摘要
筲箕湾铅锌矿床位于扬子地块西南缘川滇黔相邻铅锌矿集区黔西北铅锌成矿区垭都―蟒硐断裂带,是贵州省有色金属及核工业地质勘探局近年发现的中型矿床。对该矿床原生矿体中主要矿石矿物黄铁矿、方铅矿和闪锌矿进行了Pb同位素组成分析,结果表明矿床Pb同位素组成变化不大,其中206Pb/204Pb、207Pb/204Pb和208 Pb/204 Pb的分布范围分别在18.616～18.686、15.682～15.728和39.067～39.181之间,在206 Pb/204 Pb-207 Pb/204 Pb和206 Pb/204 Pb-208 Pb/204 Pb图中,样品投影在上地壳铅平均演化线附近的狭小区域和区域基底岩石的Pb同位素组成范围之内,靠近不同时代碳酸盐地层以及川滇黔相邻矿集区滇东北成矿区会泽超大型铅锌矿床和黔西北成矿区天桥铅锌矿床,与震旦纪灯影组白云岩和峨眉山玄武岩分布范围存在明显差异。推测矿床成矿物质来源以基底岩石为主,区域上不同时代碳酸盐地层可能提供了部分成矿物质。
The Shaojiwan Pb-Zn deposit,in northwest Guizhou Province,China,is a medium-sized deposit in the Yadu-Mangdong metallogenic belt of the NW-Guizhou mineralization district in the Sichuan-Yunnan-Guizhou Pb-Zn ore concentration area discovered in recent years.Previous studies on geology and geochemistry of deposit are limited and mineral prediction and metallogenic mechanism are severely restricted.In this paper,we report the Pb isotopic compositions of major ore minerals incluing pyrite,sphalerite and galena from primary ore body and discuss the source of metallogenic materials.The results showed that Pb isotopic compositions are stable and the values of 206Pb/204Pb,207Pb/204Pb and 208Pb/204Pb range from 18.616 to 18.686,15.682 to 15.728 and 39.067 to 39.181,respectively.In the figures of 206Pb/204Pb vs.207Pb/204Pb and 206Pb/204Pb vs.208Pb/204Pb,all samples plot in a small area near the upper crust lead average trendline and in range of Pb isotopic compositions of the base rock in region.They are close to carbonate strata and the Huize world-class Pb-Zn deposit in NE-Yunnan mineralization district and the Tianqiao Pb-Zn deposit in the NW-Guizhou mineralization district,existing different from the range of dolomite of Sinian Dengying Formation and Emeishan Basalt.We suggest that the metallogenic materials in the Shaojiwan Pb-Zn deposit are mainly from the base rock in region and partly from carbonate strata in the region.
出处
《矿物学报》
CAS
CSCD
北大核心
2012年第2期294-299,共6页
Acta Mineralogica Sinica
基金
中国科学院重要方向项目(KZCX2-YW-Q04-05),中国科学院地球化学研究所矿床地球化学国家重点实验室提供了研究经费
国家“973”计划项目(2007CB411402)
关键词
PB同位素
成矿物质来源
筲箕湾铅锌矿床
中国黔西北
Pb
isotopic composition
metallogenic material
Shaojiwan Pb-Zn deposit
Guizhou Province
China
