The Study On The Heterogeneity Of The Yan 10 Reservoir Of Maling Oilfield In The North Three Area

The Yan 10 reservoir in the north three area of Maling Oilfield has been in the middle-high water stage after 10 years' exploitation,The flooding degree is complicated and the residual oil distribution is scattered and difficult to predict,it is difficult to develop for the next step.Based on the fine division,sedimentary microfacies and local structural features discrimination,this paper studies the heterogeneity of the study area,from the macroscopic and microscopic angles,through scanning electron microscopy,High pressure mercury,constant pressure mercury,oil-water infiltration and true sandstone water flooding experiment,to characterize the heterogeneity,and analyze the influencing factors of heterogeneity in the study area.The main results and conclusions have been agreed as follows:1?The reservoirs in the study area belong to the fluvial facies sedimentary system,and there is a transition from the braided river subfacies to the meandering river subfacies from the top to the bottom.The channel sand bodies are well continuous in the plane,and are superimposed in the vertical direction,The overall structure is relatively gentle,local development microstructure.2?The macroscopic heterogeneity of the reservoirs in the study area is strong in the plane,and controlled by the sedimentary microfacies distribution,and the heterogeneity in each layer is weak,but it is stronger from top to bottom.Interlayer heterogeneity is weak,too.3?The pore types of the reservoirs are intergranular pores,dissolution pore and intercrystalline pore,the pore assembly types are intergranular pores,intergranular pores-dissolution pore,intergranular pores-intercrystalline pore,increases in turn in micro heterogeneity.Through the experiment of high pressure mercury and constant pressure mercury,the micro-heterogeneity of the study area is weak,and the micro-pore heterogeneity is weak,and the heterogeneity of the microscopic throat is strong.4?The different pore structures have different seepage characteristics.The factors influencing the oil displacement efficiency are physical property,heterogeneity,wettability,water flooding multiple and driving pressure.The most important factor is the heterogeneity of pore structure.5?Sedimentation plays a role in controlling the distribution of sand bodies,affecting the heterogeneity of the reservoir in the plane and in layers,resulting in microstructures.The imbalance of diagenesis leads to the microscopic heterogeneity of the reservoir.Waterflooding has led to a different degree of water logging in the reservoir,leading heterogeneity increased.