Reservoir simulation effectiveness depend so much on the reliability of the model which is worked upon. Reliability of the model depend on the amount of information engineers have about the reservoir which is been modeled, however at the beginning of any reservoir simulation the amount of information known about the reservoir is very limited. To overcome this challenge, history matching is always performed to reconciliate the model with the reservoir it represents. This process of history matching can either be done manually or automatically. In this report manual history matching of the Norne field was done and then after obtaining the best matched model the future production prediction was carried out.
In performing History matching of the Norne field it was done by first, choosing the matching parameters which were field gas oil ratio, field water cut, field oil production rate and field water production total and then base case was established in which the difference between the model and historical performance was determined. Following the selection of matching parameters and establishment of the base case for each parameter various modification were done attempting to reduce difference between historical performance and model performance observed from the base case. The best model was obtained from combined adjustments of vertical permeability and stratigraphic barrier transmissibility multiplier.
After obtaining the best matched model, the production performance prediction was done by conducting several cases of production prediction strategies. In this report strategies which involved two new producer positions/trajectories will be discussed. It include checking effect to reservoir recovery by firstly addition of a new producer only, secondly, on increasing the reservoir pressure through raising injection rate of injector C-2H, and converting gas injector C-1H into water injector and Lastly, checking the effect raising production rate of a new producer.
The best results from the cases in these two producer's trajectories were then compared, and trajectory 2 was found to be more productive as it provided recovery factor of 57.4% by December 01, 2020, while trajectory one best case provided recovery factor of 53.2%.
Although trajectory 2 produced higher recovery factor, it also produce more water compared to trajectory 1, this necessitated performance of economic analysis to determine which of the two strategies is economically viable. From this analysis it was concluded that the strategy which provided the best recovery factor also produced the best incremental NPV from the base case. The incremental NPV from this case is $2.22 billion.