The nearest offset distance estimation method for multi-channel analysis of surface waves in slope

In order to reduce the interference of energetic near-field body waves to surface wave identification and to ensure Rayleigh wave components with strong energy to be collected by multi-channel analysis of surface waves （MASW） method in the slope, this study firstly analyzed the Rayleigh wave propagation mechanism induced by the underground passive source on the slope. Secondly, based on geometric seismology, an empirical formula for the minimum offset of the Rayleigh wave generated on the sloping surface is proposed, and the layered slope with undulating interface is established so as to obtain the simulated common shot point records. Then by comparing the surface particle motion trajectory and dispersion calculation results obtained from the common shot point records with the theoretical values and estimated values, the results show that the four physical quantities have a strong correlation, which indicates that the proposed minimum offset estimation method in this study can be adopted to guide surface wave exploration of layered slopes.