GNGTS 2017 - 36° Convegno Nazionale

GNGTS 2017 S essione 2.1 293 outside of any seismic source described in DISS we consider only the rate obtained from the smoothed seismicity model. This ensemble approach allows the model to be applied to zones for which the fault data are unknown. To take into account the uncertainty relative to the two different completeness in the CPTI15 (historical and statistical) as well as to the join of the two types of rates (from seismic catalog and from slip rate), we create six final ensemble models with different weights (Fig. 2). Fig. 2 - Example of one of the six ensemble models; the color scale represents the annual cumulative rates from Mw 4.45 in each 0.1°x0.1° cell, in a log10 scale. Building a global collaborative earthquake hazard model M. Pagani, J. Garcia, R. Gee, V. Poggi, R. Styron, J. Schneider Global Earthquake Model, Pavia, Italy One of the critical goals of the Global Earthquake Model (GEM) second implementation phase is the construction of a worldwide seismic hazard and risk model. The approach selected for completing the hazard component of this model follows a collaborative approach, which aims at incorporating the foremost knowledge publicly accessible throughout the world. The process of collecting and building the various pieces of the mosaic is on-going (see Fig. 1) and several models have been already loaded to the Openquake-platform (https://platform. openquake.org/) , an online repository for data, models and tools distributed by GEM. All the hazard models uploaded to the platform are represented using the standard format for PSHA input models for the Openquake-engine, GEM’s hazard and risk calculation engine. The availability of a large set of models represented using the same format offers a unique possibility of appraising various characteristics and assessing the current state-of-practice in regional and national probabilistic seismic hazard modelling. In this contribution we discuss comparisons between the characteristics of diverse components of the earthquake source models and of the associated epistemic uncertainties. Particular emphasis is placed on appraising features of similar components in different models developed for the same tectonic environment such as, for example, the scaling of fault lengths in active shallow crust models.