Isotropic angle-domain elastic reverse-time migration

Imaging with scalar and vector potentials

An extended imaging condition can also be designed for elastic wavefields decomposed in scalar and vector potentials, similar to the conventional imaging procedure described in the preceding section. Therefore, an extended image constructed from scalar and vector potentials is

$${I}_{ij} \left ({\mathbf x}, {\boldsymbol{\lambda}} , \tau ... ...ft ({\mathbf x}+ {\boldsymbol{\lambda}} ,t+\tau \right)dt \;,$$ (10)

where the quantities $\alpha_{si}$ and $\alpha_{rj}$ stand for the various wave modes $\alpha=\{P, S\}$ of the source and receiver wavefields, and ${\boldsymbol{\lambda}}$ and $\tau$ stand for cross-correlation lags in space and time, respectively.