概括
月球的异质岩石显示出正的欧洲异常,表明它们的形成来自于一个差异化的月球岩海洋. 这种分析有助于估计月球高原和玄武岩层的厚度.
科学领域:
- 月球地质学和地球化学
- 星球科学 星球科学
- 宇宙化学 宇宙化学
背景情况:
- 了解月球的组成和形成对于行星科学至关重要.
- 阿波罗11号的样本10085提供了关于月球高原的关键组成部分,月球的安诺托西特的见解.
- 之前的研究表明,月球分化过程影响了月球表面的组成.
研究的目的:
- 来自阿波罗11号的样本10085.5,以确定月球无线星球上的元素丰度.
- 分析稀土元素 (REE) 的分布模式,特别是欧 (Eu) 异常.
- 将这些发现用于质量平衡计算,以估计月球地和地幔厚度.
主要方法:
- 使用了仪器和放射化学中子激活分析 (NAA).
- 分析重点是主要,次要和微量元素,包括14种稀土元素 (REE).
- 用假定的月球组成和差异化模型进行质量平衡计算.
主要成果:
- 相对于普通的地石,月球上的无线石位表现出正的欧洲 (Eu) 异常.
- 质量平衡计算表明,月球高地厚度约为30公里,玄武岩底层岩石厚度约为5公里,用于全月差异化.
- 替代模型表明,在月球早期,REE和 (Ba) 的丰度与在玄武岩基石中观察到的相似.
结论:
- 月球异构体的阳性Eu异常支持它们起源于一个差异化的岩海洋.
- 该研究提供了月球高地和玄武岩层厚度的定量估计.
- 这些发现为月球早期融化,化学分化和地演变的模型做出了贡献.
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