Scenario-based Velocity Modeling for<br>Depth Conversion Uncertainty

Depth realizations of reservoir surfaces was required for geocellular modeling of two fields in the MTJDA. In addition, a measure of uncertainty in depth was required. The method of this paper depth applied vertical stretch depth conversion and a primary velocity model that integrated well picks, seismic velocities and time-depth functions with surfaces. The velocity modeling process guided iterative improvement of the input interpretation data. Alternative velocity models were then created using different assumptions to capture variations in velocity interpolation. The largest uncertainties were identified in three plausible alternate models: with less smoothing of the seismic velocities; without seismic velocities; and with shallow gas effects modeled from seismic amplitudes.