EGU23-7724, updated on 25 Feb 2023
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Earthquake source parameters in the Zagros region (Iran) from the time of evolutionary P-wave Displacement 

Sahar Nazeri1, Fatemeh Abdi2, Amir Ismail3, Habib Rahimi2, and Aldo Zollo1
Sahar Nazeri et al.
  • 1University of Naples Federico II, Department of Physics, Napoli, Italy (
  • 2Institute of Geophysics, University of Tehran, Tehran, Iran
  • 3Department of Geology, Faculty of Science, Helwan University, Cairo, Egypt

The rupture process of the recent moderate-to-large earthquakes in the longest seismic sector in Iran's plateau, the Zagros area, has been modeled using the strong motion data provided by the Iranian Building and Housing Research Center (BHRC). The selected dataset includes the largest and deadliest seismic event, the 2017 Mw 7.3, Sarpol-e Zahab earthquake. The earthquake source parameters (moment magnitude, source duration, rupture dimension, and average stress drop) are determined by implementing a parametric modeling technique in the time domain based on the time evolution of the P-wave displacement signals. The seismic source parameters are calculated from simulated trapezoidal and triangular moment-rate functions assuming the unilateral rectangle and circular crack models, respectively, where the rupture propagates at a constant velocity as a fraction (90%) of the average shear-wave velocity in the medium. The anelastic attenuation effect assuming the independent frequency-Q parameter ranging from 50 to 200 is accounted for by a post-processing procedure that retrieved the observed moment-rate triangular shape. Hence, the average stress drop with different varies between <Δ𝜎>=1.50 (1.14−1.95) and <Δ𝜎>=0.90 (0.71−1.14) MPa. Assuming a circular rupture model for Sarpol-e-Zahab, we estimate a moment magnitude of 7, rupture duration of 7 seconds, source radius of 16 km, and statistical stress drop of about 3.5 MPa. Alternatively, a unilateral rupture model calculates the fault length and width at 45 and 16 km, with a lower stress drop of 2 MPa.

How to cite: Nazeri, S., Abdi, F., Ismail, A., Rahimi, H., and Zollo, A.: Earthquake source parameters in the Zagros region (Iran) from the time of evolutionary P-wave Displacement , EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-7724,, 2023.