Using “domino” model to study the secular variation of the geomagnetic dipolar moment

• Published in: Physics of the earth and planetary interiors Vol. 242; pp. 9 - 23
• Main Authors: Duka, B., Peqini, K., De Santis, A., Pavón-Carrasco, F.J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2015
• Subjects: Dipolar magnetic moment; Domino model; Geodynamo; Geomagnetic excursion; Geomagnetic reversal; Secular variation; Dipolar magnetic moment; Geomagnetic excursion; Secular variation; Domino model; Geodynamo; Geomagnetic reversal
• ISSN: 0031-9201; 1872-7395
• DOI: 10.1016/j.pepi.2015.03.001

•A “domino” model to study the geomagnetic field at million and millennial time-scale.•The reversal model agrees with the previous works but some differences are found.•First use of the domino model to generate time series of SV of the dipolar field.•Comparison of the domino model with different archaeomagnetic global models. Aiming to understand the physical processes underneath the reversals events of geomagnetic field, different numerical models have been conceived. We considered here the so named “domino” model, an Ising–Heisenberg model of interacting magnetic macrospins aligned along a ring. This model was proposed by Mazaud and Laj (1989) and then applied by Mori et al. (2013) to study geomagnetic field reversals. The long series of the axial magnetic moment (dipolar moment or “magnetization”) generated by the “domino” model are empirically studied by varying all model parameters. We present here some results which are slightly different from those given by Mori et al. (2013), and will provide our explanation on the presence of these differences. We also define the set of parameters that supply the longest mean time between reversals. Using this set of parameters, a large number of time series of axial magnetic moment are also generated. After de-noising the fluctuation of these time series and averaging them, we compared the resulting averaged series with the series of axial dipolar magnetic moment values supplied by CALS7k.2, and CALS10k.1b models, finding similar behavior for the all time series. In a similar way, we also compared the averaged 14,000years long series of dipolar moment with the dipolar magnetic moment obtained by the model SHA.DIF.14k.