Three-Dimensional Reservoir Modeling Using Stochastic Simulation, a Case Study of an East African Oil Field

This paper presents a three-dimensional geological reservoir model createdusing stochastic simulation. The oil field presented is an East African oil fieldformed by a structural trap. Data analysis and transformations were conductedon the properties before simulation. The variogram was used to measurethe spatial correlation of cell-based facies modeling, and porosity andpermeability modeling. Two main lithologies were modelled using sequentialindicator simulation, sand and shale. Sand had a percentage of 26.8% andshale of 73.2%. There was a clear property distribution trend of sand and shalefrom the southwest to the northeastern part of a reservoir. The distributiontrend of the facies resembled the proposed depositional model of the reservoir.Simulations show that average porosity and permeability of the reservoirare about 20% and 1004 mD, respectively. Average water saturation was 64%.STOIIP volume of 689.42 MMbbls was calculated. The results of simulationshowed that the south eastern part of the reservoir holds higher volumes ofoil. In conclusion, the model gave a better geological understanding of the geologyof the area and can be used for decision making about the future developmentof the reservoir, prediction performance and uncertainty analysis.