Feature parameters of micro pore throat in deep section high pressure and low-permeability sandstone reservoir

Abstract：The feature parameters of micro-pore structure in deep section high pressure and lowpermeability sandstone reservoir of Wendong oil field in Dongpu sag were analyzed with the technology of conventional mercury penetration. The ejection saturation （SE） parameter was defined, and the product of ejection efficiency （Ew） and ejection saturation （St） was put forward as the classified appraisal index （E） of the micro-pore structures. The result shows that the types of pores and throats are various, and the heterogeneity of micro-pore structure is intense. There are direct correlations between the physical properties of reservoir and the sorting coefficient of pore throat, that is reverse to the pore throat of the conventional middle-high permeability sandstone reservoirrs and similar to the pore throat of the conventional super-low one. The correlation between the SE/Ew and the physical parameters is low, which differs from the conventional sandstone reservoirrs. The micro-pore structure in deep section high pressure and low-permeability sandstone reservoir of Wendong oil field was classified into three types. The parameter classified assessment indexes （E） of Ⅰ , Ⅱ and Ⅲ were above 11.21, from 2.90 to 11.21 and below 2.90, respectively. From the viewpoint of the feature parameters of micropore structure, the deep section high pressure and low-permeability sandstone reservoirs differsfrom the conventional conventional reservoir. ne~ty. middle-high permeability one, and so does the low one, it belongs to un The main factor that affects the development is the reservoir heteroge