Integrated InSAR Assessment of Surface Strain, Differential

Land subsidence in urban environments is governed by both cumulative displacement and its spatial and temporal 10 organization. This study integrates multi-geometry Sentinel-1 interferometry and contemporaneous GNSS 11 measurements for Isfahan, Iran, in a unified analysis of horizontal surface strain, differential settlement, settlement-12 surface curvature, subsidence-bowl morphology and spatiotemporal dynamics. The analysis covers the five-year period 13 from 1 January 2020 through 31 December 2024, using ascending and descending Sentinel-1 observations. Three-14 component displacement estimates provide the kinematic foundation of the analysis, while station displacements over 15 the same observation period furnish independent component-wise validation. Directional strain operators, finite-16 baseline distortion, second-order derivatives and geometric shape descriptors are defined in metric coordinates, 17 together with temporal decomposition into secular and periodic terms. Contemporaneous GNSS observations at four 18 stations provide component-wise geodetic validation. The station-level cross-check identifies displacement differences 19 of 10–30 mm between GNSS and InSAR, as confirmed in the study records. The integrated framework connects the 20 magnitude, localization, orientation, shape and evolution of ground deformation and supports spatially explicit 21 assessment of differential-settlement patterns in the Isfahan urban area. 22