铁在地球内核边界的融化基于快速的X射线衍射
S Anzellini1, A Dewaele, M Mezouar
1Commissariat à l'Énergie Atomique, Direction des Applications Militaires, Île de France, Arpajon Cedex, France. simone.anzellini@cea.fr
概括
研究人员确定了铁在地球内核边界的点. 这一发现表明,核心-地幔边界的热量流量很高,可能导致地幔部分融化.
科学领域:
- 地质物理学 地质物理学
- 高压物理学的高压物理
- 材料科学是一种材料科学.
背景情况:
- 地球的核心包括固体内核和液体外核,主要是铁.
- 内核边界 (ICB) 的温度接近铁的点330千兆帕斯卡尔 (GPa).
- 铁在极端压力下化的行为缺乏科学共识.
研究的目的:
- 在ICB压力下实验性地确定铁的化温度.
- 改进地球热演变和核心动态的模型.
主要方法:
- 进行了静态激光加热的钻石天细胞实验.
- 基于同步射线的快速X射线衍射被用作主要的融诊断.
- 实验达到高达200 GPa 的压力.
主要成果:
- 铁在ICB的化温度估计为6230±500凯尔文.
- 实验数据被推断为330 GPa的压力范围.
- 结果表明,在核心-地幔边界的热量流量很高.
结论:
- 估计的高化温度支持外核中的强烈对流.
- 高热量流可能导致下层地幔内部分融化.
- 这些发现有助于理解行星核心热力学和地力学.
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