Earth Model Building With Full-Waveform Inversion - A Case Study From A Shallow Reservoir In The Barents Sea

Abstract

SummaryThe Wisting field in the southwest Barents Sea is characterized by a shallow reservoir and has a complex geological history. Previous studies in the area showed that imaging the existing surface seismic data in depth with an accurate TTI earth model, and applying compensation for absorption within the migration gave the optimum preservation of AVO for further reservoir characterization. A full-waveform inversion (FWI) model building study was undertaken to derive a high resolution earth model suitable for depth imaging purposes. Anisotropy and absorption quality factor (Q) were derived and calibrated across the available, high quality borehole data in the survey area and incorporated into the starting model. FWI was employed to update the model over the depth range of interest, with reflection tomography used to update below the maximum penetration depth of the FWI. The resulting model is robust, high resolution and consistent with all available well data.