内蒙古阿尔山地区南兴安侏罗纪钾长花岗岩地球化学特征及找矿意义  

Geochemical characteristics and prospecting significance of late Jurassic moyite inNanxing′an,Arxan Area of Inner Mongolia

作　　者：沈坤[1] 李亚辉[2,3] 解惠 Shen Kun;Li Yahui;Xie Hui(No.1 Geological Exploration Institute of Henan Province,Zhengzhou 450001,China;Coal Geology Bureau of Henan Province,Zhengzhou 450016,China;Henan Engineering Technology Research Center of Energy Drilling,Zhengzhou 450016,China;Department of Architectural Engineering of Luzhou Vocational and Technical College,Luzhou 646000,China)

机构地区：[1]河南省地质矿产勘查开发局第一地质勘查院,河南郑州450001 [2]河南省煤田地质局,河南郑州450016 [3]河南省能源钻井工程技术研究中心,河南郑州450016 [4]泸州职业技术学院建筑工程学院,四川泸州646000

出　　处：《能源与环保》2020年第10期79-85,91,共8页CHINA ENERGY AND ENVIRONMENTAL PROTECTION

基　　金：内蒙古兴安盟阿尔山等五幅1∶5万区域矿调项目(NMKD2006-08)。

摘　　要：内蒙古阿尔山地区南兴安晚侏罗纪钾长花岗岩体与钼、铅、锌等成矿关系密切。以阿尔山等5幅1∶5万区域地质矿产调查为基础,通过岩石学和地球化学研究,揭示该岩体成因类型及其形成的构造背景。研究表明,其具有高硅、高铝、高钾、富碱、低镁、低钛的特点,A/NK平均为1.59,A/CNK平均达到1.50,为典型的强过铝质花岗岩类。稀土总量(∑REE)及LREE富集,LREE和HREE分馏较强,强烈负Eu异常以及弱负Ce异常,富集高场强元素Zr、Hf和大离子亲石元素U、Th,亏损Ba、Sr、Ti、Pb,说明该岩体重显性比较好,显示了同源性,表现出板内和火山弧花岗岩的一些特征,可能来自于中—上部地壳部分熔融。主微量元素特征及成矿元素含量特征暗示该区钾长花岗岩具有较好的钼铅锌成矿专属性。上述结论将有助于推动内蒙古阿尔山地区成矿研究和地质找矿工作。The late Jurassic moyite in the Nanxing′an area of Inner Mongolia are closely related to molybdenum,lead and zinc mineralization.Based on the 1∶50000 regional geological and mineral survey of Arxan and other 5 sheets,the genetic type and tectonic background of the rock mass were revealed through petrological and geochemical studies.The study showed that the rock mass is characterized by high silicon,high aluminum,high potassium,rich alkali,low magnesium and low titanium.The average of A/NK is 1.59,and the average of A/CNK is 1.50.It is a typical strong peraluminous granite.Total REE and LREE are enriched,LREE and HREE fractionation are strong,strong negative Eu anomaly and weak negative Ce anomaly,enriched in high field strength elements Zr,Hf and large ion lithophile elements U and Th,and depleted in Ba,Sr,Ti and Pb,it indicated that the rock is dominant in weight and shows homology,showing some characteristics of intraplate and volcanic arc granites,which may be derived from partial melting of middle upper crust.The characteristics of major and trace elements and the content of ore-forming elements suggest that the moyite in this area has a good metallogenic specialization of molybdenum,lead and zinc.The above conclusions will be helpful to promote the metallogenic research and geological prospecting in the Arxan Area of Inner Mongolia.

关 键 词：含矿性 地球化学 钾长花岗岩 侏罗纪 南兴安 内蒙古 

分 类 号：P619.2[天文地球—矿床学]