金川铜镍硫化物矿床2号矿体铂族元素地球化学特征及其意义  

Geochemical characteristics and significance of platinum group elements in No.2 ore body of Jinchuan Cu-Ni sulfide deposit

作　　者：华照福 陆继龙[1] 侯亚茹 赵威 李超 孙小涵 HUA Zhaofu;LU Jilong;HOU Yaru;ZHAO Wei;LI Chao;SUN Xiaohan(College of Geo-Exploration Science and Technology,Jilin University,Changchun 130026,China)

机构地区：[1]吉林大学地球探测科学与技术学院,长春130026

出　　处：《世界地质》2024年第2期216-227,共12页World Geology

基　　金：重点研发计划项目(2021YFC2901801,2016YFC0600606)。

摘　　要：以金川铜镍硫化物矿床2号矿体为研究对象,开展了主量元素、微量元素以及铂族元素(PGE)地球化学特征研究,探讨金川矿床岩浆演化和成矿机制。结果显示,研究区岩矿石(La/Yb)_(N)值为4.1,富集轻稀土;(La/Lu)_(N)值为3.8,轻重稀土分馏;亏损高场强元素Nb、Th和Zr,表明矿体形成过程中存在地壳混染。2号矿体矿石中PGE总量高于岩石,是由于矿化作用导致PGE发生富集。岩矿石中存在PGE分异,主要富集低熔点组PGE(Rh、Pt、Pd)。基于研究结果,推测研究区母岩浆为地幔中等部分熔融形成的玄武质岩浆,主要成矿机制是深部熔离--贯入机制。Taking No.2 ore body of Jinchuan Cu-Ni sulfide deposit as the research object,the geochemical characteristics of major elements,trace elements and platinum group elements(PGE)were studied to explore the magma evolution and metallogenic mechanism of Jinchuan deposit.The results show that the(La/Yb)_(N) value of rock and ore in the study area is 4.1,enriched in LREE;the(La/Lu)_(N) value is 3.8,fractionated in LREE and HREE;and depleted in high field-strength elements Nb,Th and Zr,indicating that there is crustal contamination in the formation process of the ore body.The content of PGE in ore of No.2 ore body is higher than that in rock,which is due to the enrichment of PGE caused by mineralization.There is PGE differentiation in the rock and ore,mainly enriched in low melting point PGE(Rh,Pt,Pd).Based on the research results,it is inferred that the parent magma in the study area is basaltic magma formed by moderately partial melting of the mantle,and the main metallogenic mechanism is deep liquation and injection.

关 键 词：铜镍硫化物 铂族元素 地球化学特征 金川矿床 

分 类 号：P595[天文地球—地球化学] P618.2[天文地球—地质学]