准噶尔盆地东部沙帐地区中二叠统平地泉组一段致密油源储组合模式

Composite Model of Sources and Reservoirs for Middle Permian P_2p_1 Tight Oil in the Shazhang Area,Eastern Junggar Basin

综合利用录井、镜下薄片及压汞等资料,对准噶尔盆地东部沙帐地区中二叠统平地泉组一段致密油储集层岩性、储集空间和孔隙结构等特征进行了分析,在此基础上结合平一段致密油纵向岩性组合特征及源储关系,总结了平一段致密油源储组合模式。研究发现平一段致密油储集层岩性以碎屑岩为主,云质类岩石次之,储层孔隙结构具"粗态型"、"偏细态型"和"细态型",储集空间表现为常规孔隙与纳米孔隙并存;平一段源储组合表现为"泥包砂"、"砂包泥"和"砂泥互层"。研究表明:平一段储集层表现为致密储层特征,纳米孔喉是致密油储层的主体孔喉,平一段致密油具有源储一体型、源储交接型和源储隔离型三类组合模式。

This paper studies the lithology,storage space and porosity structure of reservoirs of Middle Permian P2P1 tight oil in the Shazhang area, eastern Junggar Basin by analyzing data of well logs,thin sections and mercury penetration synthetically. Then it studies the lithological composition charac- teristics and relationship between sources and reservoirs and proposes a Composite model of sources and reservoirs. It shows that there are different types of reservoirs among which clastlc rocks and dolomitic rocks are the main rock types. The pore structure is of the coarse type, partial fine type and fine type. In addition,the storage spaee includes conventional pore and nanometer-scale pore and the composition of sources and reservoirs show the characteristics of sand containing mud, mud encompassing sand, and sand and mud interstratification. The results indicate that the reservoirs of P2P1 have the feature of tight reservoirs and the nanometer-scale pore throat plays an important role. In addition,three kinds of source-reservoir structure models are established ：integrat- ed source-reservoir model,connected source-reservoir model and isolated source-reservoir model.