EARTHQUAKE SCENARIOS FOR THE CITIES OF SOFIA, ROUSSE, AND VRATSA

Global seismic hazard and vulnerability to earthquakes are increasingsteadily as urbanization and development occupy more areas that are prone to effectsof strong earthquakes. The uncontrolled growth of mega cities in highly seismicareas around the world is often associated with the construction of seismicallyunsafe buildings and infrastructures, and undertaken with an insufficient knowledgeof the regional seismicity peculiarities and seismic hazard. The assessment of seismichazard and generation of earthquake scenarios is the first link in the preventionchain and the first step in the evaluation of seismic risk. The territory of Bulgaria (situated in the eastern part of the Balkan Peninsula) represents a typical example ofhigh seismic risk area. Over the centuries, Bulgaria has experienced strong earthquakes. The strongest earthquakes reached magnitude 7.8 in southwestern Bulgaria, magnitude 7.5 in northeastern Bulgaria, and magnitude 7.0 in southern Bulgaria. Moreover, the seismicity of the neighboring countries, like Greece, Turkey, formerYugoslavia and Romania (especially Vrancea-Romania intermediate earthquakes), influences the seismic hazard in Bulgaria. In the present study earthquake scenariosfor three Bulgarian cities (Sofia, Rousse and Vratsa) are presented. The scenarioswere generated using deterministic approach that was applied in the European projectRisk-EU (2001-2004). Such scenarios are intended as a basic input for developingdetailed earthquake damage scenarios for the cities and can be used in earthquake-safe town and infrastructure planning