滇黔北地区下寒武统热水沉积烃源岩发育特征  

Characteristics of the Lower Cambrian hydrothermal sedimentary source rocks in northern Yunnan and Guizhou

作　　者：程青松 石阳志 章超 王鑫 季永承 王紫瑛 CHENG Qingsong;SHI Yangzhi;ZHANG Chao;WANG Xin;JI Yongcheng;WANG Ziying

机构地区：[1]中国石油浙江油田勘探开发一体化中心

出　　处：《海相油气地质》2023年第1期55-64,共10页Marine Origin Petroleum Geology

基　　金：国家科技重大专项“昭通页岩气勘探开发示范工程”(编号:2017ZX05063);中国石油天然气集团有限公司重大现场试验项目“深层页岩气有效开采关键技术攻关与试验”(编号:2019F-13)联合资助。

摘　　要：在收集滇黔北地区寒武系筇竹寺组典型热水沉积剖面资料的基础上,通过热解、TOC、饱和烃色谱-质谱、微量元素和稀土元素等实验分析,对研究区页岩的发育特征进行了深入探究,并对现代海洋热水生物及沉积物的生物标志物组合与四川盆地寒武系和塔里木盆地寒武系出现的独特生物标志物分布特征进行了对照分析。结果表明:①滇黔北地区筇竹寺组沉积时期发育热水沉积,热水环境丰富的营养物质和强还原条件有利于生物的繁盛和沉积有机质的保存,从而有利于形成优质烃源岩。②滇黔北地区筇竹寺组广泛发育陆棚相泥页岩烃源岩,优质烃源岩的发育多与热水沉积有关,热水深水环境烃源岩的形成和保存条件更佳。热水浅水陆棚相烃源岩的有机质丰度较高,TOC在2%~5%之间;热水深水陆棚相烃源岩的有机质丰度更高,TOC在5%~10%之间甚至更高。③热水沉积烃源岩在四川、塔里木等盆地寒武系普遍存在。除了陆棚区外,深海盆地也具有发育优质烃源岩的物质基础与保存条件,也可能发育优质烃源岩。On the basis of collecting the data of typical hydrothermal sedimentary outcrops of the Cambrian Qiongzhusi Formation in the northern Yunnan and Guizhou,the development characteristics of source rocks in the study area were deeply explored through pyrolysis,TOC,saturated hydrocarbon chromatography-mass spectrometry,trace elements and rare earth elements and other experimental analysis,and the biomarker assemblages of modern marine hydrothermal organisms and sediments were compared with unique biomarker distribution characteristics of the Cambrian source rocks and generated crude oil in Sichuan Basin and Tarim Basin.The results show that:(1)Hydrothermal deposition are developed during the sedimentary period of Qiongzhusi Formation in northern Yunnan and Guizhou,and the rich nutrients and strong reduction conditions in the hot water environment are conducive to the prosperity of organisms and the preservation of sedimentary organic matter,which is conducive to the formation of high-quality source rocks.(2)Shale source rocks of continental shelf are widely developed in the Qiongzhusi Formation in the north of Yunnan and Guizhou,and the development of high-quality source rocks is mostly related to hydrothermal deposition.The formation and preservation conditions of source rocks in hot deep water environment are better.The organic matter abundance of hot shallow water shelf source rocks is high,TOC is between 2%and 5%;the abundance of organic matter in hot deep water shelf source rocks is higher,and TOC is between 5%and 10%or more than 10%.(3)The thermal evolution of the source rock of Qiongzhusi Formation in the north of Yunnan and Guizhou is high,and it is in the over-mature evolution stage,with good shale gas resource potential.The total amount of shale gas resources of South Sichuan Low-Steep Fold Belt and Weixin Depression in southern Sichuan is 6589.5×108 m3,indicating they are potential shale gas exploration zones.(4)Hydrothermal sedimentary source rocks are widespread in the Cambrian in Sichuan,Tarim and othe

关 键 词：热水沉积 烃源岩 页岩气 寒武纪 滇黔北 

分 类 号：TE122.1[石油与天然气工程—油气勘探]