High-resolution processing for time-lapse seismic

D. Lecerf and C. Reiser, CGG London, review some of the issues in the processing of 4D seismic data. Today time-lapse seismic technology has become an effective reservoir management tool for monitoring fluid flow and detecting undrained reservoir compartments. Geophysicists have taken up the challenge to merge the information available from time-lapse seismic with the output of reservoir simulation models and the available reservoir knowledge. Optimizing this information across the disciplines encounters a major problem of scales and uncertainties. Improving the vertical resolution of the seismic data is a key factor in this overall reconciliation. Improved resolution relies on the ability to recover the high-frequency content of seismic data. CGG has developed a processing methodology that provides a 4D seismic signature with an extended frequency bandwidth. Preconditioning of the seismic data is the key to removal of spatially correlated noise, such as the acquisition imprint, and also random noise, which can contaminate the high-frequency content of the seismic. In addition, working with a larger bandwidth in the time-lapse context forces a review of the conventional frequency matching procedure.