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Open Access

Testing the GAD throughout geological time

Earth, Planets and Space200759:BF03352732

Received: 20 October 2006

Accepted: 13 February 2007

Published: 20 July 2007


The suggestion that the morphology of the geomagnetic field can be tested by inspecting the statistical distribution of palaeomagnetically-determined inclination angles has been challenged on the grounds that typical plate velocities require extremely long sampling intervals—perhaps exceeding the age of the Earth—in order to adequately sample the Earth’s surface. Here, we investigate this problem by means of a random walk model and conclude that an interval equivalent to Phanerozoic time (600 Myr) is generally sufficient.

Key words

Geocentric axial dipolezonal geomagnetic fieldsrandom walk model