Feasibility testing of 4D seismic monitoring with full-waveform tomography

Chad M. Hogan, Kenneth J. Hedlin, Gary F. Margrave, Michael P. Lamoureux

Full waveform tomography reveals subtle sub-wavelength perturbations in the velocity model, given a sufficiently accurate starting model. 4D seismic surveys over fields are typically intended to detect relatively small changes in a relatively well-known overall velocity field due to localized effects such as CO₂ injection, steam injection, petroleum production, and more. Full waveform tomography is ideally suited to detect and reveal the extent of these effects, both spatially and in terms of the magnitude of the effect on the velocity. Our early investigations strongly suggest that waveform tomography deserves serious consideration as a primary analysis tool for 4D seismic analysis.