Using 1 -D and 2-D modelling of ground motion for seismic zonation criteria: results for the city of Rome

The geological information collected in the last years by the Istituto Nazionale di Geofisica for the city of
Rome is used to construct 1- and 2-D models of the nearsurface structure. These models are the basis for the
numerical generation of synthetic accelerograms which can simulate the horizontal ground motion (SH waves)
produced in the different areas of the city by a large (M ≈ 7) potential earthquake 100 km away in Central
Apennines. The proposed methodology yields earthquake engineering parameters (peak ground acceleration
and velocity, Arias intensity, energy flux, response spectra) whose spatial variations are consistent with the
damage distribution caused by the strongest earthquakes felt in Rome during its long history. Based on the
macroseismic inforination and the results of the numerical simulations, general criteria for seismic zonation of
the city of Rome are proposed.