四川盆地东部侏罗系陆相页岩优质储层发育机理及其油气地质意义  

Development mechanism and petroleum geological significance of Jurassic high-quality continental shale reservoirs in the eastern Sichuan Basin

作　　者：李雄[1] 舒逸 刘皓天[1] 陈绵琨[2] 彭伟[2] LI Xiong;SHU Yi;LIU Haotian;CHEN Miankun;PENG Wei(Sinopec Jianghan Oilfield Company,Qianjiang,Hubei 433124,China;Exploration and Development Research Institute,Sinopec Jianghan Oilfield Company,Qianjiang,Hubei 433124,China)

机构地区：[1]中国石化江汉油田分公司 [2]中国石化江汉油田分公司勘探开发研究院

出　　处：《天然气工业》2025年第1期80-93,共14页Natural Gas Industry

基　　金：国家自然科学基金项目“单一纹层对湖相纹层状页岩含油气和储集的非均质性影响机理研究”(编号:42302145);中国石化“十条龙”科研项目“复兴侏罗系陆相页岩油气藏地质评价技术”(编号:P21078-2)。

摘　　要：四川盆地东部复兴地区涪页10井在侏罗系自流井组东岳庙段测试获得高产油气流,进一步证实了陆相页岩具有巨大的油气勘探潜力。但东岳庙段页岩具有高黏土矿物含量、富介壳夹层和较高有机质热演化程度等特殊性,是一种新类型陆相页岩,其优质储层发育特征及影响因素尚缺乏系统研究。为此,综合利用X射线衍射、薄片鉴定、氩离子抛光扫描电镜、压汞—液氮吸附联测、主微量元素分析和纳米CT等多技术手段,深入剖析了东岳庙段陆相页岩储层发育特征,探讨了优质页岩储层发育的控制因素,最后明确了其油气地质意义。研究结果表明:(1)东岳庙段陆相页岩具有“多孔缝共生—无机孔为主—大孔大喉”的储集空间发育特征,发育以黏土矿物晶间孔为主的8种类型孔隙和成岩收缩缝、生烃超压缝等类型微裂缝,无机孔占比为80%~90%,孔隙结构以介孔和宏孔为主,页岩孔喉半径较大,纹层状介壳/粉砂黏土页岩相和纹层状介壳黏土页岩相2种纹层状页岩具有较好的烃源岩品质,为东岳庙段优质储层类型;(2)纹层状介壳黏土页岩相储层具有“高黏土矿物扩孔—高演化生孔—层偶界面成缝—超压保孔缝”的成储机制,沉积环境控制了纵向上页岩垂向非均质性,高黏土矿物含量对增大储集空间有积极作用,半深湖沉积环境保障了优质岩相的发育,纹层沉积构造与页岩形成的层偶界面为应力弱面,易形成微裂缝;(3)较高有机质热演化阶段发生的黏土矿物转化作用、有机质热解和溶蚀作用直接影响了“大孔大喉”的储集空间特征,超压系统、致密介壳隔层为孔缝的保持奠定了保存基础。结论认为,取得的研究成果进一步完善了陆相复杂岩相页岩优质储层发育机理认识,丰富了中国陆相页岩油气地质理论,为新类型陆相页岩油气的勘探选区、选层提供了理论指导。The high-yield oil and gas flow tested by Well Fuye 10 in the Dongyuemiao Member of Jurassic Ziliujing Formation in the Fuxing area,eastern Sichuan Basin,further confirms the great oil and gas exploration potential of continental shale.However,the Dongyuemiao Member shale has special features such as high clay mineral content,presence of shell-rich interbeds and high thermal evolution degree of organic matter,making it a new type of continental shale.So far,the development characteristics and influence factors of its high-quality reservoirs have not been studied systematically.In this paper,the development characteristics of Dongyuemiao Member shale reservoirs are analyzed by means of XRD,thin section analysis,argon-ion polishing scanning electron microscopy,mercury injection and liquid nitrogen adsorption combined measurement,major and trace element analysis,and nano-CT comprehensively.Then,the factors controlling the development of high-quality shale reservoirs are discussed.Finally,its petroleum geological significance is clarified.The following results are obtained.First,the reservoir space in the Dongyuemiao Member continental shale exhibits the development characteristics of coexistence of pores and fractures,dominance of inorganic pores,large pores and large throats.Eight types of pores dominated by intercrystalline pore of clay mineral,and microfractures such as diagenetic contraction fracture and hydrocarbon-generation overpressured fracture are developed.The inorganic pores account for 80%–90%.The pores are mainly mesopores and macropores.The shale pore throat radius is large.The laminated shell/silty clay shale and the laminated shell clay shale are two kinds of laminated shale with good quality of source rocks,as well as the high-quality reservoirs in the Dongyuemiao Member.Second,the formation of the laminated shell clay shale reservoirs follows the mechanisms of high content of clay minerals expanding pores,high evolution degree generating pores,fracture formation at layer coupled interface,and ov

关 键 词：四川盆地东部 侏罗系 东岳庙段 陆相页岩 储层特征 主控因素 勘探启示 

分 类 号：TE122.2[石油与天然气工程—油气勘探]