颠倒的分化和生成一个"原始的"下层地幔的产生
Cin-Ty A Lee1, Peter Luffi, Tobias Höink
1Department of Earth Science, MS-126, Rice University, 6100 Main Street, Houston, Texas 77005, USA. ctlee@rice.edu
Nature
|February 19, 2010
概括
地球地幔的分化是由固态对流和化提取驱动的,在地中集中不相容的元素. 一个新的假设表明,早期地球的深度融化形成了沉没的密集液体,形成了带有原始化学特征的隐藏储库.
科学领域:
- 地质化学 地质化学
- 地质物理学 地质物理学
- 行星科学 行星科学
背景情况:
- 地球的化地幔差异化主要由固态对流来决定.
- 在地幔上升过程中,部分融化会产生低密度的融化物,形成地.
- 微量元素 (例如,U,Th,K) 和贵重气体优先分裂成化物,成为不兼容的元素.
研究的目的:
- 为了调查地球内部隐藏的不可兼容元素储存库的起源.
- 质疑普遍认为这个水库仅仅是原始材料的观点.
- 为早期地球的化学差异提出一个替代模型.
主要方法:
- 对地幔对流过程的分析.
- 早期地球融化和分化的建模.
- 微量元素和贵重气体分区的解释.
主要成果:
- 融提取将不兼容的元素集中在地中,使上层地幔耗尽.
- 质量平衡表明,很大一部分不兼容的元素存在于隐藏的储存库中.
- 早期地球的整个地幔对流可能产生了深度,热融,产生了密集的液体.
结论:
- 来自早期地球深层融化的密集,结晶的液体沉入了下层地幔.
- 这个过程创造了一个隐藏的储存库,具有"原始"的化学特征,与真正的原始材料不同.
- 地球地幔的分化是一个复杂的过程,涉及到地的提取和深层地幔储存.
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