Analysis of the Seismicity Parameters and Strong Ground Movement in Sarpol-e Zahab and its Related Crises

The occurrence of natural disasters can be considered one of the most important concerns of human life, especially for the people of developing countries. The existence of natural disasters in Iran has made Iran one of the top 10 countries in the world in terms of disasters. Analysis of seismic data shows that almost every 5 years, on average, an earthquake with a magnitude of 7 (such as the Saravan and Sarpol-e-Zahab -Kermanshah earthquakes) occurs in Iran and has serious effects on human society. In this study, the parameters of strong ground motion in the Sarpol-e-Zahab area have been analyzed with a special focus on its crisis.

In order to evaluate the return period of the earthquake in this fault system, two preliminary relationships of Gutenberg-Richter and the final distribution of the Kijku-Sellovel method have been used. In order to study seismicity and seismic hazard analysis, after studying the geology of the study area, the tectonics and seismicity of the region were studied. After that, a tectonic seismic model was prepared from this zone to better determine the nature of seismicity. Then, the seismic source database of the study area was defined and entered into EZ-frisk software for further analysis.

The magnitude of the earthquakes based on the Gutenberg-Richter and Kijku-Sellovel methods has shown that the magnitude of the earthquake in the 475-year return period is 6.9Ms and 7.0Ms, subsequently. A magnitude of more than 7.8 is not expected in this region based on the Gutenberg-Richter method. On the other hand, the values of acceleration on the side where the fault slope is (northeast of the fault), have higher values than on the opposite side.In addition, the maximum acceleration of the earthquake in the position of the mountain frontal fault is estimated 0.75 gal.

Therefore , considering considering the importance of the study area (geologically), the existence of active and important faults in this region, as well as political-security threats, the existence of spatial exchanges and links on both sides of the border, and the underdevelopment of study and planning in the field of crisis management of this region seems necessary.Also, according to the results of the earthquake return period in this region, raising the level of urban environment flexibility against the stresses caused by the crisis and minimizing the time of rehabilitation and resilience of cities are among the most important factors that should be considered in planning and managing cities.