In order to clarify the microscopic occurrence state and type of shale oil, and to avoid the influence of water drilling sampling on the distribution of crude oil during the experiment, the typical oil-bearing core of Jimsar shale was selected. The whole process of liquid nitrogen drilling, cutting and grinding was adopted to obtain the microscopic reservoir mineral type and structure, reservoir space type, morphology, and the distribution of C, O, Si, Al, Ca, K, Na, Mg and other elements at the micro- and nano-scale by the combination of full energy spectrum scanning electron microscope, secondary electron imaging and backscattering technology. The enrichment degree of crude oil at the micro- and nano-scale was determined according to the distribution of C element content after removing mineral factors. Combining the mineral rock fabric and reservoir space morphology, the micro- and nano-scale crude oil occurrence states in shale oil was quantitatively characterized. According to the configuration relationship between crude oil and pore-throat, the microscopic pore-throat structure of the reservoir and the occurrence state of crude oil were characterized, and the type of occurrence of crude oil was divided and clarified. Four types of microscopic crude oil occurrence types in the study area were summarized: movable oil in micron-scale macro-pores dissolved by dolomite, movable oil in micro-nano-scale pores between sand particles, semi-bound oil film adsorbed by pore throat walls between sand particles, and authigenic clay minerals bound oil within the intercrystalline pores. 

为了更好地认识页岩油微观赋存状态及类型, 避免实验过程中水钻取样对原油分布的影响, 选取吉木萨尔页岩典型含油岩芯, 采用全程液氮钻、切、磨制样工序, 通过全能谱扫描电子显微镜、二次电子成像及背散射相结合的技术手段, 获得微观储层矿物类型和结构、储集空间类型、形貌以及C, O, Si, Al, Ca, K, Na, Mg等元素在微、纳米尺度的分布。依据去除矿物因素后的C元素含量分布, 判别原油在微、纳米空间尺度的富集程度。结合矿物岩石组构和储集空间形貌, 对微、纳米尺度页岩油原油的赋存状态及分布类型进行直观的定量表征, 并基于C元素含量推测微观含油饱和度的相对变化。针对原油与孔喉的配置关系, 进行储层微观孔喉结构与原油赋存状态的表征, 明确原油赋存类型。总结出研究区4种微观原油赋存类型: 白云质溶蚀微米级大孔道中的可动油、砂质粒间微纳米级孔中可动油、砂质粒间孔喉壁吸附的半束缚状态的油膜以及自生黏土矿物晶间孔内束缚油。