Joint Inversion of P-waves refraction travel times and surface wave dispersion curves

Rayleigh wave dispersion curves and P refraction travel times are jointly inverted through a damped least square algorithm which accounts simultaneously for both datasets, solving for common thicknesses and respective VP and VS values. The velocities are coupled through the introduction of P-wave velocity values that are used for both the refraction and the surface wave forward modelling. Since the sensitivity of surface waves to P-wave velocity is low, the problem is strongly coupled on the thicknesses and weakly coupled on the velocities. The surface wave - P-wave refraction joint inversion algorithm is effective in solving hidden layer problem, which would lead to big interpretational errors in the case of individual inversion of P dromocrones. The approach is effective for inversion of 1D layered models as shown in one example for the inversion of experimental data, leading to better results than individual inversions also in the case of surface wave