Many alternatives arise during the development of major oil and gas fields. Reservoir simulation has a firmly established role in helping to select which of these alternatives will give the optimum development. This is especially true in the North Sea where development and operating costs are relatively high and it is cost effective to study options in detail before proceeding in the field.
General reservoir simulation principles are now well known by reservoir engineers but they are summarised in this paper as an introduction for a wider audience.
A case history is presented which shows how reservoir simulation has been important at all stages in the development of BP’s Magnus field. Figures are presented to show how estimated Magnus field reserves have changed with the acquisition of new data and improved interpretation techniques. Reserves histories for other major North Sea fields are also discussed.