Evaluation of Earthquake Potential in the Zagros Region (Iran) Using Seismic Strain and Seismicity Parameters

Document Type : Seismology and Engineering Seismology


1 Ph.D Candidate, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran.

2 Assistant Professor, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran.

3 Assistant Professor, Department of physics, Persian Gulf University, Bushehr, Iran.


In this paper seismic strain andGutenberg-Richter b-value are used to quantify seismic potential in the Zagros region(Southwest Iran). Seismicity data of the Zagros are extracted from International Seismological Center and Iranian Seismological Center bulletins in timeinterval 1963 to 2015. The b-values are estimated using Kijko-Sellevoll method. The results represent that b-value varies from 0.62 to0.72in the study region.Low b-values (0.62 and 0.72) are accompanied with higher strain rates (1.22×10-8 and 7.46×10-9) in southern parts of the Zagros indicating more frequent large earthquakes. On the other hand, Low b-values (0.64 and 0.72) and lower strain rates (2.39×10-9 and 8.54×10-10) in northern parts of the Zagros indicate less frequent large earthquakes. Recurrence interval of large earthquakes(M>6) is estimated using the b-values and seismic strain rates.Recurrence interval of large earthquakes in southern parts of the Zagros (7 and 8 years) are shorter than northern parts of the Zagros (19 and 45 years).


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