Ensemble smoother with multiple data assimilation (ES-MDA) is an advanced assisted history matching technique that is capable of reducing the utilization of existing computational resources while improving the quality of the simulation models by preserving the geological consistency of the model during the history matching process.
The subject reservoir in this paper was modeled using an object based modeling approach with appropriate object size distribution and connectivity. This approach generated a stacked dunes-interdunes complex that models the objects as isolated geobodies as observed in dynamic data.
A set of geological realizations were generated by encompassing to capture the uncertainty in sand geobodies distribution, permeability variation and flow barriers. These geological realizations were history matched using the ES-MDA with covariance localization using the state of art in-house reservoir simulator, GigaPOWERS.
The final model attained an excellent history matching quality and predictability capacity. A comparison between the manual history matching results and the ES-MDA is presented to illustrate the value and the impact of the methodology in reservoir simulation studies. The results obtained strongly encourage the further utilization of the presented methodology for history matching.