吉木萨尔芦草沟组页岩油储层润湿性特征与影响因素分析

润湿性是页岩储层的重要物性之一，关系到开发方式的制定和生产制度的优化。借助Amott法与接触角法测定了吉木萨尔芦草沟组储层不同岩性样品的润湿性并对比了两种测试结果的差异；通过RoqSCAN技术测定了岩心表面矿物组分，结合原油组分分析了吉木萨尔芦草沟组储层在不同工作液下的润湿特征并分析了组分对润湿性的影响。此外，通过渗吸驱油实验讨论了润湿性对渗吸驱油效率的影响并筛选了适用于吉木萨尔的表活剂类型。结果表明：岩性与原油物性是影响吉木萨尔芦草沟组储层润湿性的关键因素，其中石英、绿泥石、伊利石含量更高的层段亲水性更强，白云石、黄铁矿、伊蒙混层及高岭石含量更高层段亲油性更强，长石含量对吉木萨尔芦草沟组润湿性的影响不大，原油中胶质沥青质含量更高层段亲油性更强。芦草沟组储层在地层水与瓜胶压裂液环境下普遍偏油湿，非离子类表活剂更加适用于吉木萨尔芦草沟储层，改变润湿性的性能更加稳定，能显著提高亲油岩心的渗吸驱油效率。

Investigation on wettability characteristics and influencing factors of Lucaogou shale oil formation in Jimusar

Wettability is one of the most important properties of shale reservoir which closely relates to the planning and optimization of the reservoir development mode. The wettability of the samples with different lithology from Lucaogou Formation of Jimusar was measured by Amott method and contact angle method. The mineral constituents of sample surface were measured by RoqSCAN technology. Combined with crude oil components, the controlling factors and wettability characteristics of Lucaogou Formation under different working fluids were analyzed. Moreover, the influence of wettability on imbibition displacement efficiency was also investigated by imbibition displacement experiment. The results show that lithology and crude oil property are the main controlling factors of the wettability of Lucaogou shale oil formation. The layers with higher content of quartz, chlorite and illite are more hydrophilic, while layers with higher dolomite, pyrite, and kaolinite are more hydrophilic. Feldspar content has little effect on the wettability of Lucaogou formation, and layers with higher content of colloid asphaltene is less hydrophilic. Lucaogou formation is more oil-wet under formation water and guar gum fracturing fluid. Nonionic surfactant is more suitable in Jimusar Lucaogou as it can alter the wettability of Jimusar reservoir more stably, and it can significantly improve the imbibition oil displacement efficiency.