Land Subsidence Assessment due to Groundwater Exploration by using Radar Interferometry Technique, Case Study: Fasa Plain.

 Interferometric Synthetic Aperture Radar (InSAR) is a powerful instrument in estimating subsidence with millimeter accuracy. This article uses Sentinel 1A satellite data from 2016 to 2020 to monitor subsidence in Fasa plain. The results of radar interference studies showed that 24 cm subsidence occurred in the study area during the statistical period. In order to find the cause of subsidence, information of piezo metric wells in the area was collected and their changes during the period 1372-1399 were studied. According to the results, the groundwater level in areas with land subsidence has been associated with a decline. Especially in the villages of Dastjeh, Sahravard and Ghazi Kouchak, which have the highest rate of groundwater level drop and are in the zone of high subsidence risk. The lands of the region mostly include gardens and irrigated cultivation. In this regard, it can be said that one of the main reasons for land subsidence in the study area is the uncontrolled abstraction of groundwater resources