A few attempts of producing seismic zoning maps of Iceland have been carried out during the last few decades. The earlier efforts were mostly intuitive and based on iso-seismal maps produced from past earthquakes. In the mid 1990s, an attempt was made to produce an iso-acceleration map based on calculated peak acceleration from past earthquakes, using standard attenuation formulae. This map, which was wrought with many discrepancies, was produced as a National application document (NAD) in conjunction with adoption of Eurocode 8. It was clear, however, that the seismic zoning of the country was inadequate and much more research work was needed to provide a reliable earthquake risk map in the form of peak accelerations. The South Iceland earthquakes of the year 2000 provided a wealth of information regarding measured peak accelerations, earthquake source mechanism and attenuation of seismic waves. Moreover, an intensive study of past historical earthquakes has recently been carried out resulting in an upgraded earthquake catalogue for the whole country. Thus all the ingredients for producing a reliable earthquake risk map for Iceland are in place. In this study, the earthquake catalogue has been extended by generation of future earthquake events in order to prevent historical bias. Based on a new attenuation model for seismic waves, the peak accelerations for the whole country have been calculated for a selected subset of the extended catalogue based on Brune's source spectrum. Thus a fairly stable earthquake zoning map for the whole country has been produced with 475-year peak accelerations. In addition, de-aggregation of this map has been carried out to produce a magnitude and a distance map describing the dominating 475-year event. These maps can be used as a basis for simulation of earthquake time histories at a certain site in concord with the requirements of the Eurocode 8.
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