PS-INSAR TIME SERIES ANALYSIS USING SENTINEL-1A Data STACKS FOR SUBSIDENCE ESTIMATION IN VARAMIN PLAIN

In this paper, the PS-InSAR technique is applied to measure the land subsidence in the Varamin plain. This study is the first attempt in measuring surface deformation using PS-InSAR technique in this area. Varamin region is facing the problem of instability of terrain and structures against phenomenon like groundwater extraction. For southeast part of Varamin city, a time series of Sentinel-1A data stack, covering the time period from late 2014 to 2016, is analysed. We cross-validated the estimated deformation rates using another track of S-1A images and evaluated the trend of velocity in the time series analysis for the same area. For two analysis the results showed a significant land subsidence in northern and southern parts, located in the agricultural zones of the study area. Due to groundwater extraction in agricultural areas, the deformation has been seen in the study area. The maximum LOS displacement velocity of the area is estimated about 110 mm/year.