Depth‐Varying Friction on a Ramp‐Flat Fault Illuminated by ∼3‐Year InSAR Observations Following the 2017 Mw 7.3 Sarpol‐e Zahab Earthquake

We use interferometric synthetic aperture radar observations to investigate the fault geometry and afterslip evolution within 3 years after a mainshock. The postseismic favor ramp-flat structure in which flat angle should be lower than 10°. deformation is dominated by afterslip, while viscoelastic response negligible. A multisegment, stress-driven model (hereafter called SA-2 model) with depth-varying frictional properties better explains spatiotemporal of two-segment, SA-1 model). Although does not improve misfit significantly, this multisegment friction more physically plausible given mechanical stratigraphy region. Compared kinematic model, models variation tend underestimate early west, may indicate complex we expected. Both can resolve downdip although it could affected data noise resolution. transition depth sedimentary cover basement interface inferred ∼12 km seismogenic zone, coincides regional stratigraphic profile. Because coseismic rupture propagated along basement-involved slip activate frontal structures and/or shallower detachments cover, 2017 Sarpol-e Zahab earthquake have acted as typical event that contributed both thick- thin-skinned shortening Zagros seismic aseismic ways.