High-resolution wavefield reconstruction in seismic migration for viscoelastic media

This paper deals with the enhancement of vertical and lateral resolution of seismic sections using the viscoelastic wave equation. We first discuss re asons why, although present migration methods, based on the acoustic wave e quation, can to a limited degree enhance lateral resolution, are unable to enhance vertical resolution. Secondly, we point out that, for wavefield rec onstruction in viscoelastic media, a very difficult problem is encountered that is related to obtaining a reliable inverse to the wavefield reconstruc tion integral equation whose kernel function attenuates exponentially. The classical approach to this problem suffers from inherent instability. In th is paper, we first propose a new method, the multiresolution modeling of se ismic wave propagation, to describe the multiscale behavior of the path dep endent attenuation of the seismic wave. Secondly, we describe a new and rob ust inverse method, the multiresolution wavefield reconstruction in seismic migration for viscoelastic media (MRWR). This approach, imaging from coars e to fine resolution, allows a more detailed geological reconstruction to b e made. Finally, we give some synthetic and real data examples that demonst rate the increase in both lateral and vertical resolution of images that ca n be obtained by the use of MRWR.