川北地区大安寨段页岩油气源、储特征及富集层段优选  

Source and reservoir characteristics as well as optimization of favorable shale oil and gas enrichment intervals of the Da\anzhai Member in northern Sichuan

作　　者：刘忠宝 李倩文[1,2,3] 刘光祥 李鹏[3] 陈斐然[4] 郝景宇[4] 张文涛[5] LIU Zhongbao;LI Qianwen;LIU Guangxiang;LI Peng;CHEN Feiran;HAO Jingyu;ZHANG Wentao(State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development,Beijing 100083,China;Sinopec Key Laboratory of Shale Oil/Gas Eaploration and Production Technology,Beijing 100083,China;Sinopec Petroleum Exploration and Production Research Institute,Beijing 100083,China;Southern Company of Erploration,Sinopec,Chengdu,Sichuan 61004l,China;Wuri Research Institute of Petroleum Geology,Sinopec Petroleum Exploration&Production Research Institute,Wuri,Jiangsu 214126,China)

机构地区：[1]页岩油气富集机理与高效开发全国重点实验室,北京100083 [2]中国石化页岩油气勘探开发重点实验室,北京100083 [3]中国石化石油勘探开发研究院,北京100083 [4]中国石化勘探分公司,四川成都610041 [5]中国石化石油勘探开发研究院无锡石油地质研究所,江苏无锡214126

出　　处：《地质学报》2023年第10期3421-3437,共17页Acta Geologica Sinica

基　　金：国家科技重大专项课题(编号2017ZX05036004);中国石油化工股份有限公司技术开发项目(编号P19017-2)资助的成果。

摘　　要：为查明川北地区大安寨段页岩油气烃源、储集特征及富集有利层段,以岩芯观察描述为基础,以岩石学与矿物学、有机地球化学及页岩储层表征等理论方法与技术为指导,开展了大安寨段二亚段纵向上4个小层岩相、烃源、储集特征的精细表征与差异性对比研究,优选出了页岩油气富集有利层段,并提出勘探研究建议。研究结果表明:大安寨段二亚段富含(泥质)介壳灰岩、(泥质纹层状)粉细砂岩2种夹层,低—中碳黏土质页岩、中碳纹层—薄层状介壳页岩、低碳(纹层状)粉砂质页岩、低碳粉砂质介壳灰质页岩4种页岩岩相;(2)小层以中碳黏土质页岩、中碳纹层状介壳页岩为主,夹层相对少,页岩连续性较好;而(4)小层以中碳纹层状介壳页岩夹介壳灰岩为主,不同尺度介壳灰岩夹层多。页岩有机显微组分整体以镜质组为主,(2)、(4)小层固体沥青较发育,自下而上有机质类型发生6次变化,依次为Ⅲ—Ⅱ2—Ⅲ—Ⅱ_(2)—Ⅱ1—Ⅱ_(2);(2)小层与(4)小层生油气能力相对较好,(4)小层略好于(2)小层。页岩储集物性明显好于夹层,(2)小层和(4)小层页岩生烃能力相对好,有机质孔较发育,含气量相对高,页岩烃源—储集—含(油)气性匹配关系相对好,评价认为大安寨段二亚段上部(4)小层纹层状介壳页岩段为最佳页岩油气富集层段,其次为下部(2)小层黏土质页岩层段。基于研究区大安寨段二亚段沉积非均质性强、含油气性好的层段时空分布不稳定的特点,建议重视砂、泥、灰混积差异,加强以小层为单元的岩相(组合)时空分布规律研究;重视保存条件与含气性差异,加强常规—非常规一体油气勘探选区、选层研究。To find out the source and reservoir characteristics as well as favorable shale oil&gas enrichment intervals of the Da\anzhai Member in northern Sichuan,fine characterization and contrastive studies of lithofacies,source and reservoir characteristics aimed at the four sublayers of the second section of the Da\anzhai Member(hereinafter referred to as the J1da 2)were carried out.It was based on core observation and description,guided by theoretical methods and technologies such as petrology and mineralogy,organic geochemistry and shale reservoir characterization.Then favorable intervals of shale oil and gas enrichment in vertical section were selected,and further exploration recommendation was proposed.Results suggest that:①two interlayers are developed in J1da 2,that is,(argillaceous)shell limestone and(argillaceous laminated)siltstone.Four shale lithofacies types are identified,including low-medium-TOC clayey shale,medium-TOC lamellar-thin shell shale,low-TOC(laminated)silty shale and low-TOC silty shell calcareous shale.The 2nd sublayer is mainly consisting of medium-TOC clayey shale lithofacies and medium-TOC lamellar shell shale lithofacies,with relatively few interlayers and good shale continuity.However,the 4th sublayer primarily contains medium-TOC lamellar shell shale lithofacies,interbedded with shell limestone interlayers in different scales.②The organic macerals of J1da 2 shale are mainly vitrinite.Solid asphalts are more developed in the 2nd and 4th sublayers.From bottom to top,organic matter types have changed six times,which areⅢ-Ⅱ_(2)-Ⅲ-Ⅱ_(2)-Ⅱ1-Ⅱ_(2)in turn.For the hydrocarbon generation capacity of J1da 2 shale,the 2nd and 4th sublayers are relatively better than the others,and the 4th sublayer is slightly better than the 2nd sublayer.③Physical properties of J1da 2 shale are obviously better than that of interlayers.Due to better hydrocarbon generation capacity,organic pores of the 2nd and 4th sublayers are more developed and the gas contents are relatively higher.Hence,the match

关 键 词：陆相页岩油气 有机质类型 有机质孔 源-储特征 大安寨段 侏罗系 

分 类 号：P618.13[天文地球—矿床学]