Research On The Development And Geological Characteristics Of Oil And Gas Buffer On The Gas Cap Of The South Block In Lamadian Oil Field

The gas cap and the oil is a unified hydrodynamic system in the gas cap reservoir. Thereservoir keep a dynamic balance before being developed. While the gas or oil is developed,the pressure drops affect each other, which aroused the interfacial change and cross flow intwo kinds of fluid.Aiming at the difficult development and the cross flow in the oil and gas buffer of gascap reservoir, the effective development mode was studied through theoretical study and fieldtest of exploration of gas cap reservoir. According to the study of the gas sand microfaciesidentification method of oil gas area, sand body connectivity characteristics and phasecharacteristics,3D geological model of oil gas buffer in the South Block gas cap reservoirwas established, which was the fine geology description. Through the basic seepage theoryresearch and indoor core simulation experiment, the make clear the percolation mechanism ofoil and gas near the interface was described, based on which the oil and gas buffer of gas capreservoir was developed efficiently. The oil and gas buffer field test in the south part ofLamadian oil field was carry out. The establishment, maintainance and monitor method ofbarrier, oil and gas buffer development mode and pressure system control method wereresearched systematically. The results showed that the barrier well near the oil gas interfaceinjecting polymer to establish barrier could separate oil and gas, so that developed oil bypolymer flooding. The research achieved good results in application, which had importantguiding significance for other gas cap reservoir. The research results had a good prospect ofapplication and extension.