Saw-toothed pattern of relative paleointensity records and cumulative viscous remanence

Abstract

Several studies of relative paleointensity data derived from marine sediments spanning the last 4 Myr display an asymmetrical "saw-toothed" pattern. Polarity reversals of the geomagnetic field are associated with low points in paleofield intensity, preceded by a long-term progressive decay of the field and followed by a rapid post-transitional recovery [1-3]. Since similar behavior is observed in far-flung sites whose rock magnetic records are different, it is argued that the world-wide "saw-toothing" represents geomagnetic field behavior [3]. We present an alternative explanation, calling on the effect of "hard" viscous remanence.