概括
在下层地的石中发现的原生铁 (Fe(0) 表明地球深层地的环境减少了. 这一发现影响了对来自石质层的磁异常的解释.
科学领域:
- 地质化学 地质化学
- 矿物学是什么?矿物学是什么?
- 地质物理学 地质物理学
背景情况:
- 下层地的颗粒石石提供了对地球深层过程的洞察力.
- 在这样的地质环境中,很少发现原生铁 (Fe(0)).
研究的目的:
- 调查土生土长的铁在下层地的石中的存在和影响.
- 为了确定大陆下层和上层地幔的氧化状态.
主要方法:
- 来自西非金伯利特管道的石分析.
- 磁性测量以量化铁金属丰富度.
- 地热测量和氧气地气测量以确定平衡条件.
主要成果:
- 原生铁 (Fe ((0)) 被识别为石榴石和伊尔梅尼特的分解产物.
- 铁金属在体积上占比不到0.1%.
- 在铁石和磁铁石缓冲层之间发生了平衡.
结论:
- 观察到的铁石和磁石缓冲层可能代表大陆下层地的氧化状态和耗尽的石质层上层地.
- 铁磁原生铁是稳定的到大约95公里的深度.
- 这一发现对于解释长波长静磁异常至关重要.
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