Earthquake Risk Assessing and Mapping for Germany

The aim of this study is to assess and map the seismic risk for Germany. There are several earthquake prone regions in the country which have produced ML magnitudes above 6 corresponding to ground shaking intensity VIII (EMS-98). Combined with the fact that some of these earthquake prone areas are densely populated and highly industrialized and where therefore the hazard coincides with high concentration of exposed assets, the damaging implications from earthquakes must be taken seriously. In this study a methodology is presented and pursued to calculate the seismic risk from [1] intensity based probabilistic seismic hazard, [2] vulnerability composition models, which are based on the distribution of residential buildings of various structural types in representative communities and [3] distribution of assets in terms of replacement costs for residential buildings, which are estimated for all communities of the country. The estimates of risk are treated as primary economic losses due to structural damage to residential buildings. The obtained results are presented as maps of the damage and risk distributions. For a probability level of 90% non-exceedence in 50 years (corresponding to a mean return period of 475 years) the mean damage ratio is up to 20% and the risk up to hundreds of millions of euro in the most endangered communities. The developed models have been validated with observed data from several damaging earthquakes in Germany and the nearby area in the past 30 years.