بررسي و پايش فرونشست نامتقارن با استفاده از تكنيك تداخل سنجي راداري (مطالعه موردي: منطقه برخوار اصفهان)

Investigating an‎d Monitoring Asymmetric Subsidence Using Interferometry Technique (Case Study: Borkhar Region of Isfahan)

مهندسي نقشه برداري

Lan‎d subsidence as a todayʹs significant geohazard, presenting substantial challenges to human activities an‎d infrastructure. Synthetic Aperture Radar (SAR) interferometry serves as an effective tool for monitoring this phenomenon. This dissertation examines heterogeneous subsidence through the application of the gradient tensor. The study area is Borkhar County, located in Isfahan Province, Iran, where subsidence was monitored using time-series SAR interferometry with short-baseline datasets. The temporal scope of the analysis extends from November 11, 2015, to July 10, 2024. A total of 31,926,267 pixels, encompassing 975 interferograms, were processed an‎d analyzed. The findings indicate the mean displacement velocity in the satellite’s line-of-sight direction ranging from 0 to -52.1 mm/year in Borkhar County. The calculated subsidence ranged from 0 to 66.3 mm, with cumulative subsidence varying between 0 an‎d 721.678 mm. Application of the gradient tensor yielded values of 0 to 0.004 for cumulative subsidence an‎d 0 to 0.00042 for average velocity. The accuracy of these results was corroborated by comparison with data from the German Research Centre, achieving a correlation coefficient of 0.9857. Additionally, a correlation of 0.74 was determined between the InSAR time series an‎d piezometric well data provided by the Isfahan Regional Water Authority for Borkhar County. Using a linear regression algorithm, critical zones exhibiting distinct linear behavior were identified. The final analysis revealed correlation coefficients of 0.6779 for the cumulative subsidence gradient an‎d 0.6606 for the mean velocity gradient.

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