Rare earth element distribution in some hydrothermal minerals: evidence for crystallographic control
Rare earth element distribution in some hydrothermal minerals: evidence for crystallographic control
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DOI：
10.1016/0016-7037(80)90286-0
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发表时间：
1980-07
影响因子：
5
通讯作者：
J. Morgan;G. A. Wandless
中科院分区：
文献类型：
--
作者：
J. Morgan;G. A. Wandless
用中子活化分析法测定了硬石膏（CaSO 4）、重晶石（BaSO 4）、菱铁矿（FeCO 3）和方铅矿（PbS）中稀土元素的丰度。一个简单的晶体化学模型定性地描述了稀土元素在硬石膏，重晶石，菱铁矿替代的相对亲和力。当归一化为“地壳”丰度（作为热液流体稀土元素模式的近似值），日志稀土元素丰度是一个令人惊讶的线性函数（主要阳离子的离子半径的稀土离子半径）2为三个热液矿物，单独和集体。然而，一个重要的例外是Eu，相对于相邻原子序数和三价离子半径的REE，Eu在重晶石中富集，在菱铁矿中亏损。原则上，对合适的热液矿物组合进行稀土元素分析，结合适当的实验数据，可以得到热液流体的稀土元素含量和温度。稀土元素只有很弱的亲铜倾向，这反映在方铅矿中的丰度很低-La，0.6 ppb; Sm，0.06 ppb;其余的低于检测限。
Rare earth element (REE) abundances were measured by neutron activation analysis in anhydrite (CaSO4), barite (BaSO4), siderite (FeCO3) and galena (PbS). A simple crystal-chemical model qualitatively describes the relative affinities for REE substitution in anhydrite, barite, and siderite. When normalized to ‘crustal’ abundances (as an approximation to the hydrothermal fluid REE pattern), log REE abundance is a surprisingly linear function of (ionic radius of major cation—ionic radius of REE)2for the three hydrothermal minerals, individually and collectively. An important exception, however, is Eu, which is anomalously enriched in barite and depleted in siderite relative to REE of neighboring atomic number and trivalent ionic radius. In principle, REE analyses of suitable pairs of co-existing hydrothermal minerals, combined with appropriate experimental data, could yield both the REE content and the temperature of the parental hydrothermal fluid.The REE have only very weak chalcophilic tendencies, and this is reflected by the very low abundances in galena—La, 0.6 ppb; Sm, 0.06 ppb; the remainder are below detection limits.