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Updated: Mar 4, 2026

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氧化哈第纪岩石和阿基纪移动盖板构造学由杰克·希尔斯 (Jack Hills) 所揭示的石
Shane K Houchin1, François L H Tissot1, Mauricio Ibañez-Mejia2
1The Isotoparium, Division of Geological and Planetary Sciences, Caltech Pasadena, CA 91125.
概括
早期的地球地球.
科学领域:
- 地质化学 地质化学
- 早期地球的地质学
- 构造学 构造学 构造学 构造学
背景情况:
- 由于有限的早期地球材料,移动盖子构造学的起源尚不清楚.
- 碎石石提供了地球早期地历史的独特档案,延伸到40亿年前 (Ga).
研究的目的:
- 为了研究哈第安-阿凯地球的氧化还原条件和构造学设置.
- 为了分析来自澳大利亚杰克山 (Jack Hills) 的Hadean-Archean石,寻找有关早期构造学的线索.
主要方法:
- 使用了U-Pb测年法,微量元素分析和U-XANES氧气计.
- 检查了detrital石的火性核心和变态边缘.
主要成果:
- 磁性石核表明中度氧化岩 (FMQ-1至+1),挑战了高度减少的早期地球假设.
- 变态轮显示出不同的氧化还原和温度/压力 (T/P) 条件,包括高ƒO2和高T/P,低ƒO2和低T/P.
- 考古时期的石边缘 (约3.35亿年) 显示出高和低的T/P签名,表明板块受到压力.
结论:
- 地球的地幔在4.15亿年前实现了近现代的氧化还原状态.
- 移动盖子构造学在阿尔开纪早期就已经活跃起来,这表明板块构造学早些时候出现了.
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