以特低-超低渗透砂岩油藏为研究对象,应用恒速压汞技术深入分析其微观孔隙结构,通过低渗透物理模拟试验研究该类储层的应力敏感性、单相流体渗流以及油水两相渗流特征,并从微观孔隙结构角度进行解释,在此基础上讨论该类油藏开发效果的影响因素.结果表明:微观孔L隙结构是决定和影响特低-超低渗透油藏开发难度和开发效果的根本性因素；当渗透率小于2×10-3 μm2时,孔喉微细,储层动用难是开发面临的最核心的矛盾,但储层一旦得到有效动用,因其良好的喉道分选,开发效果会比较好；而当渗透率大于5×10-3 μm2时,流体流动通道较宽,建立起有效的驱动压力体系较为容易,开发此类储层面临的关键问题是微观非均质性降低了储层的开发效果.%The micro pore-throat structures of extra-ultra low permeability sandstone reservoirs were researched through the constant-rate mercury injection experiment. The stress sensitivity, characteristics of single-phase flow and two-phase flow of such reservoirs were studied by means of physical simulation and the origins of these characteristics were discussed in terms of micro pore-throat structures. Based on the above research findings, the factors influencing the development effect of extra-ultra low permeability sandstone reservoirs were analyzed. The results show that the micro pore-throat structures thoroughly determine and affect the development difficulty and development effect of such reservoirs, and that the key problem is tiny throats boosting the development difficulty when the permeability is lower than 2×10-3μm2, while the key problem is micro-heterogeneity lowering the development effect rather than development difficulty when the permeability is higher than 5×10-3 μm2.
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