摘要
基于岩石薄片鉴定、X射线荧光光谱(XRF)元素扫描、微区扫描电镜矿物定量评价(QEMSCAN)、场发射扫描电镜(FE-SEM)成像等实验技术手段,对四川盆地南部泸州区块龙马溪组一段(龙一段)一亚段深层页岩的纹层类型、组合及其对储层品质的影响进行了研究。结果表明,该套页岩发育自生石英-有机质纹层、碳酸盐纹层、长英质-碳酸盐混合纹层、生物骨骸纹层、陆源石英纹层、黏土矿物纹层、黄铁矿纹层和蚀变硅质纹层8种纹层类型。根据其垂向叠置关系划分为“自生石英-有机质+碳酸盐+长英质-碳酸盐”、“自生石英-有机质+碳酸盐+生物骨骸”、“碳酸盐+黏土矿物”、“陆源石英+黏土矿物”4种纹层组合。长英质-碳酸盐混合纹层与粉砂级火山物质的搬运沉积有关,其与自生石英-有机质纹层、碳酸盐纹层相互叠加构成的“自生石英-有机质+碳酸盐+长英质-碳酸盐”纹层组合发育于龙一段一亚段1小层,表现为总有机碳含量高、自生硅质矿物和碳酸盐矿物含量高、孔隙和微裂缝发育、含气性好,为最优纹层组合。蚀变硅质纹层与火山凝灰质成分的沉降有关,局部发育于龙一段一亚段2小层的“自生石英-有机质+碳酸盐+生物骨骸”纹层组合中,为次优纹层组合。这2类纹层组合对应的页岩段为泸州区块龙一段一亚段下层系页岩气开发的“甜点层”。小规模海侵和火山活动造成龙一段一亚段6小层局部的有机质、自生硅质和碳酸盐矿物含量较高,形成“碳酸盐+黏土矿物”纹层组合,为上层系页岩气立体开发的首选“甜点层”。
Based on experimental technical methods such as thin section identification,elements scanning by X-ray fluorescence(XRF) spectrometer,quantitative evaluation of materials by scanning electron microscopy(QEMSCAN) and imagining by field emission scanning electron microscopy(FE-SEM),the paper investigates the types and combinations of deep marine shale laminae and their effects on reservoir quality in the first submember of Member 1 of Longmaxi Formation(Long 1 Member) in Luzhou block,southern Sichuan Basin.The results show that 8 types of laminae are developed in shale reservoirs,such as authigenic siliceous-organic lamina,carbonate lamina,felsic-carbonate mixed lamina,bioclastic lamina,terrestrial quartz lamina,clay mineral lamina,pyrite lamina,and altered siliceous lamina.In light of the vertical fold relationship,they are divided into four lamina combinations including “authigenic siliceous-organic matter+carbonate+felsic-carbonate”,“authigenic siliceous-organic matter+carbonate+bioclastic”,“carbonate+clay mineral”,and “terrestrial quartz+clay mineral”.The felsic-carbonate mixed lamina has relation with the transport and deposition of silty volcanic materials.As being overlayed with authigenic siliceous-organic lamina and carbonate lamina,the lamina combination of “authigenic siliceous-organic matter+carbonate+felsic-carbonate” was formed and developed in the layer 1 of first submember of Long 1 Member,characterized with high total organic carbon content,high content of siliceous and carbonate minerals,developed pores and microcracks,as well as good gas bearing properties.It is the optimal lamina combination.The altered siliceous lamina has relation with the sedimentation of volcanic tuff components,and is locally developed in the lamina combination of “authigenic siliceous-organic matter+carbonate+bioclastic” in the layer 2 of first submember of Long 1 Member,which is the suboptimal lamina combination.The shale reservoirs corresponding to these two lamina combinations is the “sweet spo
作者
武瑾
李海
杨学锋
赵圣贤
郭伟
孙玉平
刘永旸
刘兆龙
Wu Jin;Li Hai;Yang Xuefeng;Zhao Shengxian;Guo Wei;Sun Yuping;Liu Yongyang;Liu Zhaolong(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;National Energy Shale Gas Research and Development(Experiment)Center,Beijing 100083,China;Shunan Division,PetroChina Southwest Oil&Gasfield Company,Sichuan Luzhou 646001,China;Shale Gas Research Institute,PetroChina Southwest Oil&Gasfield Company,Sichuan Chengdu 610051,China)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2023年第9期1517-1531,共15页
Acta Petrolei Sinica
基金
中国石油天然气集团有限公司科技专项“页岩油气开发机理及体积开发技术研究”(2023ZZ08)资助。
关键词
深层页岩气
纹层
纹层组合
储集层特征
泸州区块
四川盆地
deep shale gas
lamina
lamina combination
reservoir characteristic
Luzhou block
Sichuan Basin
