Seismic evaluation and comparison of ground motion characteristics in Kahramanmaras and Hatay provinces following the 2023 Pazarcik-Elbistan Earthquake sequences

Abstract

This study analyzes the Pazarcik and Elbistan earthquakes, which occurred on February 6, 2023 and are among the most destructive seismic events of the 21st century. Since the greatest damage was seen in Hatay in these earthquakes centered in Kahramanmaras, the study aims to contribute to the field of earthquake engineering by evaluating the seismic data obtained from these regions. In the first part of the analysis, peak ground accelerations (PGA) recorded at the stations in Kahramanmaras and Hatay were examined and these data were compared with the DD1 (maximum considered earthquake) and DD2 (design basis earthquake) design levels of the Turkish Building Earthquake Code (TBEC 2018). In addition, the effects of ground properties and proximity of faults on seismic records obtained from various stations were evaluated by examining the PGA distribution spatially. The impacts of factors such as the near-fault effect, directivity effect, ground amplification effect and impulse-like motions were determined by examining the peak ground accelations, peak ground velocities, peak ground displacements and spectral accelerations. The study uses NGA-West2 Ground Motion Prediction Equations (GMPEs) to evaluate peak ground accelerations in stiff soil and to consider impulse and directivity effects. In addition, the applicability of USGS Vs30 maps in Turkiye is evaluated by comparing with AFAD data. These comprehensive analysis provide critical insights from a structural safety perspective on how seismic characteristics change with ground properties and proximity to earthquake sources.