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

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

来自大洋钻探计划（ODP）851站的地球磁场相对古强度的特征是，在磁极反转前逐渐衰减，之后又急剧恢复到反转前的值[1]。我们对该深海岩芯的吉尔伯特 - 高斯反转边界重新进行了采样，结果表明在退磁过程中这种“锯齿状”模式消失了。此外，最近发表的累积黏滞剩磁模型[2]使用此处获得的古强度记录以及热处理的约束条件，重现了[1]中的锯齿状模式，这意味着它并非源于地磁。