Monitoring ground subsidence in coastal area with advanced InSAR techniques: Shangyu District case study

In this study, we obtain ground subsidence result in Shangyu District, a coastal city of China, using DS-InSAR approach with 24 COSMO-SkyMed images. The causes of ground subsidence were analyzed with geology data and field investigation preliminary. The result indicates that urban construction, groundwater overpumping, compaction of fill materials and overloads induced by constructions in land reclamation zone were responsible for ground subsidence. The InSAR result was validated with levelling measurements, achieving an average error and a standard deviation with-0.8 mm/year and ±4.9 mm/year which could reach the standard of urban subsidence monitoring.