地质科技情报2018，Vol.37Issue(1)：7-15,9.DOI:10.19509/j.cnki.dzkq.2018.0102
内蒙古白云鄂博群地层岩石地球化学:对浩尧尔忽洞金矿床层控机理研究
Petrology, Geochemistry and Pb Isotope Composition of Bayan Obo Group in Inner Mongolia:Constraints on the Genesis of Stratabound Haoyaoerhudong Gold Deposit
摘要
Abstract
There are many large and super-large gold deposits and spots in the Northern China Craton (NCC),which are hosted by black shales.However,there is currently no model for the role of marine sedimentary rocks in contact with gold deposits.In this paper,we present the results of the petrology,geochemistry and Pb isotope composition of Bayan Obo Group,and discuss the mechanism of Haoyaoerhudong gold ore bodies controlled by strata.There are many abrupt lithologic changes and carbon in the first and second lithologic sections of Bilute Formation,the main host rocks for gold orebodies in the study area.The ore,Bilute Formation and Hercynian magma rocks generally have a similar trace and REE elements variation trend such as the enrichment of La,Sm,Y,and LREE,and the depletion of Nd,Ta,Sr,Zr,Hf,and HREE.The star-like pyrite in carbonaceous slate of Bilute Formation and sulfide in ore have a similar Pb isotope composition,with the ranges of 208Pb/204Pb,207Pb/ 204Pb,and 206Pb/204Pb varying from 38.960 0 to 38.982 9,15.643 5 to 15.684 2 and 18.566 0 to 18.921 7,respectively.These geological-geochemical characteristics indicate that ore-forming materials mainly come from the strata.On the one hand,the Caledonian regional compression deformation,large scale Hercynian magma intrusion and Hercynian-Indochina brittle-ductile shearing cooperated to make Au to active and migrate,and on the other hand,this cooperation provided better space for fluxion and emplacement of ore-forming fluids.And the carbon in Bilute Formation is better reductant for precipitation of Au in Haoyaoerhudong gold deposit.关键词
浩尧尔忽洞金矿床/白云鄂博群/比鲁特组/星点状黄铁矿/Pb同位素Key words
Haoyaoerhudong gold deposit/Bayan Obo Group/Bilute Formation/star-like pyrite/Pb isotope分类
天文与地球科学引用本文复制引用
孙亮,张林,张海东..内蒙古白云鄂博群地层岩石地球化学:对浩尧尔忽洞金矿床层控机理研究[J].地质科技情报,2018,37(1):7-15,9.基金项目
国家自然科学基金项目(41402042) （41402042）
中国地质调查局项目(12120114021001) （12120114021001）
