基于压汞实验的致密砂岩储层分形特征研究  

Study on Fractal Characteristics of Tight Sandstone Reservoir Based on Mercury Intrusion Experiment

作　　者：王晨 张惠 姚志刚 霍嘉华 WANG Chen;ZHANG Hui;YAO Zhigang;HUO Jiahua(School of Earth Sciences and Engineering,Shaanxi Provincial Key Laboratory of Hydrocarbon Accumulation Geology,Xi′an Shiyou University,Xi′an 710065,China)

机构地区：[1]西安石油大学地球科学与工程学院陕西省油气成藏地质学重点实验室,西安710065

出　　处：《重庆科技学院学报（自然科学版）》2023年第4期7-12,共6页Journal of Chongqing University of Science and Technology：Natural Sciences Edition

基　　金：国家青年科学基金项目“鄂尔多斯盆地长7页岩有机质与黏土矿物相互作用对孔隙演化的影响”(42102178)。

摘　　要：利用压汞实验数据对鄂尔多斯盆地甘泉西部地区致密砂岩储层的分形特征进行分析。研究区长8段储层为低孔特低渗致密砂岩储层,其岩性类型以细砂岩为主,储集空间类型有粒间孔、粒内孔、填隙物内孔和缝状孔隙等。研究区长8段储层的分形特征主要为一段式,其分形维数多大于2.5,非均质性较强。同时,分形维数随着储层物性变差而增加,孔喉特征参数与分形维数的相关性较好,表明孔喉特征对储层的储集性能和渗流能力有一定影响。此外,分形维数与矿物成分之间具有一定的相关性,长石和绿泥石的存在会降低孔隙结构的复杂性,而石英和伊利石的存在则会加大储层孔隙结构的复杂性和非均质性。The fractal characteristics of tight sandstone reservoir in the western Ganquan area of Ordos Basin is studies by mercury intrusion experiment.The results show that the lithology type of Chang 8 reservoir in the study area is a tight sandstone reservoir with low porosity and low permeability,which is mainly composed of fine sandstone.There are intergranular pore,intragranular pore,interstitial pore and fissure pore in the reservoir space.The results also show that the fractal characteristics of Chang 8 reservoir is mainly one section,and most of its fractal dimension is greater than 2.5,and the heterogeneity is high.What′s more,fractal dimension increases with the deterioration of reservoir physical properties.There is a good correlation between pore throat characteristic parameters and fractal dimension,indicating that pore throat characteristics have a certain influence on reservoir performance and seepage capacity of the reservoir.Besides,Fractal dimension is related to mineral composition.Feldspar and chlorite reduce the complexity of pore structure while quartz and illite increase the complexity and heterogeneity of pore structure.

关 键 词：长8段储层 致密砂岩 分形特征 孔喉结构 分形维数 非均质性 

分 类 号：P618[天文地球—矿床学]