鄂尔多斯盆地吴仓堡区块延长组长6储层特征研究

依据鄂尔多斯盆地吴仓堡区块长6储层岩心、扫描电镜、铸体薄片等分析化验数据,该区块长6储层砂岩长石和石英含量较高,岩石类型以细粒岩屑长石砂岩为主,成分成熟度和结构成熟度低。利用毛管压力曲线、渗透率、孔隙度、中值压力、最大进汞饱和度等参数对研究区块长6储层的压汞曲线进行分类评价,将本区毛管压力曲线分为I类、II类和Ⅲ类。吴仓堡区块长6储层岩石类型为含细粒岩屑长石砂岩,砂岩成分成熟度和结构成熟度低,储层以粒间孔、粒内孔为主,平均孔隙度9.17%,平均渗透率1.21×10-3μm2,属特低孔-特低渗储层,孔隙以原生孔隙为主。

Study on reservoir characteristics of Chang-6 reservoir of Yanchang formation in Wu Cangbao area,Ordos basin

Based on the analytical data of core,scanning electron microscopy,casting thin sections of Chang-6 reservoir in Wu Cangbao area of Ordos basin,the analysis results show that the content of feldspar and quartz of Chang-6 reservoirs sandstone is high,and the rock types are mainly of fine-grained lithic feldspathic sandstone,and the compositional maturity and textural maturity are lower.According to morphology of capillary pressure curve and pore structure characteristics parameters,the capillary pressure curve of the study area can be divided into three categories,class I,class II and classⅢ.The rock type of Chang-6 reservoir in Wu Cangbao area belongs to fine grained lithic arkose,the sandstone compositional maturity and structural maturity are lower,the reservoirs are mainly of intergranular pore and intragranular pore,with the average porosity of 9.17% and the average permeability of 1.21x10~(-3)μm~2,belonging to extra low porosity- extra low permeability reservoir,and the pore is given priority to with primary pore.