通过核中的降水为地球发电机提供动力
Joseph G O'Rourke1, David J Stevenson1
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA.
Nature
|January 22, 2016
概括
地球的磁场,地球磁场,已经运行了数十亿年. 一项新的研究表明,来自核心的沉, 不仅仅是冷却,
科学领域:
- 地质学
- 星球科学
- 地球科学
背景情况:
- 地球的磁场源于液态外核中的对流.
- 根据古磁数据, 地磁力发电机至少运行了34亿年.
- 标准模型提出组合对流,热对流或放射性加热作为电源.
研究的目的:
- 为了研究地球地力发电机的替代能源.
- 通过铁的热导率的新发现来协调地热电机的长期运行.
- 为了解释地力发电机如何在缓慢冷却或最小的放射性加热下持续存在.
主要方法:
- 使用第一原则计算和钻石细胞实验.
- 分析铁的热导率增加对核心动态的影响.
- 模拟含矿物沉作为浮力驱动的动力来源的作用.
主要成果:
- 较高的铁热导率表明一个年轻的内核, 挑战现有的地力学模型.
- 核中的沉提供了比内核增长更有效的浮力来源.
- 这一过程允许地球历史上持续地力发电的运行.
结论:
- 降雨提供了一个可行的机制,
- 这一发现证实地力学机至少在34亿年前一直持续运行.
- 它解决了最近铁的高压实验数据出现的差异.
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