Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 51 6 2020 02 20 Mashhad Subsidence Monitoring by Interferometric Synthetic Aperture Radar Technique Mashhad Subsidence Monitoring by Interferometric Synthetic Aperture Radar Technique 1187 1204 3019 10.22060/ceej.2018.14300.5617 FA Mohammad Khorrami Department of Civil Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran Saeed Abrishami Department of Civil Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran 0000-0002-4627-5531 Yasser Maghsoudi Department of Photogrammetry and Remote Sensing, Faculty of Geodesy and Geomatics Engineering, K. N. Toosi University of Technology, Tehran, Iran Journal Article 2018 04 09 Deep groundwater withdrawal in Mashhad, one of the largest municipalities in Iran, caused severe land subsidence. Land subsidence in this area can be destructive for urban infrastructures and can create serious environmental issues and structural damages. The main aim of this research is to precisely determine the vertical ground deformations in Mashhad to evaluate and compare the current situation with the previous reports on this area. For this purpose, we have applied Persistent Scatterer Interferometric Synthetic Aperture Radar technique to complement previous works by using more accurate data and procedure in the interested urban area. Furthermore, we considered geotechnical properties which were not focused in the previous studies. For this purpose, 69 descending and ascending C-band radar images, provided by relatively high-resolution Sentinel-1A satellite, were used to estimate the deformation-trend. The method was applied to the images from October, 2014, to February, 2017. The assessment procedure demonstrated a high-rate of subsidence in northwest of Mashhad with the significant deformation of 140 mm/year. The outputs were validated using in-situ measurements data and hydraulic head variations respecting piezometric data extracted from groundwater wells. Subsequently, the geotechnical properties of the chosen area were considered to interpret the results. The results of this study illustrated that the land subsidence in the case study is brutally continuous in most areas and there is no sign of decrease in the amount of deformation rate. Deep groundwater withdrawal in Mashhad, one of the largest municipalities in Iran, caused severe land subsidence. Land subsidence in this area can be destructive for urban infrastructures and can create serious environmental issues and structural damages. The main aim of this research is to precisely determine the vertical ground deformations in Mashhad to evaluate and compare the current situation with the previous reports on this area. For this purpose, we have applied Persistent Scatterer Interferometric Synthetic Aperture Radar technique to complement previous works by using more accurate data and procedure in the interested urban area. Furthermore, we considered geotechnical properties which were not focused in the previous studies. For this purpose, 69 descending and ascending C-band radar images, provided by relatively high-resolution Sentinel-1A satellite, were used to estimate the deformation-trend. The method was applied to the images from October, 2014, to February, 2017. The assessment procedure demonstrated a high-rate of subsidence in northwest of Mashhad with the significant deformation of 140 mm/year. The outputs were validated using in-situ measurements data and hydraulic head variations respecting piezometric data extracted from groundwater wells. Subsequently, the geotechnical properties of the chosen area were considered to interpret the results. The results of this study illustrated that the land subsidence in the case study is brutally continuous in most areas and there is no sign of decrease in the amount of deformation rate. https://ceej.aut.ac.ir/article_3019_a74c3bae3e13616104c1b25f9da1f11f.pdf