Study On Reasonable Development Strategy Of Gas-cap Reservoir With Edge Water By Reservoir Engineering Methods

Gas-cap reservoir with edge water is a kind of complicated reservoir type.Because of its unique combination of fluid,the disequilibrium of gas cap and edge water energy will affect interface migration laws of oil-gas and oil-water,causing gas channeling and water flooding too quickly during the exploitation.What's more,the interfacial migration law of fluid is various under different aquifer energy and diverse collocation of production parameters.Therefore,the study of oil-gas and oil-water interfacial migration law under different working system will be of great importance in making reasonable development strategies,extending the production life of oil well and improving oil recovery.JZ 25-1S is a typical gas-cap reservoir with edge water.Because of its unique geological structure which is surrounded by gas upside and water downside,the interfacial migration law of this reservoir is more complicated compared with conventional gas-cap reservoir or edge water reservoir.Based on reservoir engineering method,this thesis analyzes the typical influencing factors of interfacial migration law of fluid.With the aid of MATLAB software,the study on interfacial migration law of fluid(oil-gas/oil-water)and interfacial morphology under different aquifer energy and working system is conducted.Two different schemes of reasonable working system are obtained based on the interfacial migration law of fluid and field actual demand.At the same time,the research results are applied to oil field: For those undeveloped blocks,reasonable guidance is given;for the developed blocks,the historical migration distance of the fluid interface is calculated,meanwhile,the migration distance of the fluid interface and the formation pressure of target areas in a short period can be predicted.The interfacial migration law of fluid,characterization methods of morphological changes of interface and the schemes of reasonable production system combination based on reservoir engineering method are suitable for different types of gas-cap reservoir with edge water,which,therefore,can provide guidance for the development of similar reservoir efficiently.