Stress field model for the Marmara Sea Region

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.

Project description

 

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.

Publications

Hergert, T. Heidbach, O.   Numerical stress field modelling of the Istanbul Region   Abstract on Tectonics of strike-slip restraining & releasing bends in continental & oceanic settings: 28-30 September 2005, Geological Society, London

Hergert, T., Eckert, A., Heidbach, O.   Numerical stress field modeling of the Marmara Region   Geophysical Research Abstracts, Vol. 8, 05753, 2006

Hergert, T., Heidbach O., Becele A., Hirn A.   Numerical stress field model for the Marmara Sea Region   Abstract on International workshop on comparative studies of the North Anatolian Fault (Northwest Turkey) and the San Andreas Fault (Southern California): 14-16 August 2006, Istanbul