The Site Effect Investigation with Using Horizontal-to-Vertical Spectral Ratio Method on Earthquake Data, South of Turkey

The study area, which is located near the Anatolian, Arabian and African tectonic plate boundaries and surrounded by major tectonic elements such as Dead Sea Fault Zone, Hacıpaşa Fault Zone, Karasu Fault Zone and East Anatolian Fault Zone, has been severely affected from the earthquakes which caused life and property loss during certain periods in historical and instrumental seismology era. Soil predominant period and amplification values have been obtained using earthquake data with the horizontal-to-vertical spectral ratios (EHVs) method commonly used in site effect studies. The obtained predominant period and amplification values play an important role in predicting possible damages which can occur at the structures within the study area during an earthquake. In this study, nine earthquake data recorded by 23 accelerometers have been used to predict soil effects in the study area located in the southern part of Turkey. The soil predominant period values determined with the help of EHVs vary between 0.06 and 2, and the amplification factor values vary between 2 and 10. In addition, the vulnerability index (Kg) has been calculated to examine the lateral deformation changes that may occur on the soil during an earthquake. Kg ranges between 1 and 40 for the study area. In the final phase of the study, bedrock depth has been calculated with the help of empirical correlations and the deepest bedrock depth has been determined as 188 m. The areas where predominant period values are higher than 1 s, bedrock depth is longer than 30 m and Kg value is greater than 20, will be effected more than other areas by a major earthquake.