Probabilistic Criterion for the Identification of Seismogenetic Areas in Seismic Risk Evaluation

摘要

In the paper one provides a probabilistic method for the macro-seismicrncharacterization at the site. The probability function for the epicentres locationrnP(x,y|M), assumed as a Gaussian distribution function, is calculated by the mainrnseismic parameters, namely the magnitude, the intensity and the location of thernepicentres, for any recorded series of historical events. The final expression of thernprobability function is set by the addition of the single contributions of n Gaussianrnfunctions and is defined by means of the evaluation of the respective unknownrnparameters (the average values, the variances, the correlation coefficients and thernconvex combination coefficients) obtained through a “fitting procedure” minimizingrnthe mean square error of the current moments calculated on the basis of any givenrnset of parameters compared to the average moments estimated on the basis ofrnhistorical data under suitable constraints.rnIn the final part of the paper, this procedure is developed for the probabilisticrntreatment of the epicentres location in a seismic area in Southern Italy, wherernearthquakes occurred in a predefined time range with varying magnitudes arernconsidered as input data. Numerical results show a good agreement with previousrnanalyses, demonstrating that the proposed approach ensures a good approximationrnof the combined probability curves about the epicentral distribution over thernconsidered territory.