Research On Micro-pore Structure And Percolation Law Of Xinli Oilfield,Jilin Province

Since the entry into the high water cut development period in Jilin Xinli Oilfield,the remaining oil is highly dispersed.Historically,there is insufficient understanding of dynamic residual oil research and oil-water motion laws.The Fuyang oil layer of Xinli Oilfield has low permeability and complex pore structure.The interfacial and capillary forces in the pores are very different from the interfacial and capillary forces of the highly permeable reservoir.Therefore,it is urgent to study the internal displacement mechanism,microscopic characteristics of reservoirs,seepage characteristics of reservoirs,and the inherent reasons for reservoir development potential and constraints.This paper takes the low-permeability sandstone reservoir of Jilin Xinli Oilfield as the research object,and compares the microscopic pore-throat structure characteristics of sandstone reservoirs with different reservoirs and different physical parameters through constant velocity mercury intrusion,CT scanning and physical experiments.Based on this,the characteristics of seepage flow in positive and negative displacement and starting pressure gradient are studied.The throat radius is the main controlling factor for controlling the permeability of the reservoir.The permeability is not the main controlling factor of the anti-drive effect.The oil that was originally stored in the small pores was also driven out,and a series of important conclusions and understandings such as oil re-aggregation were realized.The research results obtained in this paper have certain guiding significance for the microscopic pore structure,displacement mechanism and seepage law of Jilin Xinli Oilfield,and provide a theoretical basis for the development of Xinli Oilfield.