东昆仑卧龙岗锑矿痕量元素示踪及成因分析

新疆东昆仑卧龙岗一带存在多个中、大型锑矿床,为了解该锑矿富集区的物质来源,探讨其成矿机制,通过系统的野外地质调查,总结矿床地质成矿条件基础上,对矿区典型的矿石、石英脉及围岩进行了微量元素和稀土元素分析。结果表明:矿石、石英脉及围岩均具有轻稀土富集、分馏程度高、重稀土亏损的特点;锑矿石中Eu为无铕异常,Eu平坦型,Ce中度负异常,反映出成矿流体基本属于中性环境,矿体和围岩的稀土元素具有同源性;矿石、石英脉及围岩的微量元素特点相似,表明矿体和围岩的微量元素来源相同;围岩和石英脉展示出的轻稀土富集、重稀土亏损和Eu、Ce负异常的稀土配分模式与上部地壳的稀土配分模式十分相似,表明围岩中的稀土元素迁出很少,成矿流体对围岩稀土元素的组成影响很小,说明矿脉中的REE主要来源于上部地壳,赋矿围岩的贡献不大;成矿流体沿近北东-南西向断裂充填,矿床成因类型属于浅成热液充填型锑矿床。

Rare Earth Element and Trace Element Geochemistry of Wolonggang Antimony Enrichment Area Deposit and Its Tracing Significance for the Origin of Metallogenic Elements in Dongkunlun

Combined with system field investigation and ore-forming geological conditions of the Huangyangling antimony deposit, the geochemical characteristics of the deposit are summarized, the origin of the ore-forming materials is ascertained, and ore-forming mechanisms is discussed according to the major element analysis and trace element analysis.The results show that the Eu has no Eu anomalies and performing Eu flat-type, moderate depletion of Ce.This reflects that ore-forming fluid basically belongs to neutral environment and original hydrothermal depletes Ce in the ore-forming fluid.There are characteristics of enrichment of LREE, depletion of HREE and nega-tive anomaly of Ce, which shows that the orebody and the surrounding rock are homologous.REE distribution patterns performed by the surrounding rock and quartz are very similar to the upper crust, which reflects that the REE moves little in surrounding rock and the effect of the ore-form-ing fluid to surrounding rock is very small.That explants that REE of the ore vein mainly comes from deep crust and the contribution ofhost rock is small.Compared with the REE distribution pat-tern of hydrothermal fluid of the submarine and spout-sediment deposit, Huangyangling antimony deposit is obviously different, which the metallogenic material mainly comes from the deep crust and the ore genesis of it belongs to post magmatic hydrothermal typeof antimony deposit.