Palaeomagnetic Evidence about the Source of the Geomagnetic Field
The availability of a large body of palaeomagnetic data from Eastern and Western Iceland has made possible several deductions about the nature of the source of the geomagnetic field. We conclude that the assumption of a centred dipole source leads to a simple and reasonable time-average dependence o...
| Published in: | Geophysical Journal International |
|---|---|
| Main Authors: | , , |
| Format: | Text |
| Language: | English |
| Published: |
Oxford University Press
1972
|
| Subjects: | |
| Online Access: | http://gji.oxfordjournals.org/cgi/content/short/28/2/213 https://doi.org/10.1111/j.1365-246X.1972.tb06124.x |
| Summary: | The availability of a large body of palaeomagnetic data from Eastern and Western Iceland has made possible several deductions about the nature of the source of the geomagnetic field. We conclude that the assumption of a centred dipole source leads to a simple and reasonable time-average dependence of absolute dipole strength on dipole orientation (dipole moment on pole position). The relationship is nearly axially symmetrical, and provides natural definitions of ‘normal‘ and ‘reversed’ fields. The normal state has been more stable over the past 12 My than the reversed state. The dependence of time-average dipole strength on dipole orientation provides a considerable constraint on any postulated mechanism for field generation, although it does not necessarily give direct insight into the behaviour in the core. |
|---|