Depth Surface Generation Workflow For A stack Carbonate Reservoir

Summary Conventional time to depth conversion based on vertical wells, seismic velocities and thickness maps was resulting in high residual inconsistency with horizontal wells information: significant sections of horizontal wells were lying out of their stratigraphic layers hence requiring extensive adjustments but also well relocation. A more pragmatic and systematic approach was required to integrate all available data from all reservoirs in a more consistent and manageable way: COHIBA (Correlated Horizon Intervals and Bayesian Analysis) which enables to integrate all input data (markers, zone logs. thickness and velocity maps, distance from boundary data) along with uncertainties to provide consistent depth surfaces. Such workflow also has significant advantages in terms of data management and reactivity to operational results.