Characteristics of leaky surface wave in near-surface

Leaky surface wave is a special type of surface waves generated on shallow surface. Reasonable use of leaky surface wave can improve the accuracy of surface wave exploration. However, the identification of leaky surface wave mainly depends on the appearance of leaking energy in surface waves dispersion, which relies heavily on the manual experience. Especially, the effective judgment cannot be made in complex dispersion energy. We conduct numerical analysis and wave field simulation on surface waves and find that the energy change of leaky surface wave is mainly determined by Poisson's ratio, and the energy peak reaches when Poisson's ratio is between 0.40 and 0.43. Furthermore, the most significant factor affecting leaky surface wave is the thickness of formation parameters. We propose that the presence of leaky surface wave can be identified directly based on formation parameters used for inversion. Based on the sensitivity changes of different formation parameters related to leaky surface wave, the initial model for inversion are corrected to obtain a more realistic velocity model. The effectiveness of the proposed method has been confirmed through extensive experiments. Experimental results have shown that the inversion results are more accurate after parameters correction of the initial model according to the sensitive characteristics of leaky surface wave. The minimum fitting error is less than 5% on the five drill holes dataset. This study compensates for the shortcomings of using scattered energy for discrimination and provides strong basis for the inversion of the S-wave velocity structure.