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来自系列地化学的地幔羽毛动态的洞察力
Bernard Bourdon1, Neil M Ribe, Andreas Stracke
1Laboratoire de Géochimie et Cosmochimie, Institut de Physique du Globe de Paris-CNRS, 4 Place Jussieu, 75252 Paris cedex 05, France. bourdon@erdw.ethz.ch
Nature
|December 8, 2006
概括
地幔羽毛,在地球石化层下面有争议的上升,由热点岩中的系列数据证实. 这项研究将浮力流与地幔温度联系起来,提供了地幔羽毛的证据.
科学领域:
- 地质物理学 地质物理学
- 地质化学 地质化学
- 火山学 火山学是一门学科.
背景情况:
- 作为热点火山来源的地幔羽毛的存在是地球科学中长期存在的争论.
- 了解地幔羽毛对于理解地球地幔的热,动态和组成演变至关重要.
研究的目的:
- 通过热点岩中的地化学标记物来调查地幔羽毛的存在和特征.
- 建立热点的浮力流和它们相关的地幔温度之间的直接关系.
主要方法:
- 分析来自不同热点的火山岩中的系列不平衡.
- 地化学数据与浮力流量的地物理测量结果的相关性.
主要成果:
- 系列不平衡数据提供了热点下方热和浮动的上游 (地幔羽毛) 的直接证据.
- 较弱的热点 (例如,冰岛,阿佐尔群岛) 与较强的热点 (例如,夏威夷) 相比,表现出较低的地幔过剩温度.
- 在热点的浮力流和其过度的地幔温度之间发现了直接的相关性.
结论:
- 该研究证实了地幔羽毛的存在,作为热点火山活动背后的驱动力.
- 这些发现阐明了羽毛浮力和热异常之间的关系,促进了我们对地幔动态的理解.
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