Seismic Hazard Analysis and Obtaining Uniform Hazard Spectra for Esfahan Region, Iran

Document Type : Regular Paper


1 Assistant Professor, Department of Civil Engineering, Payame Noor University, Tehran, Iran

2 Professor, Center of Excellence for Fundamental Studies in Structural Engineering, School of Civil Engineering, Iran University of Science & Technology, Tehran, Iran

3 M. Sc, Department of civil, Science and Research Branch Islamic Azad University, Tehran, Iran


The present study was conducted to determine peak ground acceleration (PGA) over bedrock in probabilistic analysis methods for the seismic hazard and uniform hazard spectra at different hazard levels for Esfahan city. A series of statistics containing historical and instrumental seismic data covering from the 8th century A.D. to the now up to a radius of 200 km was employed and seismic sources were modeled up to a radius of 200 km from Esfahan city. For this purpose the method proposed by Kijko (2000) was employed considering uncertainty in magnitude and incomplete earthquake catalogue. Seismic hazard analysis is then carried out for Esfahan city by using SEISRlSK III (Bender and Perkins, 1987) program for 11×13 grid points. Four different attenuation relationships of PGA and SA with logic tree were used to determine the PGA on bedrock. The PGA can be determined for 143 points and the hazard spectra can be specified for 20 points of the city. Covering %2 and %10 probability of exceedance in one life cycle of 50 years are presented. Finally, the uniform hazard spectra was also presented with %10 and %2 of probability of exceedance in one life cycles of 50 years are presented along with New Mark and Hall Spectra.


[1] BHRC, (2005). “Iranian Code of Practice for Seismic Resistant Design of Building, Standard No. 2800, Third Revision”. Building and Housing Research Center, Tehran, Iran.
[2] Berberian, M. (1973). “Preliminary map of epicenters and focal depth”. Geological Survey of Iran.
[3] Nougol Sadat, M.A.A. (1993). “Seismotectonic Map of Iran, Scale 1:1,000,000”.  Published by G.S.I.
[4] Nowroozi, A. (1985). “Empirical relations between magnitude and fault parameters for earthquakes in Iran”. Bulletin of the Seismological Society of America, Vol. 75, pp. 1327-1338.
[5] IIEES, International Institute of Earthquake Engineering and Seismology,
[6] Berberian, M. (1976). “Contribution to the seismotectonic of Iran, Part II, Geological Survey of Iran”. report No. 39.
[7] Ambraseys, N.N., Melville C.P. (1982). “A History of Persian Earthquakes”. Cambridge University Press, Cambridge, Britain.
[8] Kijko, A. (1984). “Is It Necessary to Contrast Empirical Distribution of Maximum Earthquake Magnitude”. Bulletin of the Seismological Society of America, Vol. 74, pp. 339-347.
[9] Moinfar, A.A., Mahdavian, A., Maleki, E. (1994). “A Catalogue of Basic Information of Iran”.
[10] Gardner, J.K. and Knopoff, L. (1974). “Is the sequence of earthquake in southern California, with aftershocks removed, Poissonian? ”. Bulletin of the Seismological Society of America, Vol. 64(5), pp. 1363-1367.
[11] IRCOLD, (1994). “Relationship between fault length and maximum expected magnitude”. Iranian Committee of Large Dams, Internal Report, Iran.
[12] Gutenberg, B., and Richter, C.F. (1954). “Seismicity of the earth and associated phenomena”. Princeton University Press, New Jersey, U.S.A.
[13] Tavakoli, B. (1996). “Major Seismotectonic Provinces of Iran”. International Institute of Earthquake Engineering and Seismology, Internal Document, Tehran, Iran.
[14] Kijko, A. (2000). “Statistical estimation of maximum regional earthquake magnitude Mama. In: Workshop of Seismicity Modeling in Seismic Hazard Mapping”. Police, Slovenia, Geological Survey, pp. 1-10.
[15] Bender, B. and Perkins, D.M. (1987). “SEISRISK-III: A computer program for seismic hazard estimation”. US Geological Survey Bulletin, No. 1772.
[16] Douglas, J.A. (2001). “Comprehensive worldwide summary of strong-motion attenuation relationships for Peak Ground Acceleration and Spectral ordinates (1969 to 2000) ”. ESEE Report, No. 01-1, Civil Department, Imperial College of Science, Technology and medicine, London.
[17] Ghodrati Amiri, G, Mahdavian, A., Manouchehri Dana, F. (2007). “Attenuation relationships for Iran”. Journal of Earthquake Engineering, Vol. 11, pp. 469-492.
[18] Zare, M., Ghafory-Ashtiany, M., and Bard, P.-Y. (1999). “Attenuation law for the strong-motions in Iran”. Proceedings of the Third International Conference on Seismology and Earthquake Engineering, Tehran, Vol. 1, pp. 345–354.
[19] Ambraseys, N.N., Simpson, K.A. and Bommer, J.J. (1996). “Prediction of horizontal response spectra in Europe”. Journal of Earthquake Engineering and Structural Dynamics, Vol. 25, pp. 371-400.
[20] Campbell, K.W. (1997). “Empirical near-source attenuation relationships for horizontal and vertical components of peak ground acceleration, peak ground velocity, and pseudo-absolute acceleration response spectra”. Seismological Research Letters, Vol. 68(1), pp. 154–179.
[21] Thierry- Berge, C., Cotton, F., Scotti, O., Arme, D., Pommera, G., and Fukushima, Y. (2003). “New empirical response spectral attenuation laws for moderate European earthquakes”. Journal of Earthquake Engineering, Vol. 7, pp. 193-222.
[22] Ghodrati Amiri, G., Khorasani, M., Mirza hessabi, R., Razavian Amrei, S.A. (2010). “Ground motion prediction equation and arias intensity for Iran”. Journal of Earthquake Engineering, Vol. 1, pp. 469-492.
[23] Ghasemi, H., Zare, M., Fukushima, Y., and Koketsu, K. (2008). “An empirical spectral ground motion model for Iran”. Journal of Seismology, Vol. 13(4), pp. 499–515.
[24] Coppersmith, K.J. and Youngs, R.R. (1986) “Capturing uncertainty in probabilistic seismic hazard assessments with interpolate tectonic environments”. Proceedings 3rd U.S. National Conference on Earthquake Engineering, Charleston, South Carolina, Vol. 1, pp. 301-312.
[25] Kulkarni, R.B., Youngs, R.R., Copersmith, K.J. (1984). “Assessment of confidence intervals for results of seismic hazard analysis”. Proceeding 8th World Conference on Earthquake Engineering, San Francisco, Vol. 1, pp. 263-270.
[26] Power, M.S., Coppersmith, K.J., Youngs, R.R., Schwarttz, D.P., Swan, R.H. (1981). “Seismic Exposure Analysis for the WNP-2 and WNP-1/4 Site: Appendix 205K to Amendment No. 18 Final Safety Analysis Report for WNP-2”. Woodward-Clyde Consultants, San Francisco, U.S.A.
[27] IIEES, (2002). “Seismic Rehabilitation Code for Existing Buildings in Iran”. International Institute of Earthquake Engineering and Seismology, Tehran, Iran.
[28] Newmark, N.M., and Hall, W.J. (1982). “Earthquake spectra and design”. Earthquake Engineering Research Institute, Monograph Series, Vol. 3.