特低渗透砂岩储层微观孔隙结构分类评价

基于特低渗透砂岩储层岩心样品的高压压汞测试技术，定义退汞饱和度参数（SE）。以退汞效率（Ew）与退汞饱和度（SE）的乘积作为储层微观孔隙结构分类评价的参数指标，即储层孔隙结构综合评价参数（E），对鄂尔多斯盆地延长组3个特低渗透砂岩储层区块进行分类评价，分类结果与油田实际开发生产特征吻合较好。根据汞退出的难易程度，分析认为中、高渗透储层加大注水压差可提高水驱采收率，而特低渗透储层注水开发保持较低的注水速度，有利于提高开发效果。

Classification and Evaluation of Micro-Pore Structures in the Ultra-Low Permeability Sandstone Reservoir

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.