自然科学版 英文版
自然科学版 英文版
自然科学版 英文版
自然科学版 英文版
英文版编委
自然科学版 英文版
英文版首届青年编委

您目前所在的位置:首页 - 期刊简介 - 详细页面

中南大学学报(英文版)

Journal of Central South University

Vol. 27    No. 1    January 2020

[PDF Download]    [Flash Online]

    

Order of sphalerite and galena precipitation: A case study from lead-zinc deposits in southwest China
ZHANG Yan(张艳)1, HAN Run-sheng(韩润生)1, WEI Ping-tang(魏平堂)2

1. Kunming University of Science and Technology, Southwest of Geological Survey, Geological Survey Center for Non-ferrous Mineral Resources, Kunming 650093, China;
2. Kunming Geological Prospecting Institute, China Metallurgical Geological Bureau,
Kunming 650024, China

Abstract:Most of the lead and zinc deposits in Southwest China, are characterized by mineral zoning, which is especially true for the Huize and Zhaotong deposits. The mineral assemblage zoning is consistent for both horizontal and vertical zoning, from the base (center) of the ore body to the top (outermost), the mineral zones are as follows. I-1: coarse-grained pyrite and a little puce sphalerite; I-2: brown sphalerite, galena, and ferro-dolomite; I-3: galena, sandy beige and pale yellow sphalerite, and calcite; and I-4: fine-grained pyrite, dolomite, and calcite. Among them, sphalerite is the landmark mineral of different zoning. From I-1 to I-3, the color of sphalerite changes from dark to light, its crystalline size changes from coarse to fine, and its structure changes from disseminated to veinlet. This mineral zoning is seen not only on a microscopic scale, but is also clear on a mesoscopic and macroscopic scale. It is caused by the order of the sphalerite and galena precipitation. We studied the metallic minerals and fluid inclusions using a thermodynamic phase diagram method, such as lgfO2–lgfS2, pH–lgfO2, pH–lg[Pb2+] and pH–lg[HS-], discussed the constraints on the order of the sphalerite and galena precipitation in the migration and precipitation process of lead and zinc under different pH values, oxygen fugacity, sulfur fugacity, and ionic activity. We also explain the formation mechanism and propose that the main controlling factor of the order of the sphalerite and galena precipitation is sulfur fugacity.

 

Key words: precipitation order; thermodynamic phase diagram; mineral zoning; lead and zinc deposit; southwest of China

中南大学学报(自然科学版)
  ISSN 1672-7207
CN 43-1426/N
ZDXZAC
中南大学学报(英文版)
  ISSN 2095-2899
CN 43-1516/TB
JCSTFT
版权所有:《中南大学学报(自然科学版、英文版)》编辑部
地 址:湖南省长沙市中南大学 邮编: 410083
电 话: 0731-88879765(中) 88836963(英) 传真: 0731-88877727
电子邮箱:zngdxb@csu.edu.cn 湘ICP备09001153号