Project S1: Analysis of the seismic potential in Italy for the evaluation of the seismic hazard

Abstract

The project S1 was aimed at (a) collecting new data and to update the existing databases needed to quantify seismic hazard; (b) promoting new studies on specific fields of knowledge and less-explored areas of Italy; (c) testing new approaches to evaluate seismic potential; (d) bounding slip rate values to use within probabilistic hazard estimates; and (e) preparing the way towards a future seismic hazard map of Italy. It was designed with three scientific parts – nationwide basic data, rheology, and field studies – and implemented into four tasks: 1) earthquake geodesy and modeling, 2) seismological data and earthquake statistics, 3) earthquake geology, and 4) tsunamis. Although with many difficulties and some delay, described in the appropriate section, all the above objectives have generally been accomplished. New observations were collected through original fieldwork and more sophisticated analyses were performed on existing data. Datasets needed for the seismic hazard estimates were updated at various levels by reducing both epistemic and aleatory uncertainties. New studies were carried out on specific fields of knowledge, e.g. addressing the repeatability of geodetic and stress data measurements or the seismogenic behavior of misoriented faults. Studies on less-explored areas were stimulated, and faults, whose seismic potential was not previously accounted for, were mapped and/or parameterized in the Ionian and Adriatic Seas, in Calabria, Sicily and the Southwestern Alps. Independent approaches to evaluate the seismic potential were tested, and a large effort toward homogenization and verifiability was made. The substantial improvements of nationwide datasets and understanding of the tectonic processes in large areas of the country set the basis for a significantly better assessment of seismic hazard.