Interseismic deformation and strain-partitioning along the main Köpetdag fault, Turkmenistan, with Sentinel-1 InSAR time-series

SUMMARY The Main Köpetdag Fault (MKDF) is a predominantly right-lateral strike-slip fault that dissects the northern edge of mountains Turkmenistan and Iran. represents northernmost expression deformation from Arabia-Eurasia collision to east Caspian Sea, plays an important role facilitating motion South Basin (SCB). Despite kinematic significance MKDF, previous geodetic measurements slip-rate across have been highly variable, with recent geological supporting evidence for rapid fault. To resolve this ambiguity, we derive Sentinel-1 InSAR time-series in both ascending descending LOS (line-of-sight) measure interseismic MKDF. This implements processing strategy correction performance analysis tropospheric models GACOS (Generic Atmospheric Correction Online Service), which suggests 25–40 per cent under-estimation amplitude path delay region. Modelling rate fault-parallel MKDF combining constrains 9 ±2 mm/yr motion, along shallow locking depth ≈6 km. resolves delays greater than 1 geometries north aligned mapped frontal thrust scarps as uplift these thrusts estimates 4 shortening system. implies convergence measured GNSS within East Lowlands partitioned Revising Iran-Eurasia-SCB velocity triangle conjugate Shahroud zones representative SCB, moving at 10 direction 330○ ± 10○ relative Eurasia.