关键词: 岩石孔隙结构, 水驱油效率, 相对渗透率, 岩样孔隙结构, 效率影响, 孔隙结构特征参数, 均质系数, 压汞, 润湿性, 相关系数

Abstract: It is proposed in the paper to use the coeffecient of microscopic homogeneity α as the characteristic parameter for pore structure homogeneity.This coefficient is derived from the curve of capillary pressures on mercury injection representing the deviation of the maximum radius of throat from the general trend of distribution of the radii of the throats.The greater the coefficient,the more homogeneous the rocks.It has been noticed that there is no evident relationship between α and air permeability,though it is related to porosity in some way.There is a good linear re Iationship between α and recovery by flooding.In case the rock is water-wet,a better representation of the relationship between the pore structure and the oil recovery efficiency may be obtained with the parameters β derived from the curve of eapillary pressures on mercury withdrawal.There exists a corresponding relationship between α and the mormalized relative permeability carves,the greater the α,the slower the increase of water permeability and decrease of oil permeability.The relationship of α with oilrecovery efficiency is closer than with the other parameters representing pore structure homogeneity.Prediction of the of oil recovery by flooding in rocks of samples from deveral oil fields by means of charts showing the relationship of α and sweep efficiency of water has proved an error of not more than 11% of laboratory results.