Space-Time Evolutions of Land Subsidence in the Choushui River Alluvial Fan (Taiwan) from Multiple-Sensor Observations

Land subsidence is a significant problem around the world that can increase risk of flooding, damage to infrastructure, and economic loss. Hence, continual monitoring important for early detection, mechanism understanding, countermeasure implementation, deformation prediction. In this study, we used multiple-sensor observations from Continuous Global Positioning System (CGPS), small baseline subset (SBAS) algorithm, interferometric synthetic-aperture radar (InSAR), precise leveling, multi-layer compaction wells (MLCWs), groundwater observation (GWs) show spatial temporal details land in Choushui River alluvial fan (CRAF), Taiwan, 1993 2019. The results showed has occurred along coastal areas CRAF, most inland have also experienced higher rates (>30 mm/yr). analysis Taiwan High Speed Rail (THSR) revealed newly formed center between Tuku Yuanchang Townships Yunlin, with high ranging 30 70 mm/yr. We propose map showing, first time, distribution deep compactions occurring below 300 m depth CRAF.