滇西保山地块金厂河铁铜铅锌多金属矿床硫铅同位素特征与成矿物质来源示踪  

S-Pb isotope characteristics and source tracing of ore-forming materials in the Jinchanghe Fe-Cu-Pb-Zn polymetallic deposit, Baoshan block, western Yunnan Province

作　　者：李振焕 李文昌[1,2] 刘学龙[1,3] 张娜 朱俊[1,3] 陈建航[1] 张昌振 罗应 LI Zhenhuan;LI Wenchang;LIU Xuelong;ZHANG Na;ZHU Jun;CHEN Jianhang;ZHANG Changzhen;LUO Ying(College of Land and Resources Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China;Chengdu Geological Survey Center of China Geological Survey,Chengdu 610081,Sichuan,China;Key Laboratory of Sanjiang Mineralization and Resource Exploration and Utilization,MNR,Kunming 650051,Yunnan,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]中国地质调查局成都地质调查中心,四川成都610081 [3]自然资源部三江成矿作用及资源勘查利用重点实验室,云南昆明650051

出　　处：《地质通报》2020年第4期552-562,共11页Geological Bulletin of China

基　　金：云南省科学技术奖-杰出贡献奖项目《西南三江复合成矿作用研究》(编号:2017001)、云南省基础研究计划项目《滇西北中甸铜厂沟燕山期斑岩型Mo-Cu矿床热液蚀变分带与成矿流体研究》(编号:2019FB062);云南省基础研究计划重点项目《滇西格咱斑岩铜钼矿带多期复合成矿作用研究》(编号:2019FA018);云南省万人计划"青年拔尖人才"项目(编号:109720190028);昆明理工大学地质资源与地质工程省级一流学科建设项目(编号:1407839305)。

摘　　要：滇西金厂河铁铜铅锌多金属矿床位于保山地块北部,是"三江"多金属成矿带内典型矿床之一。对该矿床开展硫铅同位素示踪研究,探讨成矿物质来源,并结合构造背景和成矿时代分析了矿床成矿机制。样品测试结果表明,矿石中硫化物的δ34S值为+2.5‰^+11.1‰,平均值为+5.65‰,硫同位素来源为深部幔源岩浆和岩浆上侵混染壳源物质形成的多种硫源同位素组合;矿石矿物铅同位素组成中206Pb/204Pb为18.167~18.497,207Pb/204Pb为15.668~15.779,208Pb/204Pb为38.554~38.997,铅同位素总体较稳定,显示壳幔混染特征,以上地壳铅为主,可能来源有深部侵入岩浆及赋矿围岩。由矿床成矿物质来源表现出的多源、深源-浅源的特征推测,与成矿有关的中酸性岩体隐伏在区域深部。The Jinchanghe Fe-Cu-Pb-Zn polymetallic deposit in western Yunnan is located in the northern part of Baoshan block, and is one of the typical deposits in the Sanjiang polymetallic metallogenic belt.In this paper, the S-Pb isotope tracer study was carried out to explore the source of ore-forming materials, and the metallogenic mechanism of the deposit was summarized and studied in combination with the tectonic setting and metallogenic age.The results of sample testing show that the value of the δ34S in the ore is +2.5‰^+11.1‰, and the average value is +5.65‰. The S isotope source is a variety of S isotope assemblages formed by deep mantle-derived magma and crust-derived material contaminated by magma.The Pb isotope compositions of ore minerals are 206Pb/204Pb 18.167~18.497, 207Pb/204Pb 15.668~15.779, and 208Pb/204Pb 38.554~38.997.The Pb isotopes are generally stable, indicating that the contamination of crust and mantle was dominated by lead in the upper crust, possibly from deep intrusive magma and ore-bearing Cambrian strata.The deposit characteristics of composite mineral sources show an inferred multi-source, deep source shallow source, and the mineralization of the acidic rock should be buried in the depth.

关 键 词：滇西 金厂河 多金属矿床 硫铅同位素 成矿物质来源 成矿机制 

分 类 号：P597[天文地球—地球化学] P618.31[天文地球—地质学]