An extended stochastic method for seismic hazard estimation
A. K. Abd el-aal1, M. A. El-Eraki2, and S. I. Mostafa21National Research Institute of Astronomy and Geophysics (NRIAG), Helwan, Egypt 2Geology Department, Faculty of Science, Zagazig University, Zagazig, Egypt
Received: 14 Oct 2015 – Accepted for review: 29 Nov 2015 – Discussion started: 21 Dec 2015
Abstract. In this contribution, we developed an extended stochastic technique for seismic hazard assessment purposes. This technique depends on the hypothesis of stochastic technique of Boore (2003) "Simulation of ground motion using the stochastic method. Appl. Geophy. 160:635–676". The essential characteristics of extended stochastic technique are to obtain and simulate ground motion in order to minimize future earthquake consequences. The first step of this technique is defining the seismic sources which mostly affect the study area. Then, the maximum expected magnitude is defined for each of these seismic sources. It is followed by estimating the ground motion using an empirical attenuation relationship. Finally, the site amplification is implemented in calculating the peak ground acceleration (PGA) at each site of interest. We tested and applied this developed technique at Cairo, Suez, Port Said, Ismailia, Zagazig and Damietta cities to predict the ground motion. Also, it is applied at Cairo, Zagazig and Damietta cities to estimate the maximum peak ground acceleration at actual soil conditions. In addition, 0.5, 1, 5, 10 and 20 % damping median response spectra are estimated using the extended stochastic simulation technique. The calculated highest acceleration values at bedrock conditions are found at Suez city with a value of 44 cm s−2. However, these acceleration values decrease towards the north of the study area to reach 14.1 cm s−2 at Damietta city. This comes in agreement with the results of previous studies of seismic hazards in northern Egypt and is found to be comparable. This work can be used for seismic risk mitigation and earthquake engineering purposes.
Abd el-aal, A. K., El-Eraki, M. A., and Mostafa, S. I.: An extended stochastic method for seismic hazard estimation, Nat. Hazards Earth Syst. Sci. Discuss., 3, 7555-7586, doi:10.5194/nhessd-3-7555-2015, 2015.