Decadal-scale analysis of Land Subsidence in Golestan province, Iran, Using SBAS-InSAR

Golestan Province in Iran is famous for its extensive agricultural production, where groundwater serves as the main source of irrigation. Continuous groundwater extraction in the region has led to declining water levels, resulting in widespread land subsidence, reducing groundwater storage capabilities and posing risks to infrastructure. To assess the impact of land subsidence in the area on the environment and infrastructure, we employ Interferometric Synthetic Aperture Radar (InSAR) technology. We use the Small Baseline Subset (SBAS) InSAR technique integrated within MintPy software to analyze the overall land subsidence in Golestan Province, utilizing data from various SAR sensors, including Sentinel-1, ALOS, Envisat, and ERS. Additionally, we apply the Persistent Scatterer Interferometry (PSI) method integrated into SARvey software to estimate localized subsidence affecting infrastructure. We analyze Sentinel-1 data from 2014 to 2025 in both ascending and descending tracks to obtain the current rates of subsidence. Furthermore, we use ALOS, Envisat, and ERS data to estimate the historical rates of subsidence in the region. The results show that long-term subsidence is predominant in the Gorgan Plain, characterized by an east-west orientation and a maximum subsidence rate > 10  cm/year from 2014 to 2025. Results are analyzed to separate the effect of elastic from inelastic deformation and assess changes in the storativity of the aquifers over the last 3 decades.