吉木萨尔凹陷芦草沟组页岩储层微纳米孔隙成因及含油特征

为深化吉木萨尔凹陷芦草沟组页岩储层孔隙及含油性认识,通过氩离子抛光、场发射扫描电镜、核磁共振、微纳米CT及激光共聚焦实验技术,对芦草沟组微纳米孔隙类型、成因及含油特征进行研究。结果表明,微纳米级孔隙按照成因分为无机矿物晶间孔和有机质生烃孔两大类。微纳米孔隙中重质组分附着于颗粒表面或充填于纳米级小孔中,轻质组分主要赋存于较大的亚微米级孔隙,孔隙中心含水。“甜点”岩性微纳米孔隙孔喉直径主体在100 nm~10μm之间,占比71.8%~93.5%,孔隙类型以无机矿物晶间孔为主,连通性较好且普遍含油。微纳米孔隙具有良好的开发前景,是页岩油提高采收率的重要方向之一。

Genesis and Oil-Bearing Characteristics of Micro-Nano Pores in Shale Reservoir of the Lucaogou Formation in Jimusar Depression

In order to deepen the understanding of the pore and oil bearing in the shale reservoir of Lucaogou Formation in Jimusar Depression.The genesis and oil-bearing characteristics of the micro-nano pores in the Lucaogou Formation were studied by argon ion polishing,FESEM,NMR,micro-nano CT and CLSM.The results show that there are two types of micro-nanometer porosity according to their genesis:intercrystalline pore of inorganic mineral and hydrocarbon generation pore of organic matter.The heavy components in the micro-nano pores are attached to the particle surface or filled in the nano-sized pores,while the light components mainly occur in the large sub-micron pores with water in the pore center.The main diameter of dessert micro-nano pore and throat is between 100nm~10um,accounting for 71.8%~93.5%.The pore types are mainly intercrystalline pores of inorganic minerals,with good connectivity and generally oilcontaining.Micro-nano pore has a good development prospect and it is one of the important directions to enhance oil recovery of shale oil.