Rare earth elements in sinters from the geothermal waters (hot springs) on the Tibetan Plateau, China
Rare earth elements in sinters from the geothermal waters (hot springs) on the Tibetan Plateau, China
复制标题
中国青藏高原地热水（温泉）烧结矿中的稀土元素
DOI：
10.1016/j.jvolgeores.2014.09.009
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发表时间：
2014-10-15
影响因子：
2.9
通讯作者：
Hu, Hai-Ping
中科院分区：
文献类型：
--
作者：
Feng, Jin-Liang;Zhao, Zhen-Hong;Hu, Hai-Ping
它们以硅质、盐质和钙质烧结矿的形式存在，但也发现了生物硅质烧结矿。分析表明，单个稀土元素与其他元素之间不存在明显的元素间关系。烧结矿的矿物学和化学组成受其成因和形成条件的影响。稀土元素的分布取决于烧结矿的来源。烧结矿中的Fe-Mn相倾向于从地热水中清除更多的稀土元素。稀土分馏和Ce异常似乎都与烧结矿中的Fe-Mn相无关。部分烧结矿的四分体呈现弱w型（凹）效应。相反，由于正Gd异常，第三四分体在某些烧结矿中表现出很大的影响。某些烧结矿中Eu正异常的成因似乎是由于水岩相互作用过程中长石的优先溶蚀作用所致。地热水中的络合配体可能对烧结矿中稀土元素的分馏有重要影响。地热水中主要的CO32-和HCO3-络合作用有利于钙质烧结矿中重稀土元素的富集。(C) 2014 Elsevier B.V.版权所有
The mineralogical and geochemical composition of sinters from the geothermal areas on the Tibetan Plateau was determined. They occur as siliceous, salty and calcareous sinters but biogenic siliceous sinters were also found. The analyses indicate that there are no distinct inter-element relationships between individual rare earth elements (REEs) and other elements. Formed from the same geothermal water, the mineralogical and chemical composition of the sinters is influenced by their genesis and formation conditions. The REE distributions depend on the origin of the sinters. Fe-Mn phases in sinters tend to scavenge more REEs from geothermal water. Neither the REE fractionation nor the Ce anomaly seems to be associated with Fe-Mn phases in the sinters. The fourth tetrads of some sinters display weak W-type (concave) effects. In contrast, the third tetrads present large effects in some sinters due to positive Gd anomalies. The origin of the positive Eu anomalies in some sinters seems to be caused by preferential dissolution of feldspars during water-rock interaction. The complexing ligands in geothermal water may contribute significantly to the fractionation of REEs in sinters. The dominant CO32- and HCO3- complexing in geothermal water favors enrichment of heavy REEs in calcareous sinters. (C) 2014 Elsevier B.V. All rights reserved.