Seismogenic Properties of The Crust Beneath the Western Anatolia-Aegean System: Models Vs Observations

One of the most fundamental aspects of earthquake research is to understand the rheological properties of the crust where seismicity develops. A number of studies have shown that the lower crust in extending tectonic regimes, for instance in east Africa is seismogenic. The origin of earthquakes in east African rift system are interpreted in the context of thermal and compositional the crust. Here, we focus on western Anatolia-Aegean extensional region as a primary example for the development of earthquakes throughout the crust where the thickness does not exceed 25 km. We compare predictions of the thermomechanical numerical models against seismicity (frequency-depth) distribution. Namely, stress state throughout the modeled crust is reconciled with the depth variation of seismic moment distribution. Our results help to account for the brittle-ductile transition beneath the Aegean-west Anatolia where the listric fault characteristics of the detachment fault systems has been identified through a number of observations -both in the field and seismic data. This may explain how the extended crust behaves in rather high vs lower strain rates.