Classification and Evaluation of Micro-Pore Structures in the Ultra-Low Permeability Sandstone Reservoir
特低渗透砂岩储层微观孔隙结构分类评价

With the technology of high pressure Hg injection, the ejection saturation (SE) parameter was defined. By the assessment performance parameter (E), the product of ejection efficiency (EW) and ejection saturation (SE), the characteristics of micro-pore structures were classified in three areas of Yanchang Formation in Odors Basin. The classified results coincide with the production characteristics. Based on the extent of ejection, it is considered that the efficiency can be improved by increasing the pressure difference in the medium-high permeability reservoir, and that the low-velocity water injection should be maintained in the ultra-low permeability sandstone reservoir so as to raise its exploitation effect.