Re-Evaluation of the 2011 Mw 5.9 Simav Earthquake: Bayesian Modeling of Co-Seismic Slip Using InSAR, GPS, and Seismic Data

The Mw 5.9 Simav earthquake that occurred on May 19, 2011, in Western Anatolia serves as a significant case for understanding active tectonic processes in an extensional regime. This study investigates fault geometry, slip distribution, and stress transfer parameters by integrating seismic, GNSS, and Interferometric Synthetic Aperture Radar (InSAR) data. Through Bayesian inference and joint inversion methods, the study aims to better understand the co-seismic deformations caused by the earthquake.

Within the Simav Fault Zone, the co-seismic slip distribution and stress transfer between fault segments will be analyzed to calculate potential stress increases and correlate them with the spatial and depth distribution of aftershocks. The study will specifically examine the relationship between NW-SE-oriented stress accumulation and concentrated aftershock activity. Aftershocks will be analyzed using the double-difference relocation technique. Focal mechanism and relocation analyses indicate seismic activity extending to depths of up to 22 km. Furthermore, GNSS data from before and after the 2011 earthquake reveal an extension rate of 30-40 mm/year, shedding light on the evolutionary processes of the graben system.

Previous studies have provided significant insights into the Simav earthquake and have conducted comprehensive analyses regarding the extensional regime and active faulting processes in the region. Building upon these findings, this study aims to present preliminary results and offer new perspectives on fault parameters and stress changes.