Vs models from noise cross-correlation in the historical centre of Napoli.

The definition of shear seismic velocities with depth is a basic step for the evaluation of the seismic hazard. Active experiments able to reach great depths are almost prohibitive in densely urbanized contexts like that of Napoli. A valid alternative is the approach based on the non-linear inversion of the average group velocity dispersion curve of the fundamental-mode surface waves obtained from the cross-correlation between synchronous noise recordings at two receivers. We show the VSs models obtained along three paths (inter-station distance from 458 to 940 m) in the historical centre of Napoli, extending up to 170 m of depth. Synchronous noise recordings for 2-6 month span have allowed to verify the cross-correlation stability and be sure to recover Green’s function of the inter-station medium.