地幔斜率和山脊细分的情况
Satish C Singh1, Ken C Macdonald
1Laboratoire de Géosciences Marines, Institut de Physique du Globe de Paris, 4 place Jussieu, Paris 75252, France. singh@ipgp.jussieu.fr
Nature
|April 28, 2009
概括
地幔上升通常是对称的,但新的地震数据表明它可能是倾斜的. 然而,这种扭曲地幔上升的证据及其影响并未得到现有数据的充分支持.
科学领域:
- 地质物理学 地质物理学
- 地震学 地震学
- 构造学 构造学 构造学 构造学
背景情况:
- 在中洋山脊上,地幔上升通常被认为是对称的.
- 之前的研究表明,基于对低速度区域的地震观测,地幔上升倾斜.
研究的目的:
- 重新评估关于地幔上升的地震数据的解释.
- 评估关于地幔流和脊细分的结论的可靠性.
主要方法:
- 对地震波速度数据的分析.
- 对地幔低速区 (MLVZ) 的解释进行批评.
主要成果:
- 由Toomey等人提出的地幔低速度区 (MLVZ). 不能充分受到其地震数据的约束.
- 观察到的地震异常并不能最终支持不对称的地幔上升.
结论:
- 关于斜地幔上游的推断没有得到现有数据的支持.
- 基于不对称的上游的结论,关于山脊细分和星球流的结论是不可靠的.
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