Saw-toothed pattern of sedimentary paleointensity records explained by cumulative viscous remanence

Abstract

The relative paleointensity of the earth's magnetic field from ODP Site 851 has been characterized by progressive decay w x towards polarity reversals, followed by sharp recovery of pre-reversal values 1 . We resampled the Gilbert-Gaub reversal boundary of this deep-sea core, and show that during demagnetization this 'saw-toothed' pattern disappears. Further, the w x recently published Cumulative Viscous Remanence model 2 using the herewith obtained paleointensity record and w x constraints from thermal treatment replicates the saw-tooth of 1 , implying that it is of non-geomagnetic origin.