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Shear-wave velocity is a soil mechanical property. It is the main cause of local ground-motion amplification, and it is responsible for a large amount of the damage. Therefore, it is crucial to investigate the soil characteristics down to bedrock to investigate the potential site effect. In this study, seven points in Ras Samadai area have been chosen to be investigated using Multichannel Analysis of Surface Waves (MASW) and Shallow Seismic Refraction (SSR) as active seismic methods. Furthermore, the Frequency-Wavenumber (f-k) and Horizontal-to-Vertical Spectral Ratio (HVSR) techniques were used as passive techniques to obtain the subsurface seismic velocity models and evaluate the site effect beneath the investigated points. The shallow and deep 1-D shear wave velocity models have been obtained at the chosen points using the MASW and f-k approaches. Furthermore, the research area is divided into three main layers based on the seismic refraction approach. At certain cross-sections, there are clear variations in the layers thickness resulting from faults effect. The HVSR method displays two different kinds of curves: flat and one peak curves, due to the variation in impedance contrast between the bedrock and the overlying soil. Moreover, the obtained vulnerability index (Kg) indicates that there is low level of hazards could happen in the study area. Finally, the 2-D lithological models are created to delineate the underground fault lines and displays the lateral variations in lithological composition. This information is useful for the seismic hazard analysis in terms of ground response prediction at ground surface and soil column.

来源平台：MODELING EARTH SYSTEMS AND ENVIRONMENT