A comparison of upper mantle subcontinental electrical conductivity for North America, Europe, and Asia

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W.H. Campbell
E.R. Schiffmacher


Spherical harmonic analysis coefficients of the external and internal parts of the quiet-day geomagnetic field variations (Sq), separated for the North American, European, Central Asian and East Asian regions, were used to determine conductivity profiles to depths of about 600 km by the Schmucker equivalent-substitute conductor method. All three regions showed a roughly exponential increase of conductivity with depth. Distinct discontinuities seemed to be evident near 255-300 km and near 450-600 km. Regional differences in the conductivity profiles were shown by the functional fittings to the data. For depths less than about 275 km, the North American conductivities seemed to be significantly higher than the other regions. For depths greater than about 300 km, the East Asian conductivities were largest.

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Campbell, W., & Schiffmacher, E. (1986). A comparison of upper mantle subcontinental electrical conductivity for North America, Europe, and Asia. Journal of Geophysics, 59(1), 56-61. Retrieved from https://journal.geophysicsjournal.com/JofG/article/view/232


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