Istanbul at the threshold: An evaluation of the seismic risk in Istanbul

There is no convincing evidence indicating that future ground motion in at least two-thirds of Istanbul, Turkey, shall be less demanding than the ground motions that devastated the city of Duzce, Turkey, in 1999. Comparison of vulnerability indices calibrated for Turkish construction indicates that the structures of the buildings in Istanbul are no better than the structures of buildings in Duzce. On the basis of these arguments, we project that a future earthquake near Istanbul may cause severe damage or collapse approximately quarter of a million buildings. Leaving the vulnerable buildings as they are and organizing for emergency response is not an option for Istanbul.