Integration of local soil effect into the assessment of seismic hazard at the Kharga Oasis, Western Desert, Egypt

Abstract

The effect of local soil is integrated into the assessment of seismic hazard at the Kharga Oasis, Western Desert, Egypt. The work is done by adopting the probabilistic approach of seismic hazard assessment and the site response analysis. The probabilistic approach was utilized based on a homogenous earthquake catalogue, a reasonable seismic source model, and selective ground-motion prediction equations. The site response analysis is performed to describe the interaction between ground motion time series that are well-matched with the results of the probabilistic analysis and the dynamic soil properties defined from the seismic survey. The outputs are presented in terms of the site-specific seismic hazard maps which includes the amplification maps and maps for the expected values of the ground motion at the surface. The amplification maps show that the northern part of the area has the lowest amplification while the middle part of the area has the highest amplification. The maps for peak ground acceleration and spectral acceleration for the return periods of 475 years show that the maximum expected peak ground acceleration for this return period is 100.6 cm/s2. It has the values of 135 cm/s2 at 0.1 s spectral acceleration.

Keywords

• The Kharga Oasis
• Western Desert
• Egypt
• Probabilistic approach of seismic hazard
• Site response analysis
• Amplification maps