以柴达木盆地3个难采区块为例,针对其储层物性差、注水效果差、微观结构认识不深入等问题,应用恒速压汞、核磁共振及非线性渗流等室内实验技术,对研究区3个主力区块储层的物性特征及微观孔隙结构特征进行了系统研究。在低渗透油田储层分类系数评价方法的基础上,加入表征裂缝发育程度的的评价参数——脆性指数,形成了符合难采油田开发现状的六元分类系数评价方法。研究表明:难采油田储层整体属于典型的低孔、特低渗透储层,不同区块储层物性特征与孔喉特征参数的差异,均归因于储层微观孔隙结构的差异。开展柴达木盆地难采油田相对富集区块的开发潜力分析评价,其分类结果与油田实际开发生产效果相吻合。 Taking the three difficult blocks in the Qaidam Basin as an example, aiming at the problems of poor reservoir properties, poor water injection effect and poor understanding of the microstructure, this paper applied laboratory experiments such as constant velocity mercury injection, nuclear magnetic resonance and nonlinear seepage. The physical properties of the three main blocks in the study area and microscopic pore structure characteristics were studied systematically. Based on the evaluation method of reservoir classification coefficient of low permeability oilfield, the evaluation index - brittleness index, which characterizes the extent of fracture development, is added to form the evaluation index of six - element classification coefficient in line with the current situation of hard oil recovery field. The research shows that the reservoir in the difficult oilfield belongs to the typical low-porosity and ultra-low permeability reservoirs, and the differences between reservoir physical properties and pore-throat characteristic parameters in different blocks are attributed to the differences in pore structure of reservoirs. The development potential analysis and appraisal of the relative enrichment blocks in the hard-to-tap oil fields in the Qaidam Basin are carried out. The classification results are consistent with the actual development and production results of the oilfields.