Non-linear Full Wavefield Inversion Applied to Carboniferous Reservoirs in the Wingate Gas Field (SNS, Offshore UK)

A high resolution full wavefield inversion (FWI-res) has been conducted over sub-cubes from the Wingate 3D seismic survey. Three wells provide calibration to the prestack elastic inversion of a deep-seated Carboniferous reservoir section. The non-linear FWI-res technique uses higher order scattering (or multiple energy) to constrain the output. The inversion is performed on migrated seismic data, including a demigration step over the target interval. This object oriented approach is possible in the plane wave (Taup) domain, when assuming a layered medium immediately below the target location. The FWI-res inversion scheme requires only limited user input: cleaned-up Common Image Gathers, top horizon to demigrate the data and a velocity model. Data pre-conditioning is carried out by dip filtering in the timespace domain. This new trace-by-trace inversion is robust and satisfactory results are obtained even in poor data zones.