Assessing Three-Dimensional Displacement in the Low Latitude Area from Multi-Geometry Sentinel-1 InSAR: Case Study Palu City

Interferometry Synthetic Aperture Radar (InSAR) technology has revolutionized displacement monitoring. Still, accurately discerning the North-South component in low-latitude regions is a challenge. This research investigates the significance of horizontal movement for accurate 3D displacements in Indonesia, with Palu City as a focus. Utilizing a time-series 3D decomposition with the Least Square Adjustment method, findings reveal urban areas experiencing vertical land subsidence, and uplift in active hill regions, with predominant northward horizontal displacement. Comparison with GNSS measurements demonstrates the accuracy of the 3D displacement model. This study underscores the necessity of horizontal movement consideration in 3D displacement monitoring in low-latitude areas, offering insights for geohazard analysis, disaster readiness, and infrastructure blueprinting.