Migration Velocity Analysis Through Weighted Stacking

Data migrated with an incorrect velocity model exhibit residual moveout that degrades the resulting stack. To measure this misalignment of signal, two weighted stacks are taken from windows centered about events of interest; weights are chosen to segregate near and far ofe the entire process is iterated until convergence. The use of weighted stacks avoids the need for scanning the migrated data for residual moveout, or worse, hand picking the data. The updating relationship is based on ray theory; this allows the use of well known techniques developed for travel time inversion.