Palaeomagnetic-pole errors and a 'small-circle' assessment of the Gondwanan polar-wander path

Abstract

The Gordon, Cox & O'Hare (1984) method has been used for denying small-circle' arcs for a series of independently determined apparent polar-wander paths.The 'small-circle approach is considered physically sensible, but unfortunately still requires excessive subjective 'assistance' to select the most plausible Euler poles and Euler colatitudes particularly when there is little relative motion between the continent and the pole. None the less, polar-wander paths can be divided into prolonged 'tracks' separated by brief 'cusps'. The cusps can be associated with particular tectonic events within the continent or groups of continents. This technique thus has the potential for providing a more geophysically realistic definition of apparent polar-wander paths that can be used to help identify non-Gaussian errors in palaeomagnetic data. In addition the sharpness of most cusps provides a precise age for the onset or cessation of particular tectonic events. The simultaneous occurrence of such cusps in more than one continent also enables an assessment of the global importance of such events.