| Numéro |
J. Phys. Colloques
Volume 49, Numéro C8, Décembre 1988
Proceedings of the International Conference on Magnetism
|
|
|---|---|---|
| Page(s) | C8-2065 - C8-2066 | |
| DOI | https://doi.org/10.1051/jphyscol:19888936 | |
Proceedings of the International Conference on Magnetism
J. Phys. Colloques 49 (1988) C8-2065-C8-2066
DOI: 10.1051/jphyscol:19888936
1 Institut für Geophysik, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
2 IBM Research Division, Zurich Research Laboratory, CH-8803 Rüschlikon, Switzerland
J. Phys. Colloques 49 (1988) C8-2065-C8-2066
DOI: 10.1051/jphyscol:19888936
MAGNETIC INTERACTION IN SELF-REVERSING ANDESITIC PUMICE IN RELATION TO IRON ALLOYS
M. Haag1, F. Heller1 et R. Allenspach21 Institut für Geophysik, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
2 IBM Research Division, Zurich Research Laboratory, CH-8803 Rüschlikon, Switzerland
Abstract
Andesitic pumice erupted in 1985 from Nevado del Ruiz volcano (Colombia) has been magnetized in opposite direction to the present geomagnetic field. This self-reversal is probably due to an exchange mechanism between two phases of the haematite-ilmenite series, which is similar to the magnetic coupling observed in synthetically grown antiferromagnetic-ferromagnetic FeMn-FeNi films produced under ultra high vacuum conditions.