概括
同位素比率 (-87/-86) 在上部Kiglapait入侵中增加,这是由于在融结构中的不完美保留,而不是污染. 这一发现揭示了岩源过程.
科学领域:
- 地质化学 地质化学
- 伊格尼岩石学 伊格尼岩石学
- 同位素地球化学 同位素地球化学
背景情况:
- 层层的入侵提供了关于岩演变和分化过程的见解.
- 石同位素 (石-87/石-86) 是了解岩来源和污染的关键标记物.
- 以前的研究经常将同位素变异归因于外部污染或岩混合.
研究的目的:
- 调查Kiglapait上层入口中-87/-86比率系统增加的原因.
- 评估污染,交换和岩混合与源源遗传的融特性之间的作用.
- 为了了解放射性在岩结晶过程中的行为.
主要方法:
- 在Kiglapait入侵的上10%的-87/-86比率的系统测量.
- 与主要元素 (例如,) 和微量元素 (例如,) 的同位素比例的相关性分析.
- 对潜在过程的建模,包括污染,交换和岩混合.
主要成果:
- 在上部Kiglapait入侵中观察到-87/-86比率从0.70395增加到0.70662.
- 这种同位素变异与和卢比度有很强的相关性.
- 污染,交换和岩混合被排除为观察到的趋势的主要原因.
结论:
- 石-87/石-86比率的增加归因于放射性石-87在由岩源继承的地类融结构中的不完美保留.
- 这些结构遗传效应在无水溶中更持久.
- 该研究强调了在解释岩系统中同位素变异时考虑融结构和源特性的重要性.
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