Publications

Reservoir simulation is a common tool for determining the optimum infill well numbers and placement for oil fields. However, reservoir simulation is an inverse problem, where different models can lead to the same (known) outputs of oil, gas and water rates and reservoir pressures. So we always wonder, “Is our reservoir model a good representation of our actual reservoir?” Uncertainty analysis can help answer this question. But rigorous uncertainty analysis involves building multiple history-matched models which requires a lot of time and effort. This paper will present another way to perform uncertainty analysis using a single history-matched to forecast production for candidate infill wells. The candidate wells were weighted and sensitized with factors having a major impact on production such as oil column, permeability, productivity index, seismic quality and offset wells production performance. This last factor can give us a low-side forecast. If this outcome is still economic, then we have a robust infill drilling candidate. This method was used to screen infill wells in the Malacca Straits PSC in 2010-2011. It proved successful to capture uncertainty in initial oil rate and oil recovery.