Fig. 4

We characterize the scattering properties using the diffusion model, in both the experimental granite sample used in the laboratory and the medium of the simulation. The logarithmic representation of the energy density Ln U(t) used for the linear inversion of the mean free path is represented both in the experimental case (red line) and in the simulated case (blue line). The comparison of both functions shows that the numerical medium reproduces the wave scattering happening in the experimental sample. The dashed black line corresponds to the diffusion model with a mean free path l = 3.9 mm