Reduction of depth uncertainties using common offset RTM (COR) Gathers

Subsalt velocity estimation has presented significant challenges in the past. Ray based methods suffer from poor S/N ratios that results from sparse ray coverage beneath salt bodies. The use of common offset RTM gathers (COR) has been shown to decrease uncertainties in subsalt residual moveout estimation, which can more reliably be used by tomographic algorithms to invert for more accurate velocity estimations. Furthermore COR gathers have been shown to improve salt velocity estimations in areas with sediment inclusions. Better ties to well information (sonic logs, formation markers) have validated the improved resultant velocity models.