Towards an Earthquake Early Warning System for the Megacity of Istanbul

Abstract

Due to the immediate vicinity of the North Anatolian Fault Zone, overpopulation and concentration of industries and infrastructure, Istanbul has developed to a megacity with extremely high vulnerability against earthquakes. Earthquakes with a destructive potential for Istanbul may happen along an about 250 km long zone extending from Adapazari-lzmit some 150 kin east of Istanbul via the Marmara Sea area immediately south to some 100 to 150 kin southwest of Istanbul. An earthquake Early Warning System for Istanbul will have to face the fact that the warning time for most of the relevant earthquakes will be extremely short. The system introduced here, therefore, regards ``Early Warning{''} in a wider sense comprising a rapid post earthquake information component in addition to the timely Early Warning capability. Altogether, the concept presented has four components: a long-term component (stocktaking, preparation phase) a medium-term component (years to days before an earthquake) a short-term component (earthquake happened, but the destructive seismic waves have not yet reached the urban area) an instantaneous component (earthquake hit urban area and rapid earthquake information is necessary). The Early Warning System outlined in the paper may, thus, contribute to reducing economic losses and saving lives by improving the information base for earthquake disaster prevention, automatically protecting against important secondary earthquake hazards and providing rapid earthquake information relevant to disaster management.