Abstract

We deployed a temporal network of 24 broadband stations that continuously measured seismic ambient noise in order to investigate the intermediate and deep structure of the Santiago basin for seismic site-response evaluation. Empirical Green's Functions (EGFs) for selected pairs of stations at different frequency bands were obtained from time-domain cross-correlation of the extended seismic noise records. The EGFs were used to estimate phase velocity dispersion curves and shear wave velocity profiles. The resolution of the method allows solving intermediate depths associated to periods from 0.25 to 2 s, a critical period range for infrastructure. The results show average shear wave velocities between 1,250 to 1,450 m/s for depths larger than 150 m and velocities around 800 m/s for gravelly soil deposits of the central area that are consistent with single-station H/V spectral ratio results.