Joint Surface and Borehole Seismic Tomography with Simultaneous Model Parameter Updates at Thunder Horse South
O. Zdraveva, G.A. Solano, S.O. Zaman, E. Saragoussi, A.R. Castelan, S. Chakraborty, Q. Li, C. Joy, K. Hartman and A. Reitz
Event name: 80th EAGE Conference and Exhibition 2018
Session: FWI - Case Histories
Publication date: 11 June 2018
Info: Extended abstract, PDF ( 729.65Kb )
Price: € 20
We present the most-recent effort in fine-tuning the earth model at the Thunder Horse production field. This update was initiated because of and in parallel with the new ocean-bottom node survey acquisition in 2015. To minimize uncertainty in the resulting earth model, the chosen approach relies on using all available information. For this imaging exercise, this entails incorporating six surface seismic surveys with differing geometry, five 3D vertical seismic profile (VSP) surveys, three walk-away VSPs, five zero-offset VSPs, multiple sonic logs and well-depth markers in the earth model building process to derive a single anisotropic model that adequately minimizes misfit for all inputs. To achieve this, we use joint tomography of surface and borehole seismic data with simultaneous updates of model parameters, including the VSP transit times and well-depth markers as a data constraint. This strategy resulted in improved surface and borehole seismic images that better resolve structural complexity and stratigraphic details, yielding a more accurate interpretation and more reliable future well placement.