摘要
氦源岩的生氦潜力是决定氦气资源形成的首要条件,地壳中富含铀、钍的花岗岩、富有机质页岩等均是良好的氦源岩。该研究针对柴达木盆地北缘开展了野外地质调查和钻井岩心观察,综合前人研究资料系统梳理了区内不同地层单元的元素地球化学和年代学数据,研究了柴北缘主要氦源岩地球化学特征及其生氦潜力。研究结果表明:基底型氦源岩古元古代达肯大坂岩群片麻岩—麻粒岩与其上叠加的早古生代滩间山群浅变质岩系生氦强度分别为0.565×10^(-12)cm^(3)/(a·g)和0.278×10^(-12)cm^(3)/(a·g)。海西期和印支期侵入岩体及火山岩,呈山体分布于盆地边缘,玄武岩、安山岩类生氦强度分别为0.198×10^(-12)cm^(3)/(a·g)和0.623×10^(-12)cm^(3)/(a·g);花岗岩类生氦强度分别为0.217×10^(-12)cm^(3)/(a·g)和0.348×10^(-12)cm^(3)/(a·g)。柴北缘主要沉积型氦源岩为石炭系海相沉积和侏罗系陆相地层,具有较高的铀、钍含量。石炭系在柴北缘广泛分布,上石炭统泥页岩U和Th平均丰度分别为8.70×10^(-6)和15.10×10^(-6),生氦强度为1.483×10^(-12)cm^(3)/(a·g)。中、下侏罗统泥页岩层系沿阿尔金山和柴北缘断续分布,U和Th平均丰度分别为7.72×10^(-6)和20.21×10^(-6),生氦强度为1.509×10^(-12)cm^(3)/(a·g)。整体上,柴达木盆地北缘发育多类型多层系氦源岩,具有广阔的资源前景。该研究为柴达木盆地氦气资源综合调查提供了基础数据。
Helium generating potential of helium source rocks act as the primary element in generating helium resources.Organic-rich shales and granites in the crust rich in uranium and thorium are good helium source rocks.Based on field geological surveys and core observations in the northern margin of Qaidam Basin,combined analysis of systematic element geochemistry and chronology data of different stratigraphic units in the area,this study investigated geochemical characteristics and heliumgenerating potential of the main helium source rock types in the Northern Qaidam Basin.The results show that the helium source rocks of the basement type of the Paleoproterozoic Dakendaban Group and the Early Paleozoic Tanjianshan Group display helium-generating intensity of 0.565×10^(-12)cm^(3)/(a·g)and 0.278×10^(-12)cm^(3)/(a·g),respectively.Hercynian and Indosinian intrusive rocks and volcanic rocks occur in the basin margin.The helium-generating intensity of Hercynian and Indosinian volcanic rocks are 0.198×10^(-12)cm^(3)/(a·g)and 0.623×10^(-12)cm^(3)/(a·g),while the Hercynian and Indosinian intrusive rocks show helium-generating intensity of 0.217×10^(-12)cm^(3)/(a·g)and 0.348×10^(-12)cm^(3)/(a·g),respectively.The main sedimentary helium source rocks in the northern margin of the Qaidam Basin are Carboniferous marine deposits and Jurassic continental strata with high uranium and thorium content.The Carboniferous series is widely distributed in the northern margin of Qaidam Basin and exhibits average abundance of U and Th of 8.70×10^(-6) and 15.10×10^(-6),respectively,and a helium-generating intensity of 1.483×10^(-12)cm^(3)/(a·g).The middle and lower Jurassic shale series occur intermittently along the Altun Mountain and Qaidam margins,displaying average abundance of U and Th of 7.72×10^(-6) and 20.21×10^(-6),respectively,and a helium-generating intensity of 1.509×10^(-12)cm^(3)/(a·g).Overall,this study lays a foundation for comprehensive helium resource geological surveys in the Qaidam Basin.
作者
杨元元
殷万熹
强晓农
马永福
刘清
马寅生
胡俊杰
施辉
YANG Yuanyuan;YIN Wanxi;QIANG Xiaonong;MA Yongfu;LIU Qing;MA Yinsheng;HU Junjie;SHI Hui(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;Key Laboratory of Paleomagnetism and Tectonic Reconstruction,Ministry of Natural Resource,Beijing 100081,China;Key Laboratory of Petroleum Geomechanics,China Geological Survey,Beijing 100081,China;Haixi Natural Resources Bureau,Delingha 817000,China;QingHai Branch of China National Geological Exploration Center of Building Materials Industry,Xining 810008,China)
出处
《高校地质学报》
北大核心
2025年第4期432-438,共7页
Geological Journal of China Universities
基金
中国地质调查局地质调查项目(DD20242211,DD20230297)
青海省“昆仑英才”行动计划(QHKLYC-GDCXCY-2021-465)
海西州“柴达木英才·生态资源科技人才”计划及院所长基金项目(JKYQN202410)联合资助。
关键词
柴达木盆地北缘
氦源岩
生氦潜力
岩浆岩
元素地球化学
Northern Qaidam Basin
Helium source rock
Helium-producing potential
Igneous rocs
Geochemistry of elements
作者简介
杨元元,女,1985年生,副研究员,主要从事油气地球化学研究工作,E-mail:2530887384@qq.com;通讯作者:胡俊杰,男,1987年生,副研究员,主要从事沉积演化和古气候变化研究工作,E-mail:howimet@foxmail.com;通讯作者:施辉,男,1983年生,副研究员,主要从事油气地质及成藏机理研究工作,E-mail:shui@mail.cgs.gov.cn。
