R. Cakir & S.S. Alexander (Department of Geosciences, The Pennsylvania State University, University Park, PA, USA, 16802)

As the basis for quantitative seismic hazard assessment around the city of Izmir in western Turkey, reliable data relating past earthquakes to active faults in the region is essential. Towards that goal this study combines available earthquake data in the form of seismicity and focal mechanisms, past geological and tectonic studies of geologic structure and faults, deformation from ongoing Global Positioning System (GPS) experiments, and remote sensing imagery( Landsat Thematic Mapper) in an integrated GIS database. As shown in this study, the GIS approach facilitates the interpretation of spatial relationships among these observations and increases the likelihood of identifying and correctlly characterizing active faults that may contribute significantly to the seismic hazard of this region. Other important information to be added later to the GIS database includes expanded remote sensing coverage; maps of frequency-dependent attenuation of ground motion; distribution of shallow, surficial deposits that can significantly amplify ground motion at certain frequencies; and infrastructure at risk from earthquake groun motion. This integrated GIS database will then be used to carry out probabilistic or deterministic seismic hazard and risk assessments for Izmir and neighboring populated areas.