Three-component and three-dimensional seismic imaging

Shaowu Wang

A fast 3-D converted-wave depth-variant common conversion point binning method was first developed for constant velocity medium and then modified for depth-variant velocity model. The new algorithm is fast while not losing the accuracy of the CCP binning. A 3-D converted-wave numerical model demonstrated its feasibility.

The prestack migration and migration velocity analysis provided a new approach to converted-wave (P-S) processing and imaging. In the prestack migrated CCSP gather, the asymmetry of the P-S ray path is "removed", therefore some conventional processes for P-P can be applied to P-S processing. The new approach is very fast, flexible and stable. The 3-D physical model and 2-D field data examples proved these features.

With the aid of a 3-D P-S physical modeling dataset, two processing flows for converted-wave were evaluated. One is the conventional converted-wave processing flow with CCP binning, P-S NMO and poststack migration. The other is the processing flow with converted-wave prestack migration.