Water Flooding Laws Of Fractured-porous Weakly Volatile Carbonate Reservoir

During the depletion development of fractured-porous weakly volatile carbonate reservoir,the underground degassing of crude oil is serious,the oil production decreases rapidly,and the production gas-oil ratio increases rapidly.After the adjustment to water injection development,the injected water is easy to flow along the fracture,and the underground oil,gas and water distribution is complex.It is urgent to study the water flooding law of fractured-porous weakly volatile carbonate reservoir,and clarify the fluid distribution and migration characteristics under the condition of water flooding.Firstly,in view of the complex fluid properties of weakly volatile crude oil and the co-development of multiple occurrence fractures in reservoir N,this thesis completed the compound of weakly volatile crude oil,made physical models at the micro scale and core scale,and realized the accurate simulation of weakly volatile fluid and different occurrence fractures.Secondly,the microfluidic experiment method was used to reveal the process of gas phase production oil phase process in the depletion development stage,clarify the distribution and migration characteristics of fluid before and after degassing of micro-scale weakly volatile crude oil,and analyze the micro-scale water displacement mechanism and pattern.At the same time,the variation characteristics of experimental indexes of water flooding were analyzed by using core experiment method,the influence of fracture occurrence on water flooding characteristics was clarified,and the law of water flooding in different water cut stages before and after degassing of weak volatile crude oil at core scale was recognized.Finally,the water flooding quality of N reservoir is analyzed based on the micro scale and core scale water flooding law,combined with the production performance and remaining oil distribution,which helps to understand the fracture development scale and reservoir fluid distribution,and puts forward adjustment suggestions to improve the development effect according to different production performance modes.In this thesis,the water flooding law of fractured-porous weakly volatile carbonate reservoir is recognized from the micro and core scale,and the quality of water flooding in real reservoirs is evaluated,which has certain guiding significance for the development and adjustment of fractured-porous weakly volatile carbonate reservoir and similar reservoir.