Critical Evaluation of Strong Ground Motions in Izmir and Implications for Future Earthquake Simulation Results

Abstract

Izmir, a major city in western Turkey, is located in a highly seismic region, subject to frequent earthquakes due to its proximity to active fault systems. This paper critically evaluates the strong ground motions recorded in Izmir, with a focus on understanding the implications for urban infrastructure and future seismic hazard mitigation. Historically available data is collected and compared with the available ground motion prediction equations (GMPE). Later, the most appropriate prediction equation is selected and used to determine the target response spectrum. 2020 Sisam earthquake is a well-documented seismic event and the data from the stations are then used to further calibrate the 1D site response model. Lastly, possible future events are generated and results are compared with the current Turkish Earthquake Code (TEC). Amplification factors prescribed by code for Izmir Bay have been surpassed by projected future events, highlighting the necessity for reassessment. Therefore, region-specific seismic zoning should be established when standard code practices fall short in accounting for significant site effects. Concrete recommendations about local site modification factors and evaluations on this topic have been provided within the article.