Geomagnetic polarity transitions of the Gilbert and Gauss chrons recorded in marine marls from Sicily

Abstract

One of the most fascinating phenomena of geophysics is the fact that in the geological past the Earth's magnetic field has frequently reversed its polarity. These polarity transitions are accurately established during at least the past 165 Myr - from their recording in the ocean floor: the marine magnetic anomalies. The (changes in) reversal frequency during the geological past may tell us something about long-term changes in the lower mantle and outer-core processes, and hence constrain the origin of the field itself. The subject of this thesis, however, deals with an entirely different scale of time: that of individual polarity reversals, taking place in several thousands of years.