【摘要】 鄂尔多斯盆地杭锦旗地区锦72井区孔喉结构复杂，影响储层含气性。针对该区致密砂岩储层强非均质性和复杂孔隙结构的含气性评价难题，基于储层基本特征和测井资料建立了岩性控制下的孔喉结构模型，构建差异化孔喉结构含气性评价体系，实现了研究区复杂储层气水识别，为该区天然气勘探开发提供可靠的技术支撑。研究表明：(1)研究区孔喉类型可划分为长石粒内溶孔-高岭石晶间孔型（Ⅰ类）和岩屑粒内微溶孔-伊利石晶间孔型（Ⅱ类），Ⅰ类以含砾粗粒岩屑砂岩为主，孔径较大连通性好，含气性高，Ⅱ类以中-粗/粗-中粒岩屑砂岩为主，因伊利石作用呈高束缚水特征，孔径小连通性差，含气饱和度低。(2)综合考虑孔喉结构、岩性和物性分析，建立基于变胶结指数m、饱和度指数n的阿尔奇公式含气饱和度计算模型与常规束缚水饱和度计算模型，以实现对研究区含气性的精确评价。孔喉类型由Ⅰ类向Ⅱ类变化时，m值逐渐升高，同时在黏土矿物的控制作用下，Ⅰ类主要发育高岭石，n值稳定，Ⅱ类主要发育伊利石，n值呈增大趋势。(3)根据研究区动态产能特征与静态气水识别结果建立气水识别标准，提高了气水层判别的可靠性，单井验证对比射孔结果具有一致性。该方法有效实现了致密砂岩储层孔喉结构的定量表征，从孔喉结构参数选取角度提高了含气饱和度计算精确度，为研究区含气性精细评价提供了参考价值。更多还原

【Abstract】 The pore-throat structure of the Jin 72 well area in the Hangjinqi area of the Ordos basin is complex, which affects the gas-bearing property of the reservoir. In response to the challenges of gas-bearing property evaluation of tight sandstone reservoirs with strong heterogeneity and complex pore structure in this area, a pore throat structure model controlled by lithology is established based on the basic characteristics of the reservoir and logging data, and a differentiated pore throat structure gas-bearing property evaluation system is constructed, achieving gas-water identification in the complex reservoirs of the study area and providing reliable technical support for natural gas exploration and development in this area. The research shows that:(1) The pore throat types in the study area can be classified into feldspar intragranular dissolution pores-kaolinite intergranular pores type(class I) and rock debris intragranular micro-dissolution pores-illite intergranular pores type(class II). Class I is mainly composed of coarse-grained rock debris sandstone with gravel, with larger pore diameters, good connectivity and high gas-bearing property. Class II is mainly composed of medium-coarse/coarse-medium grain rock debris sandstone, with high bound water characteristics due to the effect of illite, smaller pore diameters, poor connectivity and low gas saturation.(2) A gas saturation and conventional bound water saturation calculation model based on the Archie formula with variable cementation index m and saturation index n is established by comprehensively considering pore throat structure, lithology and physical properties analysis. Under the difference of pore throat structure, the m value gradually increases from class I to class II. Meanwhile, under the control of clay minerals, class I mainly develops kaolinite, with a stable n value, while class II mainly develops illite, with an increasing n value.(3) Gas-water identification standards are established based on the dynamic productivity characteristics and static gas-water identification results of the study area, improving the reliability of gas-water layer discrimination. The single-well verification results are consistent with the perforation results. This method effectively realizes the quantitative characterization of pore throat structure in tight sandstone reservoirs, improves the accuracy of gas saturation calculation from the perspective of pore throat structure parameter selection, and provides reference value for the fine evaluation of gas-bearing property in the study area.更多还原