Back Arc Thrust. The study utilized Sentinel-1 data for Differential Interferometric Synthetic Aperture Radar (DInSAR) processing and phase unwrapping, employing conventional procedures. The three-dimensional displacement extraction method was applied to the processed data, and the resulting image underwent a comprehensive analysis. The findings reveal a maximum displacement of 0.35 meters in the north-south direction, 0.125 meters in the east-west direction, and an uplift of approximately 0.68 meters.