Paleomagnetic records of geomagnetic field reversals and the morphology of the transitional fields

The reversal of polarity of the earth's magnetic field is one of the most remarkable features of our planet's magnetism. A proper documentation of reversal phenomena may therefore be expected to yield useful ideas about the generation of the field. Reversals are also of interest to geologist; they have given rise to a new stratigraphy, allowed us to map the history of the ocean basins and to trace the movement of plates. The subject of reversals was comprehensively reviewed by Bullard (1968) and again more recently by Jacobs (1976). In this paper, we review paleomagnetic records of reversals and attempts to determine the geometry of transitional fields.