滇西勐兴铅锌矿床闪锌矿ICP-MS微量元素特征及其地质意义  

The ICP-MS Trace Element Characteristics of Sphalerites from the Mengxing Pb-Zn Deposit,Western Yunnan and their Geological Significances

作　　者：刘锦康 邓明国[1] 李余华 刘阳[1] LIU Jin-kang;DENG Ming-guo;LI Yu-hua;LIU Yang(Faculty of Land Resource Engineering,Kunming University of Science and Technology,Kunming 650093,China;Geological Team 209,Yunnan Nuclear Industry,Kunming 650032,China)

机构地区：[1]昆明理工大学国土资源工程学院,昆明650093 [2]云南省核工业二○九地质大队,昆明650032

出　　处：《矿物岩石地球化学通报》2020年第1期133-143,共11页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家自然科学基金资助项目(41363001,41762009)。

摘　　要：勐兴铅锌矿床是滇西保山地块内迄今勘查程度最高的大型铅锌矿床。由于该矿床的研究程度相对较低,其成因认识存在较大争议。本文使用ICP-MS对该矿床中主要矿石矿物闪锌矿进行了微量元素分析,以探讨该矿床的成矿作用。结果表明,该矿床各阶段闪锌矿的颜色、Fe和Mn含量及Ge/In值特征指示矿床的成矿流体温度不高,可能为与低温盆地流体有关的铅锌矿床。此外,闪锌矿以ΣREE较低、LREE/HREE值大和δEu值小为特征,暗示闪锌矿形成于亏损Eu的还原性流体。结合矿床地质特征、闪锌矿微量元素特征及lnGa-lnIn关系判别图解认为,勐兴铅锌矿床属于密西西比河谷型铅锌矿床(MVT型)。The Mengxing Pb-Zn deposit,located in the Baoshan Block in western Yunnan,is a large-scale Pb-Zn deposit with the highest level of exploration so far in the area.Due to the low degree of research,however,there is a great dispute in the ore genesis.Trace elements in the sphalerite,the main ore mineral,have been analyzed by using ICP-MS to discuss the metallogenesis of the deposit in this paper.The results show that the colors,Fe and Mn contents,and Ge/In ratios of sphalerites of various stages suggest that the temperature of ore-forming fluid is not high and formation of the deposit could be related to the low temperature basin fluid.In addition,the sphalerites are characterized with low REE abundances,high LREE/HREE ratios,and lowδEu values,implying that the sphalerite was formed in Eu-depleted reduced fluid.Combining with geological features of the deposit,characteristics of trace elements of sphalerites,and the lnGa-lnIn discriminant diagram for sphalerites,it is believed that the Mengxing Pb-Zn deposit belongs to the MVT-type one.

关 键 词：闪锌矿 微量元素 MVT矿床 勐兴铅锌矿床 滇西 

分 类 号：P618.43[天文地球—矿床学]