Probabilistic seismic hazard assessment of Italy using kernel estimation methods

Abstract

A representation of seismic hazard is pro- posed for Italy based on the zone-free approach devel- oped by Woo (BSSA 86(2):353-362, 1996a), which is based on a kernel estimation method governed by concepts of fractal geometry and self-organized seis- micity, not requiring the definition of seismogenic zoning. The purpose is to assess the influence of seismogenic zoning on the results obtained for the probabilistic seismic hazard analysis (PSHA) of Italy using the standard Cornell's method. The hazard has been estimated for outcropping rock site conditions in terms of maps and uniform hazard spectra for a select- ed site, with 10 % probability of exceedance in 50 years. Both spectral acceleration and spectral dis- placement have been considered as ground motion parameters. Differences in the results of PSHA be- tween the two methods are compared and discussed. The analysis shows that, in areas such as Italy, char- acterized by a reliable earthquake catalog and in which faults are generally not easily identifiable, a zone-free approach can be considered a valuable tool to address epistemic uncertainty within a logic tree framework.