SPECTRAL AMPLITUDE BASED PROBABILISTIC SEISMIC HAZARD FOR THE AREA COLOGNE/AACHEN (GERMANY) CONSIDERING THE UNCERTAINTIES OF THE INPUT PARAMETERS

摘要

Probabilistic seismic hazard is calculated for an area near Cologne/Aachen (Germany) in the Lower Rhine Embayment. Using the logic tree technique, the uncertainties of the various input parameters and models are quantified in order to give a measure of the errors to the output hazard. Main input features are different combinations of seismic source zones derived from a detailed neotectonically founded regionalization model, seismicity parameters from a new earthquake databank with unified Mw, distributions of maximum expected magnitudes derived with a technique combining global and regional magnitude data, and attenuation relations selected to correspond to the faulting regime of the investigated area. Medium ("best" estimate) and 84% fractile ("conservative" estimate) hazard maps for 2% probability of exceedence in 50 years are presented based on accelerations at 0.1s, 0.2s, 0.4s, 1.0s and 2.0s periods assuming rock foundation. The frequency dependence of ground acceleration for the cities of Cologne and Aachen are shown in diagrams for a wide range of exceedence probabilities.