The crustal state of stress in the Marmara region is simulated numerically. The modeled state of stress at the faults is used to estimate seismic hazard on the respective fault segments.
The 1999 Izmit earthquake is supposed to be a precursor of an expected future earthquake beneath the Sea of Marmara about 20 km south of the city of Istanbul. We simulate the stress field in the Marmara region using a 3D numerical model (Finite Elements). In a first step we focus on the impact of structural variations in the Marmara region on the stress field. The model includes the 3D fault system with Coulomb friction on these so-called contact surfaces, topography, bathymetry, basement and Moho structure. The model is driven by gravity and kinematic boundary conditions on the model sides and from below accounting for the tectonic loading. In order to validate our model we compare the model results with GPS data, fault slip rates, stress orientations and stress regime from earthquake focal mechanisms. In a second step we investigate the modeled stress field with respect to earthquake hazard in the Marmara Sea.
