METHOD AND SYSTEM FOR DISTRIBUTED TOMOGRAPHIC VELOCITY ANALYSIS USING DENSE P-MAPS

摘要

The present invention provides a method and system for distributed residual tomographic velocity analysis using dense residual depth difference maps. Prestack seismic imaging is performed using an initial velocity field and interpreted horizons. A residual depth difference is estimated referenced to fixed offset and all horizons. Residual depth difference maps are computed for each offset and each horizon. The residual depth difference maps are back projected to determine slowness perturbation. The initial velocity model may be converted to slowness and the estimated slowness is composited therewith to produce a new slowness volume. The new slowness volume is converted to a new velocity volume for performing prestack seismic imaging. This process is repeated until the slowness perturbation is negligible or reaches a predetermined threshold.