西藏搭格架热泉型铯矿床地球化学  

Geochemistry of Targejia hot spring type cesium deposit in Tibet

作　　者：赵元艺[1] 聂凤军[1] 侯增谦[2] 李振清[1] 赵希涛[3] 马志邦[3] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]中国地质科学院地质研究所,北京100037 [3]中国科学院地质与地球物理研究所,北京100029

出　　处：《矿床地质》2007年第2期163-174,共12页Mineral Deposits

基　　金：国家重点基础研究发展规划973项目"印度-亚洲大陆主碰撞带成矿作用"(编号2002CB412606);国家自然科学基金项目(40302028)的联合资助

摘　　要：文章系统研究了搭格架热泉型铯矿床的气体、水体和泉华的地球化学特征。结果表明:热泉气体为典型的CO2型气体;泉水以CO23--Na型水体(pH=8.5)为主,但也出现SO42--Na型水体(pH=4.0),这两种类型泉水的Cs含量均达到工业标准,为液体Cs矿。硅华的地球化学图解综合反映出其以热水成因为主,生物成因为次的复合特点。该矿床的第2、5阶段为铯的主要成矿期,其Al/Fe、Si/Al、ΣREE、ΣLREE/ΣHREE、La页岩/Ce页岩、Eu/Eu*和U/Th与其余3个阶段的不同,深入研究结果表明这2个阶段的成矿物质铯以热水提供的为主,围岩提供的较少。The Targejia hot spring geyserite cesium deposit, located in Ang Ren County of Xigaze district in Tibet, remains very active now. This geyserite cesium deposit is rare in size in China, whose cesium reserves have reached the superlarge grade. This paper has studied geochemical characteristcs of gas, water and sinter, and the result suggests that the CO3^2- -Na type water is the main kind of water in this ore district. Nevertheless, the SO4^2- -Na water mass （pH= 4） also exists. In the CO3^2- -Na type water, the content of Cs^＋ is （6626-7395） × 10^- 9, and the mineralization intensity is （1168.6-1284.9）× 10^-6. In the SO4^2--Na type water, the content of Cs^＋ is 1422×10^- 9 and the mineralization intensity is 471.4 × 10^- 6. The Fe-Mn-Al, Cr-Zr and Th-U geochemical graphs imply that hot water is the main genetic factor, whereas the biological effect also exerts its role. Al/Fe, Si/Al, ∑REE, ∑LREE/∑HREE, Lashalc/Ceshalc, Eu/Eu^＊ and U/Th ratios of the 2nd and 5th stages of this deposit are all different from those of the other stages. This indicates that hot water served as the main source of cesium during the 2nd and 5th stages, while the country rock only provided a little ore-forming material.

关 键 词：地球化学 热泉型铯矿床 矿床成因 搭格架 西藏 

分 类 号：P618.84[天文地球—矿床学]