A comprehensive analysis of the Sistan Suture Zone: tectonic implications and stress dynamics

چکیده مقاله

The Sistan Suture Zone (SSZ) in eastern Iran is a significant tectonic boundary separating the Helmand Block from the Central-East Iranian Microcontinent (CEIM). This study provides a comprehensive review of its tectonic framework by integrating structural, geodynamic, and seismic data. The aim is to clarify stress distribution, fault dynamics, and deformation patterns in the region. The SSZ is primarily characterized by N-S trending right-lateral strike-slip faults, which exhibit no rotational deformation and facilitate differential motion between adjacent tectonic blocks. In contrast, the Dorouneh Fault System shows left-lateral motion with clockwise rotation, reflecting the region's tectonic complexity. The Qasr-e Qand Fault is identified as a crucial boundary marking the transition to the Makran Subduction Zone, where compressional forces dominate, and a steep lithospheric dip is observed. Additionally, the Lut Block experiences counterclockwise rotation and heightened fault activity under regional stress. Quantitative analyses reveal variations in fault slip rates, with active faults effectively accommodating strain across the zone. This synthesis underscores the SSZ's critical role in regional tectonic processes, linking surface deformation to deeper subduction mechanisms. The findings enhance our understanding of the SSZ's evolution, its implications for seismic hazard assessment, and its broader geodynamic connections to the Makran Subduction Zone and adjacent tectonic systems