Document Type : Original Research Paper


Department of Structure and Earthquake, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran


The Doruneh fault system with more than 700 km length, after the main Zagros fault, is known as the largest fault in Iran. In this research, this fault system is divided into 3 main parts because the mechanisms of its different parts are different. The western part is reported to have a left lateral strike-slip mechanism with a reverse component, the middle part is a left lateral strike-slip mechanism, and the eastern part is reported to have a reverse mechanism. In this study, seismicity parameters and their temporal and spatial changes along this fault system are analyzed using seismic data collected from 1980 to 2023 and based on the maximum likelihood method. In this regard, the temporal changes of b-value shows two significant drops, which indicate two relatively strong Torbat-e Heydarieh earthquakes in 2010 and the Fariman earthquake in 2017. Despite the fact that the scientific community is not yet able to accurately predict earthquakes, according to the studied method and with the continuous monitoring and analysis of various earthquake parameters, especially b-value, it is not far from expected to predict the occurrence of possible earthquakes in the future.


Main Subjects

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