四川盆地中部须家河组致密砂岩储层孔喉结构分类评价  

Classification and evaluation of pore throat structure in tight sandstone reservoirs of the Xujiahe Formation in the Central Sichuan Basin

作　　者：王力 刘岩[1,2] 曹茜[1,2] 邓虎成[1,2] 王亮 陈婷[1] WANG Li;LIU Yan;CAO Qian;DENG Hucheng;WANG Liang;CHEN Ting(College of Energy,Chengdu University of Technology,Chengdu,Sichuan 610059,China;State Key Laboratory of Oil&Gas Reservoir Geology and Exploration,Chengdu University of Technology,Chengdu,Sichuan 610059,China)

机构地区：[1]成都理工大学能源学院,四川成都610059 [2]成都理工大学油气藏地质及开发工程全国重点实验室,四川成都610059

出　　处：《东北石油大学学报》2024年第4期41-53,I0003,I0004,共15页Journal of Northeast Petroleum University

基　　金：国家自然科学基金面上项目(41972158);国家自然科学基金面上项目(42072182)。

摘　　要：致密砂岩储层具有非均质性强、孔喉关系复杂和孔渗相关关系差等特点。以四川盆地中部须家河组致密砂岩储层为研究对象,采用高压压汞和核磁共振法表征全孔径分布,建立全尺度的毛细管压力曲线,明确不同孔喉结构特征参数与储层宏观物性的关系,进行致密砂岩储层孔喉结构分类评价。结果表明:高压压汞实验中大孔(孔径≥50 nm)标定的核磁孔径分布可准确表征全孔径分布;全孔径分布谱图计算的峰度参数与孔隙度相关关系好,可评价储层宏观储集能力;伪毛细管压力曲线计算的相关因数和分形维数参数与渗透率相关关系好,可评价储层宏观渗流能力;研究区致密砂岩储层孔喉结构分为3类,由Ⅰ类到Ⅲ类,储集空间类型由残余粒间孔占优势向粒内溶孔占优势变化,峰度逐渐变小,分形维数变大,储集能力和渗流能力下降。该结果为提高致密砂岩气藏勘探与开发效率提供依据。Tight sandstone reservoirs have the characteristics of strong heterogeneity,complex pore throat relationship and poor correlation between porosity and permeability.Taking the tight sandstone reservoirs of Xujiahe Formation in the Central Sichuan Basin as the research object,the full-scale capillary pressure curve was established by using high-pressure mercury injection and nuclear magnetic resonance method to characterize the full pore size distribution,and the relationship between different pore throat structure characteristic parameters and reservoir macroscopic physical properties was clarified,and the pore throat structure of tight sandstone reservoir was classified and evaluated.The results show that the NMR pore size distribution calibrated by large pores(≥50 nm)in the high-pressure mercury intrusion experiment can accurately characterize the full pore size distribution.The kurtosis parameters calculated by the full aperture distribution spectrum have a good correlation with porosity,which can be used to evaluate the macroscopic reservoir capacity of the reservoir.The correlation factor calculated by the pseudo capillary pressure curve has a good correlation with the fractal dimension parameters and permeability,which can evaluate the macroscopic seepage capacity of the reservoir.The pore throat structure of tight sandstone reservoirs in the study area is divided into three categories,from class I to classⅢ.The reservoir space type changes from the dominant residual intergranular pores to the dominant intragranular dissolved pores.The kurtosis gradually becomes smaller,the fractal dimension becomes larger,and the reservoir capacity and seepage capacity decrease.The results provide a basis for improving the exploration and development efficiency of tight sandstone gas reservoirs.

关 键 词：四川盆地中部 须家河组 致密砂岩储层 高压压汞法 核磁共振法 孔喉结构 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]