Prestack correlative elastic least-squares reverse time migration based on wavefield decomposition

A new scheme of wavefield decomposed elastic least-squares reverse time migration

“…The second strategy for wavefield decomposition is the decoupled wave equations (Ma and Zhu, 2003;Li et al, 2007;Zhang et al, 2007;Xiao and Leaney, 2010), which decompose wavefields by solving the P-and S-wave separated wave equations. In recent years, the decoupled wave equations prevail in elastic RTM (Wang and McMechan, 2015;Du et al, 2017;Zhou et al, 2018) and ELSRTM (Gu et al, 2018;Qu et al, 2018;Zhong et al, 2021;Shi et al, 2021;Zhang and Gao ,2022;Liu et al, 2022) because it is easy to implement and does not cause phase shift and amplitude distortion of decomposed wavefields (Duan and Sava, 2015;Du et al, 2017;Gong et al, 2018). However, if migration models are not smooth enough, the decoupled wave equation methods may suffer.…”

“…However, methods in the wavenumber domain suffer from expensive computation. Shi et al (2021), Zhong et al (2021), Zhang & Gao (2022) and Liu et al (2022) constructed the decoupled wave equation and applied it to both source and adjoint wavefields decomposition. It is different in this paper: we propose a compound strategy to suppress P-and S-wave cross-talk artifacts in an efficient way.…”