A rigorous simulation study of water coning and edge water encroachment using a sector model

A simulation study was conducted in a shaly sandstone reservoir to study field observed coning behavior of a single well and recommend an optimum production rate for its sustained operation. The simulation model covers a 13 km by 5 km area to enable simultaneous simulation of individual well coning and regional edge water encroachment. The effect of areal grid size on matching the observed coning behavior was investigated using Local Refined Grid (LRG). A 20-meter LRG model was chosen to perform various prediction cases to determine the optimum production rate for the coning well. The model was also used to investigate development options to accelerate the recovery of downdip oil, where a 50 feet shallower oil-water contact is observed. This study shows the utility of sector models to study individual well coning behavior and optimize production rate restrictions due to coning, where the regional oil-water contact is dynamic. Conventional single well radial models are considered inappropriate in such cases.