陆相混积型页岩储集层孔隙结构特征及其控制因素  

Pore Structure Characteristics and Controlling Factors of Continental Mixed Shale Reservoirs

作　　者：周新锐 王喜鑫 李少华[1] 张昌民[1] 胡凯 严春景 倪雪儿 ZHOU Xinrui;WANG Xixin;LI Shaohua;ZHANG Changmin;HU Kai;YAN Chunjing;NI Xueer(School of Geosciences,Yangtze University,Wuhan,Hubei 430000,China;Key Laboratory of Oil and Gas Resources Research in Gan-su Province,Lanzhou,Gansu 730000,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lan-zhou,Gansu 730000,China;Geology Research Institute,Greatwall Drilling Company,CNPC,Panjin,Liaoning 124010,China)

机构地区：[1]长江大学地球科学学院,武汉430000 [2]甘肃省油气资源研究重点实验室,兰州730000 [3]中国科学院西北生态环境资源研究院,兰州730000 [4]中国石油长城钻探工程有限公司地质研究院,辽宁盘锦124010

出　　处：《新疆石油地质》2023年第4期411-420,共10页Xinjiang Petroleum Geology

基　　金：中国石油科技创新基金(2021DQ02-0106);甘肃省油气资源研究重点实验室开放基金(20221227)。

摘　　要：陆相混合沉积岩岩性复杂,储集层物性差异大,其孔隙结构及其主控因素,是揭示陆相混积型页岩储集层物性的关键。通过岩石薄片、铸体薄片、扫描电镜、高压压汞、恒速压汞、X射线衍射等,识别了吉木萨尔凹陷二叠系芦草沟组页岩储集层岩性,分析了不同岩性的孔隙结构特征及其与成岩作用的关系。芦草沟组页岩储集层主要发育泥晶白云岩、粉砂质砂屑白云岩、石灰质粉砂岩、石灰质泥岩、粉砂质凝灰岩和石灰质凝灰岩6种岩性。粉砂质砂屑白云岩、石灰质粉砂岩和粉砂质凝灰岩压实程度中等,溶蚀孔发育,孔喉半径大,孔隙连通性及孔喉分选好,储集层物性好;石灰质凝灰岩压实作用中等,主要以方解石、自生石英及方沸石胶结为主,储集层物性中等;泥晶白云岩和石灰质泥岩成分单一,压实作用较强,溶蚀作用弱,孔喉半径小,物性差。Continental mixed shale reservoirs are characterized by complex lithology and varying physical properties.The pore structure characteristics and controlling factors are crucial for understanding the physical properties of such reservoirs.Through analysis of rock thin section,casting thin section,scanning electron microscopy,high-pressure mercury intrusion,constant-rate mercury intrusion,and X-ray dif-fraction,the lithologies of the shale oil reservoirs in the Permian Lucaogou formation in the Jimsar sag were identified,and the pore struc-ture characteristics of different lithologies and their relationships with diagenesis were analyzed.6 lithologies are found in the shale reser-voirs of the Lucaogou formation,namely micrite dolomite,silty sandy dolomite,calcareous siltstone,calcareous mudstone,silty tuff and cal-careous tuff.The silty sandy dolomite,calcareous siltstone,and silty tuff are moderately compacted,with well-developed dissolution pores which are effectively connected and have large and well-sorted pore throats,indicating good physical properties.The calcareous tuff is also moderately compacted,and mainly composed of calcite,authigenic quartz and analcite cements,indicating moderate physical properties.The micritic dolomite and calcareous mudstone are simple in composition,strongly compacted,and weakly dissolved,with small pore throats,indicating poor physical properties.

关 键 词：芦草沟组 陆相混积型页岩 复杂岩性 扫描电镜 高压压汞 恒速压汞 孔隙结构 差异成岩作用 

分 类 号：TE122.23[石油与天然气工程—油气勘探]