【摘要】 为精细刻画江汉盆地潜江凹陷潜江组3₄段第10韵律(简称Eq3₄¹⁰韵律)页岩的矿物组成、岩相特征组合、孔隙类型和孔径分布,判断孔隙结构的影响因素,寻找最有利的页岩油勘探目标,采用X射线衍射、低温氮气吸附、薄片观察、扫描电镜和能谱分析等方法进行研究.结果发现,潜江凹陷Eq₃4¹⁰韵律的矿物成分主要有白云石、方解石和黏土矿物,以及钙芒硝、石英、长石、石盐和黄铁矿等,主要岩相有泥质云岩相、云质泥岩相、灰质泥岩相和泥质灰岩相;主要孔隙类型为白云石晶间孔、粘土矿物晶间孔和碎屑粒间孔,泥质云岩相和云质泥岩相的页岩孔隙结构较好,主要受白云石、黏土矿物和钙芒硝含量的影响.页岩油储层的总有机碳质量分数和含油性也与这些地质因素密切相关,黏土矿物质量分数约为20%、白云石质量分数约为60%的泥质云岩相为最好的页岩油勘探目标.更多还原

【Abstract】 X-ray diffraction（ XRD）,low temperature nitrogen adsorption,rock pyrolysis,thin section observation,scanning electrochemical microscopy and X-ray energy dispersive spectrometer are used to determine the mineral composition,lithofacies characteristics,pore types and size distribution,and the influencing factors on pore structures of the 10 rhythm of Qian 34 formation( Eq3₄¹⁰ for short) of Qianjiang Sag in the Jianghan Basin. The results show that the mineral compositions of the Eq3₄¹⁰ rhythm are mainly dolomite,calcite,clay minerals,and anisometric glauberite,quartz,feldspar,rock salt,and pyrite. The lithofacies include argillaceous dolomite facies,dolomitic mudstone facies,calcareous mudstone facies and argillaceous limestone facies. Intercrystalline pores of dolomite and clay minerals,and detrital intergranular pores commonly develope in the shales of Eq3₄¹⁰ rhythm. Better pore structures mostly exist in the argillaceous dolomite facies and dolomitic mudstone facies,and their characteristics are mainly affected by dolomite,clay minerals and glauberite,so are the total organic carbon and oil content of shale oil reservoir. The shale with 20% clay minerals and 60% dolomite in argillaceous dolomite facies is the best exploration target for inter-salt shale oil reservoir.更多还原