Elastic wavefield imaging using the energy norm

From the elastic wave equation and the energy conservation principle, we derive a new imaging condition for elastic wavefields. This imaging condition outputs a single image representing the total reflection energy and contains individual terms related to the kinetic and strain energy of the extrapolated wavefields. An advantage of the proposed imaging condition compared to alternatives is that it does not suffer from polarity reversal at normal incidence. This imaging condition also accounts for the directionality of the wavefields in space and time and can be adapted for attenuation of backscattering artifacts in elastic reverse-time migration. Numerical experiments show the quality of energy images compared to conventional counterparts, and the effectiveness of the imaging condition in attenuating backscattering artifacts.