Open AccessHemispherical Contrasts in Support for the Offset Dipole Hypothesis During the Brunhes Epoch: The Case for an Unequal Co‐axial Dipole Pair as a Possible Geomagnetic Field Source
Author(s) -
Watkins N. D.
Publication year - 1972
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1972.tb06123.x
Subject(s) - archipelago , earth's magnetic field , northern hemisphere , geology , dipole , southern hemisphere , offset (computer science) , geophysics , paleontology , climatology , geodesy , oceanography , magnetic field , physics , quantum mechanics , computer science , programming language
Summary Palaeomagnetic results from sites in the Indian Ocean (Possession and East Island in the Crozet Archipelago; New Amsterdam; and Grande Comore and Anjouan in the Comores Archipelago) and in the Atlantic Ocean (Lanzarote, Gran Canaria, Tenerife, La Palma, Hierro, in the Canary Islands) have been added to previously published results, to test Wilson's (1970) offset dipole hypothesis, for the Brunhes Epoch ( t = 0 to 0.69 My). Results from the Northern Hemisphere are consistent with the offset dipole, but the Southern Hemisphere results strongly oppose the concept. A real long‐term hemispheric disymmetry of the geomagnetic field would explain the results. The most simple model required to cause the required decrease in total field inclinations in the Northern Hemisphere only, would involve a very small axial dipole with substantial northward offset superimposed on the major centred axial dipole field.