Velocity Estimation in Complex Chalk

C005 VELOCITY ESTIMATION IN COMPLEX CHALK Abstract 1 Mick Sugrue 1 Ian F. Jones 1 Emma Evans 1 Stuart Fairhead 2 Gary Marsden 3 1: GX Technology180 High Street Egham Surrey TW20 9DN UK 2: Amerada Hess Corporation USA 3: Amerada Hess A/S Denmark Here we consider a North Sea study where our initial approach was to build the subsurface model using interpreted horizons as a guide to the velocity update. This is common practice in the North Sea where the geology ‘lends itself’ to a layer-based model representation. In other words we encourage preconceived bias as we consider it