欢迎访问现代地质!

现代地质 ›› 2011, Vol. 25 ›› Issue (5): 853-860.

• 矿床学与岩石学 • 上一篇    下一篇

藏南拉木由塔锑(金)矿床S、Pb同位素组成及指示意义

杜泽忠1,顾雪祥1,李关清1,2,章永梅1,程文斌1,景亮兵3,张兴国2   

  1. 1中国地质大学 地质过程与矿产资源国家重点实验室,北京100083;2西藏自治区地质矿产勘查开发局 区域地质调查大队,
    西藏 拉萨851400; 3中色金地资源科技有限公司,北京100012
  • 收稿日期:2011-03-23 修回日期:2011-06-06 出版日期:2011-10-26 发布日期:2011-11-03
  • 通讯作者: 顾雪祥,男,教授,博士生导师,1963年出生,矿物学、岩石学、矿床学专业,主要从事矿床学和矿床地球化学的研究工作。Email:xuexianggu@cugb.edu.cn。
  • 作者简介:杜泽忠,男,博士研究生,1986年出生,矿物学、岩石学、矿床学专业,主要从事矿床学和矿床地球化学的研究。Email:27793009@qq.com。
  • 基金资助:

    中国地质调查局西藏自治区矿产资源潜力评价项目(1212010813025);中国地质大学(北京)基本科研业务费专项资金项目(2011PY0164)。

Sulfur, Lead Isotope Composition Characteristics and the Relevant Instructive Significance of the Lamuyouta Sb(Au) Deposit, South Tibet

 DU  Ze-Zhong-1, GU  Xue-Xiang-1, LI  Guan-Qing-1, 2 , ZHANG  Yong-Mei-1, CHENG  Wen-Bin-1, JING  Liang-Bing-3, ZHANG  Xin-Guo-2   

  1. 1State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing100083, China;
    2 Regional Geological Survey Party of Tibet Bureau of Geology and Exploration, Lhasa,Tibet851400, China;
    3Beijing Donia Resources Co Ltd, Beijing100012, China
  • Received:2011-03-23 Revised:2011-06-06 Online:2011-10-26 Published:2011-11-03

摘要:

西藏拉木由塔锑(金)矿床位于藏南Sb-Au成矿带东段,矿(化)体主要赋存于中侏罗统遮拉组地层与辉绿(玢)岩脉接触带上。在分析该矿床成矿地质条件的基础上,系统研究了矿石硫、铅同位素组成特征,并通过与区域成矿带中典型矿床硫、铅同位素组成的对比分析,探讨了矿床成矿物质来源。研究表明矿石硫化物的硫同位素组成变化范围较窄,成矿热液δ34SΣS在0值附近,与藏南Sb-Au成矿带中典型矿床的δ34S值相似,反映其来源与岩浆硫密切相关。矿石铅同位素组成变化范围较大,为异常铅,且构成了铅二次等时线,求得放射性成因铅源区年龄为1 638 Ma,反演了矿石铅的两阶段演化过程,推断其来源于上地壳古陆结晶基底,该研究成果能为藏南特提斯喜马拉雅锑金成矿带的研究提供一定的帮助。

关键词: 同位素组成, 成矿物质来源, 锑(金)矿床, 拉木由塔, 西藏

Abstract:

Lamuyouta Sb (Au) deposit is located in the eastern section of SbAu metallogenic belt, south Tibet The ore body mainly occurs at the contact between the strata of the Middle Jurassic Zhala Formation and diabase (allgovite) veins. Based on the analysis of geological and oreforming conditions, this paper systematically focuses on the composition characteristics of S, Pb isotopes in the sulfide ore minerals, as well as a comparison of S, Pb isotope composition among other typical ore deposits developed in the same regional metallogenic belt. In addition, it also discusses the sources of the oreforming materials. Studies have shown that the composition of S isotope in sulfide ore minerals has a narrow variation range and the δ34SΣS in the oreforming hydrothermal system is about 0, which is similar to other typical ore deposits developed in regional metallogenic belt, south Tibet. It is estimated that the sulfur origin is closely related to the magmatic sulfur. The isotopic composition of ore lead is varied greatly and belongs to anomalous lead, which constitutes a secondary isochron of lead. And then, it is calculated that the age about the lead with radiogenic source is 1,638 Ma, which inverts twostage evolution process of ore lead. Therefore, it is speculated that they sourced from ancient crystalline basement of upper continental crust, in order to provide some help for the study of HimalayanTethyan antimonygold metallogenic belt in Tibet.

Key words: isotopic composition, source of oreforming materials, sb (Au) deposit, Lamuyouta, Tibet