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稀土元素丰度在硬石膏(CaSo_4)、重晶石(BaSo_4)、菱铁矿(FeCo_3)和方铅矿(Pbs)中用中子活化分析测定了。一种简单的结晶化学模式定性的描述了在硬石膏、重晶石和菱铁矿中稀土元素代替的相对亲合力。当地壳的丰度正常化时(近似热液稀土元素模式),三个热水矿物个别的和集体的对数稀土元素丰度是一种惊人地线形函数。(大阳离子离子半径——稀土元素的离子半径)。然而,重要的例外是Eu,相对于稀土元素的邻近原子序数和三价离子的半径,Eu在重晶石中异常富集而在菱铁矿中缺失。原则上,共生热水矿物的成对稀土元素分析,结合适当的实验资料,能得到稀土元素含量和原始热液的温度。 稀土元素仅有微弱的亲铜倾向,反映在方铅矿上有很低的丰度——La 0.6P Pb,Sm 0.06P Pb;其余的稀土元素含量低于侦查极限。
The abundance of rare earth elements was determined by neutron activation analysis in anhydrite (CaSo_4), barite (BaSo_4), siderite (FeCo_3) and galena (Pbs). A simple crystalline chemistry model qualitatively describes the relative affinity of rare earth elements for substitution in anhydrite, barite and siderite. When the abundance of the crust is normalized (similar to the hydrothermal rare earth element model), the abundance of individual and collective log REEs of the three hydrothermal minerals is an astonishingly linear function. (Large cation ion radius - ion radius of rare earth element). However, the important exception is Eu, which is exceptionally enriched in barite and missing in siderite relative to the neighboring atomic number of the rare earth element and the radius of the trivalent ion. In principle, pairs of rare earth elements in the symbiotic hydrothermal minerals, combined with appropriate experimental data, can yield the REE content and the temperature of the original hydrothermal solution. Rare earth elements have only a weak pro-copper affinity, reflecting a very low abundance of La 0.6 Pb Pb and Sm 0.06 Pb Pb on galena; the rest of the REEs are below the detection limit.