Co-seismic slip of the 18 April 2021 Mw 5.9 Genaveh earthquake in the South Dezful Embayment of Zagros (Iran) and its aftershock sequence


  • Mohammadreza Jamalreyhani GFZ German Research Center for Geosciences, Potsdam, Germany
  • Léa Pousse-Beltran University Grenoble Alpes, University Savoie Mont Blanc, CNRS, IRD, UGE, ISTerre, Grenoble, France.
  • MirAli Hassanzadeh Department of Earth Sciences, Institute for Advanced Studies in Basic Sciences, Zanjan, Iran
  • Samineh Sadat Arabi SRBIAU Sience & Research Branch of Islamic Azad University
  • Eric A. Bergman Global Seismological Services, Golden, CO, USA
  • Aref Shamszadeh Department of Earth Sciences, College of Sciences, Shiraz University, Shiraz, Iran
  • Shiva Arvin Department of Earth Sciences, Institute for Advanced Studies in Basic Sciences, Zanjan, Iran.
  • Niusha Fariborzi Department of Earth Sciences, Institute for Advanced Studies in Basic Sciences, Zanjan, Iran.
  • Ali Songhori Institute of Geophysics, University of Tehran, Tehran, Iran



The 18 April 2021 Mw 5.9 Genaveh earthquake, slip distribution, Zagros, InSAR, Gulkhari anticline, Dezful embayment, moment tensor inversion, relocation


On 2021 April 18, an Mw 5.9 earthquake struck the Genaveh region in the south Dezful embayment of the Zagros, Iran. Here, we investigate the active tectonics of the region, the geometry and slip distribution of the causative fault plane, and its aftershock behavior. We applied a combination of different geodetic and seismological methods (slip distribution inversion of the mainshock using Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR), relocation, and moment tensor inversion of aftershocks and background seismicity of the region). Co-seismic InSAR modeling shows that the slip is confined to the sedimentary cover at depths of 4-7 km with a maximum slip of 1 m and highlights the influence of lithology in the rupture propagation. Moment tensors and centroid depths of aftershocks down to Mw 4 show that the distributed aftershocks sequence is dominated by reverse faulting at centroid depths of 4-10 km. The causative fault is compatible and parallel to the trend of the Gulkhari anticline and the coseismic uplift of the Genaveh earthquake implies that the growth of this particular fold is linked to the fault(s). However, still, due to the absence of surface rupture, the clear relationship between buried faulting and surface folding remains unclear.

Author Biography

Mohammadreza Jamalreyhani, GFZ German Research Center for Geosciences, Potsdam, Germany

Second Affiliation: University of Tehran Institute of Geophysics


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How to Cite

Jamalreyhani, M., Pousse-Beltran, L., Hassanzadeh, M., Sadat Arabi, S., A. Bergman, E., Shamszadeh, A., Arvin, S., Fariborzi, N., & Songhori, A. (2023). Co-seismic slip of the 18 April 2021 Mw 5.9 Genaveh earthquake in the South Dezful Embayment of Zagros (Iran) and its aftershock sequence. Seismica, 2(1).