中洋山脊玄武岩中的还氧异质性是地幔源的函数
Elizabeth Cottrell1, Katherine A Kelley
1National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, USA. cottrelle@si.edu
概括
地球 地球 地球 地球 地球 地球
科学领域:
- 地质化学 地质化学
- 石化学 石化学是一门学科.
- 地球科学 地球科学 地球科学
背景情况:
- 地球上层地幔的氧化状态影响和记录地幔演变.
- 上层地幔氧化状态的系统细度变化以前没有在中洋脊基岩中被发现.
研究的目的:
- 为了研究上层地幔氧化状态的系统变化.
- 了解地幔氧化状态和地幔源组成之间的关系.
主要方法:
- 全球对中洋脊玄武岩玻璃的调查.
- 分析Fe(3+) /ΣFe的比率.
- 与地幔丰富指数 (例如87Sr/86Sr,208Pb/204Pb,Ba/La,Nb/Zr) 的相关性分析.
主要成果:
- 地幔氧化状态随地幔源组成而有系统的变化.
- 丰富的地幔比枯竭的地幔更小,由Fe3+/ΣFe和丰富指数之间的负相关性表明.
- 碳被认为是制造减少和丰富的岩石的一个因素.
结论:
- 地幔氧化状态与地幔源组成有关.
- 碳在减少和丰富中洋山脊岩中起着重要作用.
- 这项研究揭示了上层地幔氧化状态的微小变化.
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