An Overview of the Seismic Activity in Behbahan City, Southwest Iran

This study examines the seismic activity and hazards in Behbahan City, southwestern Iran, situated within the seismically active Zagros Fold-Thrust Belt. Historical earthquakes, including devastating events in ۱۰۵۲ and ۱۰۸۵ AD, highlight the region's vulnerability. The area is characterized by ongoing crustal shortening due to the Arabian-Eurasian plate convergence, with several active faults, such as the Behbahan, Aghajari, and Arjan faults, posing significant threats. Analysis of regional seismotectonic frameworks reveals that Behbahan is consistently classified as a high-seismic-hazard zone, with potential for earthquakes exceeding magnitude ۷.۰. Our fault analysis identifies the Behbahan Fault as posing the highest immediate risk, with an estimated moment magnitude of ۷.۳۵ at a distance of ۸.۴ km from the city. The study recommends microzonation studies, retrofitting of vulnerable structures (especially unreinforced masonry buildings), implementation of early-warning systems, and the development of revised peak ground acceleration (PGA) maps. Multi-disciplinary research integrating InSAR, paleoseismology, and geotechnical data is crucial for refining hazard assessments and mitigating future earthquake impacts in this historically significant and densely populated region.

کلیدواژه ها:

Seismic hazard ، Seismic risk ، Active faults ، maximum magnitude of earthquakes