Mapping of Areas Affected by the Eruption of Mount Marapi in West Sumatra Using the Differential Interferometric Synthetic Aperture Radar (DInSAR) Method

Satellite-based monitoring provides spatial information on surface changes in active volcanic regions, yet displacement patterns around Mount Marapi, West Sumatra, spanning the December 2023 eruption require further examination. This study mapped and analyzed surface displacement using differential interferometric synthetic aperture radar (DInSAR). A quantitative descriptive approach with a geospatial case study design employed two Sentinel-1A images acquired on November 28, 2023, and February 8, 2024. Processing in the Sentinel Application Platform (SNAP) included image coregistration, interferogram generation, phase filtering, phase unwrapping, and terrain correction. The results indicated spatially varying line-of-sight (LOS) displacement ranging from −0.006 to +0.460 m. Higher positive values, approximately +0.228 to +0.460 m, were concentrated around Pasie Laweh and Mount Marapi, whereas surrounding areas exhibited lower values. These estimates represent cumulative LOS changes over the acquisition interval and do not establish vertical deformation or a direct causal relationship with the eruption. The findings illustrate the potential of DInSAR to support volcanic surface monitoring and contribute spatial information for further hazard assessment. Additional satellite observations and ground-based validation are needed to strengthen displacement interpretation.