Resolving atmospheric contaminants in mantle noble gas analyses
Resolving atmospheric contaminants in mantle noble gas analyses
复制标题
在地幔稀有气体分析中解决大气污染物
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
G. Turner
中科院分区：
文献类型：
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作者：
D. Harrison;P. Burnard;M. Trieloff;G. Turner
作为限制地幔稀有气体预算的一部分，我们评估了最近发表的高质量稀有气体数据，并报告了新的数据，以使三维（3 - D）建模技术的使用合理化。这些数据的建模表明，传统的二维混合图不足以完全约束混合系统和地幔末端成分。我们表明，这些地幔稀有气体分析在不同程度上受到了大气污染物分馏的影响，而与喷发环境无关。这种成分也可以出现在类地幔氖或氩同位素比率的分析中。以前对大部分样品的地幔端元40Ar/36Ar和129Xe/130Xe组成的估计可能是最小值。事实上，很可能在目前的文献中没有完全纯净的地幔挥发物的分析。
As part of an ongoing initiative to constrain mantle noble gas budgets, we evaluate both recently published high‐quality noble gas data and report new data in order to rationalize the use of three‐dimensional (3‐D) modeling techniques. Modeling of these data shows that traditional 2‐D mixing plots are not adequate tools to fully constrain mixing systems and mantle end‐member compositions. We show that these mantle noble gas analyses are compromised to varying degrees by the addition of a fractionated atmospheric contaminant, irrespective of eruption setting. This component can also be present in analyses with mantle‐like neon or argon isotope ratios. Previous estimates for the mantle end‐member 40Ar/36Ar and 129Xe/130Xe compositions of most of these samples are likely to be minimum values. In fact it may well be that there are no analyses in the present literature that have completely unadulterated mantle volatiles present.