川东地区下侏罗统凉高山组地层沉积充填特征与油气勘探方向  

Strata and Sedimentary Filling Characteristics of the Lower Jurassic Lianggaoshan Formation and Its Hydrocarbon Exploration in Eastern Sichuan Basin

作　　者：易娟子 张少敏 蔡来星 陈守春[1] 罗鑫 于吉星 罗妮娜 杨田 Yi Juanzi;Zhang Shaomin;Cai Laixing;Chen Shouchun;Luo Xin;Yu Jixing;Luo Nina;Yang Tian(Geology Institute of Chongqing Gas District,PetroChina Southwest Oil&Gas Field Company,Chongqing 401120,China;Research Institute of Exploration and Development,PetroChina Southwest Oil&Gas Field Company,Chengdu 610041,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]中国石油西南油气田分公司重庆气矿地质研究所,重庆401120 [2]中国石油西南油气田分公司勘探开发研究院,成都610041 [3]成都理工大学沉积地质研究院,成都610059

出　　处：《吉林大学学报（地球科学版）》2022年第3期795-815,共21页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(41906188);油气藏地质及开发工程国家重点实验室开放基金项目(PLC20210111);自然资源部沉积盆地与油气资源重点实验室开放基金项目(cdcgs2020003)。

摘　　要：为了明确川东地区凉高山组地层沉积充填特征,以有效指导油气勘探决策,综合利用野外露头勘测、钻井岩心观察、沉积岩石学分析和油气地质学分析等手段,在系统梳理研究区层序地层结构与沉积相类型的基础上,探讨沉积序列约束下的页岩油气、致密油气协同成藏规律.结果表明:研究区发育典型的“二分”层序地层结构,早期湖侵阶段形成凉下段三角洲前缘—前三角洲—半深湖—深湖退积式准层序组,晚期湖退阶段形成凉上段进积式准层序组并可细分为3个准层序(亚段),整体由半深湖向三角洲前缘、滨浅湖演变.凉高山组半深湖—深湖、前三角洲泥页岩与三角洲前缘水下分流河道砂体纵向叠置,可形成“自生自储、下生上储、旁生侧储”多类型源储接触关系,为凉下段页岩油气、凉上段致密砂岩油气协同成藏提供了地质基础.In order to clarify the strata and sedimentary filling characteristics of the Lower Jurassic Lianggaoshan Formation in eastern Sichuan basin,for effectively guiding the hydrocarbon exploration,this study comprehensively utilizes the research tools of outcrop survey,core observation and analysis of sedimentary petrology and petroleum geology.On the basis of systematically sorting out the stratigraphic structure and sedimentary facies in the study area,we further discuss the synergistic reservoir-forming rule between shale oil and gas and tight oil and gas under the constraints of sedimentary sequence.The results show that typical dichotomy sequence stratigraphic structure is developed in the study area.In the early lake transgression stage,the Lower Lianggaoshan Formation formed a landward stepping parasequence set,which was composed of delta front,prodelta,semi-deep lake and deep lake.In the late lake regression stage,a seaward stepping parasequence set is developed in the Upper Lianggaoshan Formation,which can be subdivided into three parasequences or subsections,showing the evolution from semi-deep lake to delta front,shore and shallow lake.The mudstones and shales of semi-deep lake,deep lake and prodelta facies are vertically superimposed with the sandstone bodies of underwater distributary channel in the delta front subfacies,forming various source-reservoir contact relationships,such as“self-generation and self-storage,lower generation and upper storage,side generation and side storage”.This provides a geological basis for the coordinated accumulation of shale oil and gas in the Lower Lianggaoshan Formation and tight oil and gas in the Upper Lianggaoshan Formation.

关 键 词：地层格架 三角洲 凉高山组 页岩油气 致密油气 川东地区 

分 类 号：P618.13[天文地球—矿床学]