Because the most used finite difference method to calculate wave propagation cannot handle irregular boundaries easily, a hybrid boundary element and finite difference method is proposed. Firstly, the boundary element method is used to obtain the wavefileds along a horizontal boundary which is going to be the boundary condition of the finite difference method in the next stop. Then the finite difference method is applied to obtain the wavefields under the interface. The wavefields are separated to vector P-wave and S-wave constituents, and considering the coherence of P-wave and S-wave in a conversion point, the image condition of cross-correlation between P- and S-waves is applied to obtain discontinuity image underground. Synthetic tests show the effectiveness of the proposed method.
Received 21 May 2017
Published 20 September 2018
GE Zengxi, E-mail: zge(at)pku.edu.cn
Cite this article
LIANG Zuokui, GE Zengxi. Passive Source Reverse Time Migration Method to Image Discontinuity Beneath Irregular Free-Surface[J]. Acta Scientiarum Naturalium Universitatis Pekinensis, 2018, 54(5): 983-993.