The Z240 area in Heshui area is the main well area for tight oil development in Changqing Oilfield. With the development of tight oil exploration and development, the production capacity of tight oil and gas is declining and the difference of oil content is becoming more and more prominent, which is closely related to the reservoir heterogeneity to a certain extent. In order to clarify the heterogeneity characteristics of Chang 71 tight reservoir in the study area, this paper studied the heterogeneity characteristics of Chang 71 tight reservoir from macro and micro perspectives based on core test data, logging data and mercury injection data. Results showed: (1) from the macro perspective, intraformational heterogeneity is mainly affected by different gravity flow sedimentary sand body and different types of interlining development characteristic, the influence of interlayer heterogeneity is closely related to the development degree of interlayer and plane heterogeneity is controlled by deep water sedimentary environment, the horizontal sand body connectivity and plane distribution of porosity, three aspects are characterized by Chang 713 strongest heterogeneity. (2) From the microscopic point of view, the Chang 71 tight reservoir has a high content of many kinds of interstitials, and the pore throat size distribution is uneven and significantly different, mainly nanometer pore throat, and its heterogeneity is strong on the whole. |