Magnitude of the anomalous geomagnetic fields

Authors

  • I.I. Rokityansky S.I. Subbotin Institute of Geophysics, National Academy of Sciences of Ukraine, Kiev, Ukraine, Ukraine
  • A.V. Tereshyn S.I. Subbotin Institute of Geophysics, National Academy of Sciences of Ukraine, Kiev, Ukraine, Ukraine

DOI:

https://doi.org/10.24028/gj.v47i2.322473

Keywords:

electrical conductivity anomaly, normalized anomalous field, inductive anomaly, conductive anomaly, superchanneling

Abstract

The normalized amplitudes of the anomalous geomagnetic field variations (presented by tipper C) with period T>200 s arising around electrical conductivity anomalies have been considered. C>1 means that the secondary (induced) field is greater than the primary (inducing) one. Worldwide, the mean observed tippers are C=0.3 for coastal observatories and C=0.15 for inland ones. The maximum tippers are 1.5 for coastal and C=1.6 for inland observatories. Modeling realistic anomalies with uniform conductivity yields C up to 2.5. The larger C can arise in a non-uniform conductor due to the superchanneling effect.

References

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Published

2025-04-07

How to Cite

Rokityansky, I., & Tereshyn, A. (2025). Magnitude of the anomalous geomagnetic fields. Geofizicheskiy Zhurnal, 47(2). https://doi.org/10.24028/gj.v47i2.322473

Issue

Vol. 47 No. 2 (2025)

Section

Conferences

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Copyright (c) 2025 I.I. Rokityansky, A.V. Tereshyn

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