在高压和高温实验中,研究了日渐增长的地球表面的核心-地幔分离
概括
地球的核心和地幔可能没有通过简单的金属酸盐相互作用达到平衡. 实验数据表明,核心-地幔分离涉及复杂的过程,而不仅仅是基本的化学平衡.
科学领域:
- 地质化学 地质化学
- 行星科学 行星科学
- 地球科学 地球科学 地球科学
背景情况:
- 在地球的酸盐地幔中观察到的 siderophile 元素的丰度与在低压和低温度下与核心的平衡分离不一致.
- 一个提出的解决方案表明,在核心形成过程中高压和高温度的平衡可以解释这些丰度.
研究的目的:
- 在高压和高温下实验性地确定液体金属和液体酸盐相之间的 siderophile 元素的分布.
- 评估简单金属酸盐平衡解释地球地幔中观察到的 siderophile 元素丰度的可能性.
主要方法:
- 实验确定 siderophile 元素的分离.
- 在100千巴和2000摄氏度模拟核心-地幔边界条件.
主要成果:
- 实验结果表明,在高压和高温下,简单的金属平衡不太可能解释观察到的 siderophile 元素丰度.
- 在模拟的核心形成条件下的分区行为不支持简单的平衡模型.
结论:
- 地球核心和地幔的分离是一个复杂的过程.
- 简单的平衡模型不足以解释核心和地幔之间 siderophile 元素的分布.
- 其他或更复杂的机制控制着地球核心和地幔的形成.
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