A Small Circle of Best Fit for Spherical Data and Areas of Vulcanism

The paper sets out to investigate a statistical problem in the geophysical field of plate tectonics which amounts to obtaining a small circle of best fit in some sense. We define a small circle of best fit. Using the maximum entropy principle, an appropriate distribution is constructed, leading to the setting up of a confidence zone for this small circle. Finally, detailed analyses for a set of data in the field of plate tectonics and for a set of data concerning secular variation of the palaeomagnetic field are given.