Numerical reservoir modeling is the most sophisticated tool to prepare field development plans and to facilitate decision-making for investment planning. This study presents geological modeling workflow of Bati Kozluca Heavy Oil Field for selection of the best infill well locations and the optimum EOR method to maximize production.
A 3D geological model was built for Bati Kozluca Field, which has been producing since 1985. Well locations, log data, structural surface of the main reservoir rock, i.e, Alt Sinan Formation and interpreted faults were input to the model. The formation is divided into three different flow units according to petrographic facies. Variogram maps were created for petrophysical properties and porosity was distributed by means of Sequential Gaussian Simulation (SGS). Water saturation to depth relation was generated and distributed. Cut-off values obtained from core data were used to generate net-to-gross.
Based on the geological model of Bati Kozluca heavy oil field, OOIP distribution was estimated and two new infill wells (Bati Kozluca-55 and 56) were drilled in the undrained area. Water saturation and porosity values obtained from well logs of these two wells perfectly matched with the values used in the model. Finally, the model was updated using the data from these wells. Porosity and oil-water contact were considered as variable in the Uncertainty analysis and oil-in-place was recalculated. Hence, the model is ready to be used for dynamic reservoir simulation by which secondary production methods to be decided.
This study presents the first stochastic approach to geological modeling of Bati Kozluca heavy oil field in order to quantify the uncertainty associated with reserve estimation.