ISSN 1006-3021 CN11-3474/P
Published bimonthly started in 1979
投稿时间:2022-06-25  修订日期:2022-10-05
关键词:sphalerite  Electron probes  chemical composition  evolution of ore-forming fluid  Bangbule Pb-Zn deposit  Tibet
王永强 成都理工大学 610059
王勇 成都理工大学 
唐菊兴 中国地质科学院矿产资源研究所 
贺传凯 成都理工大学 
王海勇 西藏自治区地质矿产勘查开发局第六地质大队 
闫鹏刚 西藏自治区地质矿产勘查开发局第六地质大队 
冯翼鹏 中国地质大学(北京) 
摘要点击次数: 195
全文下载次数: 0
Chemical Composition Characteristics and Geological Significance of Sphalerite in Bangbule Skarn Pb-Zn Deposit, Tibet
      The newly discovered Bangbule deposit is located in the western part of the Tibet Gangdise-Nyainqentangula Pb?Zn?Ag polymetallic metallogenic belt. Sphalerite is one of the main ore minerals of this deposit, and its chemical composition is of great significance to reveal physics-chemical conditions of mineralization and ore-forming fluids evolution. In this paper, different generations of sphalerite from the proximal and distal skarn of the Bangbule deposit have been studied in detail with microscopic observation and Electron Probe Microanalysis. Two generations of sphalerite (Sph-I, Sph-II) were distinguished with regard to their mineral associations, microscopic characteristics, and geochemical features. Sph-I mainly occurred in the proximal skarn, which is dark-red and co-exists with chalcopyrite, replace magnetite and pyrrhorite. The content of Fe is high (the Fe content of some sphalerite is more than 10 wt.%), and the Zn/Fe value is mostly less than 10. Sph-II can be subdivided into two types (Sph-IIa, Sph-IIb). Sph-IIa is brownish yellow in color and developed in both proximal and distal skarns. This generation sphalerite is usually filled in between skarn mineral grains (e g., pyroxene and garnet) and the fractures of those minerals, and the Fe content is obviously lower than that of the Sph-I. Sph-IIb is mainly developed in the distal skarn, which is light yellow and co-exist with galena and quartz, and Fe content is distinctly lower than that of the Sph-I and Sph-II. The estimation of Fe-in-Sphalerite thermometer shows that the mineralization temperatures from the Sph-I to the Sph-II (160℃~314℃, 138℃~157℃, respectively), which is consistent with the results of Zn/Fe ratios of sphalerite. Based on the above features, it is suggested that the early ore-forming fluids in the Bangbule deposit are of high temperature and rich in Fe, Mn, Cu, etc. As the temperature of ore-forming fluid decreases gradually, the content of Fe and Mn in the fluids decreases significantly. Spatially, the temperature and oxygen fugacity of the ore-forming fluid gradually decreased during the migration from northwest to southeast of the deposit, and indicating that there is potential to find distal Manto-type ore-bodies in the southeast direction of the deposit.
  查看/发表评论  下载PDF阅读器
Copyright©2008 《地球学报》编辑部 All Rights Reserved
Sponsored by:中华人民共和国自然资源部
Address:: 北京市西城区百万庄大街26号,中国地质科学院东楼317室 PostCode:100037 Tel:010-68327396 E-mail: