在Procellarum KREEP土壤中的Chang'e-5玄武岩的非KREEP来源
Heng-Ci Tian1, Hao Wang2, Yi Chen2
1Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China.
Nature
|October 19, 2021
概括
来自Procellarum KREEP Terrane (PKT) 的年轻月球基岩揭示了一个非KREEP地幔来源. 这一发现挑战了关于月球起源的先前假设
科学领域:
- 月球地质
- 星球科学
- 地质化学
背景情况:
- 对于了解月球的热和化学演变至关重要.
- 年轻的玄武岩集中在Procellarum KREEP Terrane (PKT) 中,此前被认为源自富含KREEP的地幔来源.
- 由于缺乏直接研究,这些年轻玄武岩的起源一直受到争议.
研究的目的:
- 在石化和地化学上分析来自五号任务返回的基岩石块.
- 测试PKT中的年轻玄武岩从富含KREEP的来源形成的假设.
- 为了研究月球内部的热进化.
主要方法:
- 月球基岩石块的岩石学和地化学分析.
- 大量岩石组成分析 (,铁,稀土元素,).
- 石-同位素分析.
主要成果:
- 已研究的玄武岩年龄为20亿年,
- 大量组合显示中等,高铁和KREEP类稀土元素和的度.
- -同位素表明来自非KREEP地幔来源,需要低度的部分化和部分结晶.
结论:
- 对于年轻的山马来说,KREEP不是一个必要的先决条件.
- 月球最年轻的融化可以通过持续的内部冷却历史产生,而无需在源中产生热量的元素.
- 这项研究修订了我们对月球热进化和地幔过程的理解.
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