Figure 7
Kirchoff mapping of backscattered surface waves around location 9.5 km. (a) Retrieved forward-propagating Scholte wave from ambient noise interferometry with virtual source located at 8.2 km; (b). the separated backscattered Scholte waves after FK filtering; (c). the converted depth(wavelength)-velocity relationship from the measured dispersion curves using \(depth = 0.4*v/f\); The dispersion curves used for depth(wavelength) conversion are picked from nearby 9 virtual source gathers. (d). earth models and source-receiver configuration for Kirchoff migration; the earth models are re-sampled from the converted depth(wavelength)-velocity relationship as indicated by the red dots. (e). the Kirchoff mapping image for scatters/heterogeneities localization at each depth. The red dash-dotted line represents the interpreted fault location.
