The new version of the parametric catalog of Italian earthquakes (CPTI04)

In the framework of the initiative promoted by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) aimed to the preparation of a new hazard map of the Italian territory, a working group operated, starting from the beginning of June 2003, to revise the Catalogo Parametrico dei terremoti Italiani (CPTI99). The work was approached by dividing the entire catalog in three segments: 1. Before year 1000 2. Between years 1000 and 1980 3. After year 1980 Regarding the first two segments, the preliminary activities mainly concerned the insertion of new macroseismic studies, made available after the publication of the first CPTI version (end of 1999) and of the SISFRANCE (France) and ECOS (Switzerland) for relative boundary areas, as well as a revision of the choices among concurrent studies. For the segment after 1980, we made a complete relocation and revaluation of instrumental magnitudes, on the basis of the Catalogo Strumentale dei terremoti Italiani (CSTI Working group, 2001) for the period 1980-1996 and of a revised version of the INGV database, integrated with the main regional networks, for the period 1997-2002. The instrumental catalog was integrated with macroseismic studies and available Ms and Mw magnitude estimates taken from the literature and on-line catalogs. The group also made a revaluation of the empirical relations among different instrumental magnitudes and between macroseismic data and magnitudes using improved criteria. The instrumental and macroseismic magnitudes have been combined by weighted averages to give a uniform values both for Ms and Mw ready to be used to compute occurrence rates and ground motion at site. A preliminary version of this catalog, actually used for the computation of the new seismic map of Italy presented in another lecture of this session, was made available on the web. The catalog includes about 2000 earthquakes with Mw>4.15 from Ancient Times to 2002, while the macroseismic database includes in all more then 70,000 intensity observations