Quantifying Uncertainty in Final Seismic Depth Image Using Structural Uncertainty Analysis - Case Study Offshore Nigeria

Important decisions, such as drilling decisions and economic evaluations, are often based on interpretation of one seismic image of the target area. The assumptions made when creating this specific image are usually well-known; however, the uncertainty associated remains unquantified. This work presents a case study of the application of structural uncertainty analysis (SUA). Starting from a final depth imaging image, SUA has been used to quantify the uncertainty in the positioning of the target horizons, target surface and thus positioning of the well trajectories due to the TTI model uncertainty only. This is achieved by generating 500 models that equally satisfy the data, and, by then repositioning the targets using map migration. Finally, statistics and displays are generated to estimate and visualise the structural uncertainty.