西藏地热活动中铯的富集过程探讨  

Enrichment of Element Cesium during Modern Geothermal Action in Tibet,China

作　　者：李振清[1] 侯增谦[1] 聂凤军[1] 杨竹森[1] 曲晓明[1] 孟祥金[1] 赵元艺[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037

出　　处：《地质学报》2006年第9期1457-1464,共8页Acta Geologica Sinica

基　　金：国家重点基础研究规划"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"青藏高原热水活动的时空格架和氦同位素研究"(编号40302028)资助成果

摘　　要：硅华铯矿是青藏高原独特的铯矿床,它赋存在高温地热活动的产物——硅华中,主要分布在高原的强烈地热活动区。为什么硅华铯矿目前仅在青藏高原发现,别的地方尚未见报导,显然跟青藏高原在近期的构造运动有关。本文详细研究了Cs元素在地热流体和泉华中的特征,以及与Rb、Cl等离子的相关关系,探讨了Cs元素的地球化学行为,总结Cs元素在地热活动中的富集过程:地壳的局部重熔作用导致了Cs的预富集;岩浆的结晶、分异使Cs再次浓集;大规模的水/岩反应使流体中Cs更加富集。Geyserite Cs-deposit, occurring in the sediment of high-temperature geothermal action, is the particular Cs-deposit in Tibet. They mainly distribute in the violent geothermal active regions. The fact that the geyserite Cs-deposit is discovered only in Tibet has relation with the modern tectogenetic movement of the Tibet plateau by all appearances. This paper studied the geochemical characteristic of Cs in geothermal fluid and geyserite, the correlation with some irons （including Rb, C1, Li et al. ）. Based on the research of the geochemical activity of Cs, the paper sum up the enrichment process of Cs in geothermal activity： partial anatexis of crust conduced the preconcentrating of Cs; crystallizing, separation of magma resulted in the re-concentrating of Cs; large scale reaction of fliud-rock induced Cs more enrichment in fluid.

关 键 词：西藏 地热活动 硅华铯矿 富集过程 

分 类 号：P618.84[天文地球—矿床学]