相关实验视频
Updated: Jul 7, 2026

04:21
Small Volume (1-3L) Filtration of Coastal Seawater Samples
Published on: June 19, 2009
在北美西部下方的地幔流域
1Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA. silver@dtm.ciw.edu
概括
北美西部下的地幔流向向东移动,反对板块运动. 这种微弱的合表明,深层地幔密度的变化,可能来自古老的法拉隆板,驱动了流动.
科学领域:
- 地质物理学 地质物理学
- 构造物理学 构造物理学
- 地震学 地震学
背景情况:
- 构造板的表面运动是众所周知的.
- 然而,相应的水平地幔流量在很大程度上仍未确定.
- 了解地幔流动对于板块构造学至关重要.
研究的目的:
- 为了估计北美西部下方的水平地幔流场.
- 为了研究地幔流和构造板运动之间的合.
主要方法:
- 结合了表面变形观测和上层地幔地震异性质数据.
- 使用热点参考框架进行速度计算.
主要成果:
- 估计的地幔速度为5.5 +/- 1.5厘米/年,由于东.
- 观察到的地幔流动几乎与北美板块运动 (西南西) 相反.
- 地幔流表现出与表面板的弱合,导致最小的阻力力.
结论:
- 估计的地幔流场可能受到地幔密度异质性的影响.
- 这些异质可能源于古代法拉隆海洋板的残余.
- 这一发现提供了对影响地表构造的深层地球过程的见解.
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