Tahiti: Development Strategy Assessment Using Design of Experiments and Response Surface Methods

Abstract

AbstractTahiti field in deepwater Gulf of Mexico is a three-way anticlinal structure trapped against salt, with primary hydrocarbon-bearing turbidite sands ranging from 24,000 to 27,000 ft TVD. The discovery well was drilled in 2002, and two appraisal wells were drilled soon afterwards. Due to significant uncertainties remaining after appraisal, probabilistic methods were used to assess development alternatives.In this study the classical experimental design method was applied and reasonable P10, P50 and P90 reservoir simulation models were designed. Next, we looked upon the development plan by performing a second round of design of experiment runs with uncontrollable uncertainties and decisions as factors. The goal was to validate that the previously selected models reasonably represented P10, P50 and P90 oil recoveries and net present value after including decisions in the design. The validation worked out properly reinforcing the confidence in the model selection. Finally, the polynomial response models were used to explore multiple scenarios by varying decisions across the whole range of uncontrollable uncertainties.The proposed workflow enhances the use of experimental design by combining the technique with response surface methods and rational engineering judgment. The approach is recommended for the evaluation of greenfields when a new perspective of the economic analysis of project decisions is desired.