Static and Dynamic Uncertainty: an Integrated Approach

Abstract

Summary A deterministic simulation model with a “good” history match does not guarantee a “good” prediction. An integrated uncertainty analysis is required to capture all the unknowns in the project and also all the interactions among them. A fit for purpose workflow should be designed to incorporate every uncertain variable (static and dynamic). These should be ranked and accordingly used in the history match. This paper presents a case study of a green field in the North Sea, illustrating that without an integrated uncertainty study, the results just provide one solution to the problem, but it does not account for the uncertainty. In our example, prior to the uncertainty study, the aquifer size was the only variable modified during in the history match when new production data was updated. However, with an integrated approach, several variables were identified whose impact on the history match was found to be as important as the aquifer size. In the independent static and dynamic uncertainty approach these variables were discounted as they did not have a significant impact in the hydrocarbon in place calculation.