Subsidence monitoring by integration of time series analysis from different SAR images and impact assessment of stress and aquitard thickness on subsidence in Tehran, Iran

• Published in: Environmental earth sciences Vol. 80; no. 11; p. 418
• Main Authors: Yousefi, Roghayeh, Talebbeydokhti, Nasser
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2021; Springer Nature B.V
• Subjects: Aquifer storage; Aquifer systems; Aquifers; Biogeosciences; data collection; Datasets; Deformation; Earth and Environmental Science; Earth Sciences; Environmental Science and Engineering; Exploitation; Geochemistry; Geology; Groundwater; Hydrology/Water Resources; Illustrations; Integration; Interferometric synthetic aperture radar; Interferometry; Iran; Land subsidence; Model accuracy; Monitoring methods; Original Article; Radar; Radar imaging; SAR (radar); Strain; Stress-strain relationships; Subsidence; Synthetic aperture radar; Synthetic aperture radar interferometry; Terrestrial Pollution; Thickness; Time series; time series analysis; Tehran Iran; Iran; Integration; Subsidence; Sentinel-1A; ENVISAT ASAR; Stress–strain relationship; Subsidence-aquitard thickness relationship
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-021-09714-3

In recent decades, agricultural plains have been subject to significant subsidence in different parts of the world including Iran. Tehran plain is one of these parts exposed to land subsidence. In this paper, as the most effective method to monitor the subsidence, synthetic aperture radar interferometry (InSAR) makes use of two radar images to measure the ground surface deformation between two acquisitions. For this purpose, two different radar datasets including 16 ENVISAT ASAR images spanning from 2003 to 2008 and 12 Sentinel-1A images spanning from 2016 to 2017 were applied in InSAR small baseline subset (SBAS) time series analysis. Two distinct subsidence time series achieved from the two datasets were integrated using an appropriate model which was fitted to all data obtained from two time series results from 2003 to 2017 and verified running leveling measurements. The average value of the root mean square errors (RMSEs) calculated between the model and the achieved time series at all pixels is 0.02 m which is an illustration of the accuracy of the proposed model to join the two deformation time series results. Furthermore, the integration results were additionally used to discover the storage properties of the aquifer system by stress–strain relationship and the effect of aquitard thickness on subsidence of Tehran plain by subsidence-aquitard thickness (fine-grained interbed) relationship, respectively. The stress–strain relationship shows a low correlation between subsidence and groundwater exploitation where a direct relationship between subsidence and aquitard thickness is clearly obvious.