High mass resolution ion microprobe analysis of rare earth elements in silicate glass, apatite and zircon: lack of matrix dependency
High mass resolution ion microprobe analysis of rare earth elements in silicate glass, apatite and zircon: lack of matrix dependency
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DOI：
10.1016/s0009-2541(01)00366-7
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发表时间：
2002-04-01
期刊：
影响因子：
3.9
通讯作者：
Fukuoka, T
中科院分区：
文献类型：
--
作者：
Sano, Y;Terada, K;Fukuoka, T
采用在1%峰高处具有9300高质量分辨率的离子微探针方法测量了硅酸盐玻璃、磷灰石和锆石中所有稀土元素（REE：镧、铈、镨、钕、钐、铕、钆、铽、镝、钬、铒、铥、镱和镥）的浓度。从英安岩中提取的磷灰石中稀土元素的观测含量与同位素稀释 - 热电离质谱（ID - TIMS）方法测量的结果在2倍标准偏差下30%的误差范围内吻合良好。几颗锆石中重稀土元素的含量与ID - TIMS和仪器中子活化分析（INAA）测量的结果一致，而离子微探针测量的轻稀土元素丰度明显低于其他方法。这种差异部分是由于锆石晶体内存在1 - 5微米的磷灰石包裹体。在硅酸盐玻璃中观测到的稀土元素二次离子产率与在磷灰石和锆石中的呈现出非常相似的趋势。由于硅酸盐玻璃的化学成分与磷灰石和锆石明显不同，稀土元素的相对二次离子产率可能不受基体效应影响，这是本研究最重要的发现。计算得到的稀土元素在熔体和磷灰石之间的分配系数与报道值吻合良好，而熔体和锆石之间的系数与文献中的不一致。锆石中稀土元素系数随离子半径的对数增加而增加，表明系数呈幂律依赖关系。（C）2002爱思唯尔科学出版社。保留所有权利。
The concentrations of all rare earth elements (REE: La, Ce, Pr, Nd, Sin, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb and Lu) in silicate glass, apatite and zircon were measured by an ion microprobe method with a high mass resolving power of 9300 at 1% peak height. Observed contents of REE in apatite extracted from a dacite agree well with those measured by the isotope dilution-thermal ionization mass spectrometry (ID-TIMS) method within 30% error at 2sigma. The contents of heavy REE in several zircons are consistent with those measured by ID-TIMS and instrumental neutron activation analysis (INAA), while the light REE abundances are significantly lower by ion microprobe than by the other methods. The discrepancy is partly due to the presence of 1-5-mum inclusions of apatites within zircon crystals. Secondary ion yields of REE observed in a silicate glass show a very similar trend to those in apatite and zircon. Since the chemical composition of the silicate glass is appreciably different from the apatite and zircon, relative secondary ion yields of REE are probably independent from matrix effect, which is the most important finding of this work. Calculated partition coefficients of REE between melt and apatite agree well with reported values while the coefficients between melt and zircon are discrepant from those in literature. The REE coefficients in zircon increase with increase of the ionic radius logarithmically, suggesting power law dependence of the coefficients. (C) 2002 Elsevier Science B.V. All rights reserved.