Testing the rigid block rotation model in Central-Eastern Iran under active tectonic regime

Central-Eastern Iran (CEI) is a strike-slip zone comprising two sets of right-lateral fault zones arranged in NNW-SSE and N-S directions. This configuration provides an opportunity to test the block rotation model within a natural strike-slip fault zone. Therefore, in this study, we apply a fault-bounded block rotation model, developed for strike-slip zones, to evaluate the compatibility of this model with the kinematics of the CEI since the Neogene. The cumulative offsets and slip rates along the block-bounding faults predicted by this model are consistent with those estimated from geological, geomorphological, and geodetic studies, at least within their uncertainties. The results show that the CEI accommodates Arabian-Eurasian convergence primarily through strike-slip faulting. Furthermore, rotation of fault-bounded blocks in the CEI can accommodate part of the convergence, while also exerting a significant influence on the structural geometry and seismicity of the region. Integrating the results of the fault-bonded block rotation model with stress analysis shows that both the orientation of the maximum horizontal compressive stress (SHmax) relative to the fault strike and the rotation of fault-bounded blocks control the sense of shear on faults in CEI. This study may help explain how large strike-slip faults can control the structural framework of a region through rotation of fault-bounded blocks.