3 research outputs found
Planar Seismic Source Characterization Models Developed for Probabilistic Seismic Hazard Assessment of Istanbul
This contribution provides an updated planar seismic source
characterization (SSC) model to be used in the probabilistic seismic hazard
assessment (PSHA) for Istanbul. It defines planar rupture systems for the
four main segments of the North Anatolian fault zone (NAFZ) that are critical for the PSHA of Istanbul: segments covering the rupture zones of the 1999 Kocaeli and Düzce earthquakes, central Marmara, and Ganos/Saros segments. In each rupture system, the source geometry is defined in terms of fault length,
fault width, fault plane attitude, and segmentation points. Activity rates
and the magnitude recurrence models for each rupture system are established
by considering geological and geodetic constraints and are tested based on
the observed seismicity that is associated with the rupture system.
Uncertainty in the SSC model parameters (e.g., b value, maximum magnitude, slip rate, weights of the rupture scenarios) is considered, whereas the uncertainty in the fault geometry is not included in the logic tree. To
acknowledge the effect of earthquakes that are not associated with the
defined rupture systems on the hazard, a background zone is introduced and
the seismicity rates in the background zone are calculated using
smoothed-seismicity approach. The state-of-the-art SSC model presented here
is the first fully documented and ready-to-use fault-based SSC model
developed for the PSHA of Istanbul