Can we probe the conductivity of the lithosphere and upper mantle using satellite tidal magnetic signals?
Can we probe the conductivity of the lithosphere and upper mantle using satellite tidal magnetic signals?
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DOI：
10.1002/2015gl063540
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发表时间：
2015-05-16
影响因子：
5.2
通讯作者：
Sabaka, T.
中科院分区：
文献类型：
--
作者：
Schnepf, N. R.;Kuvshinov, A.;Sabaka, T.
一些研究令人信服地证明，月球半日（M2）海流引起的磁场可以在卫星观测中识别出来。这一结果鼓励使用M2卫星磁数据来约束海洋区域的地下电导率。传统的基于卫星的磁层感应研究由于主要源和感应源之间的感应耦合而对导电结构非常敏感。相比之下，来自海洋潮汐信号的电偶可以研究导电性较低、较浅的结构。我们进行了全球三维电磁数值模拟，以研究M2信号对不同深度电导率分布的敏感性。我们的灵敏度分析结果表明，利用卫星高度探测到的M2海洋信号探测岩石圈和上地幔电导率是有希望的。我们的模拟还表明，M2海底电场和磁场数据可能提供互补的细节，以更好地约束岩石圈电导率。
A few studies convincingly demonstrated that the magnetic fields induced by the lunar semidiurnal (M2) ocean flow can be identified in satellite observations. This result encourages using M2 satellite magnetic data to constrain subsurface electrical conductivity in oceanic regions. Traditional satellite-based induction studies using signals of magnetospheric origin are mostly sensitive to conducting structures because of the inductive coupling between primary and induced sources. In contrast, galvanic coupling from the oceanic tidal signal allows for studying less conductive, shallower structures. We perform global 3-D electromagnetic numerical simulations to investigate the sensitivity of M2 signals to conductivity distributions at different depths. The results of our sensitivity analysis suggest it will be promising to use M2 oceanic signals detected at satellite altitude for probing lithospheric and upper mantle conductivity. Our simulations also suggest that M2 seafloor electric and magnetic field data may provide complementary details to better constrain lithospheric conductivity.