Differential Evolution Algorithm for Inversion of Rayleigh Wave Dispersion Curves

Rayleigh waves have been used increasingly as an appealing tool to obtain near-surface shear (S)-wave velocity structures. As a geophysical method, inversion of Rayleigh wave dispersion curves has multiparameter, multimodal, highly non-linear characteristics. In this study, we proposed and tested a new Rayleigh wave dispersion curves inversion scheme based on differential evolution (DE) algorithm. To evaluate calculation efficiency and stability of DE to inversion of surface wave data, we set three typical synthetic data sets. Results from synthetic data demonstrate that differential evolution algorithm is a simple, effective Rayleigh wave dispersion curves inversion scheme, which can accurately obtain the required target in a wide search space. Given the number of layers, within the constraints of any initial models, the algorithm can accurately obtain velocity value and thickness value of each layer. So the algorithm can be effectively applied to the Rayleigh wave dispersion curves inversion.