Geomagnetic, Magnetotelluric, Geothermal and Seismic Signatures of Magnetic Phase Transition in the Crust
Abstract
In a GRL paper in 2005 the authors assumed that the second-order magnetic phase transition in the Earth's crust may be a possible source of geomagnetic and magnetotelluric anomalies. In that paper two consequences were mentioned: (1) some geomagnetic anomalies of unknown origin could be perhaps explained by a significant enhancement of the magnetic susceptibility at the Curie (Neel) depth, (2) this phenomenon might be also responsible for some magnetotelluric crustal conductivity anomalies. Recently we have found that the magnetotelluric effect of a hypothetical one-dimensional magnetic phase transition is a very thick and extremely high-resistivity pseudolayer, and the multidimensional responses are very mixed. In some places in the Pannonian basin the second-order magnetic phase transition can be probably really excluded, but in some other places it seems to be the only reasonable explanation for the observed geophysical anomalies. Possible geothermal and seismic signatures of this phenomenon will also be discussed. Acknowledgement: Hungarian Scientific Research Fund, T68475
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFMGP41A0766S
- Keywords:
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- 0925 Magnetic and electrical methods (5109);
- 1517 Magnetic anomalies: modeling and interpretation;
- 1540 Rock and mineral magnetism