EarthRef.org Reference Database (ERR) -- Consolini et al. 2000

The Earth's magnetic field has reversed its polarity hundreds of times in the Earth's history. This phenomenon is generally viewed as due to a Poisson nonstationary process. Here, the geomagnetic chron time length sequence, for the past 166 Ma, is analyzed using a multifractal approach, based on singularity analysis. The existence of a multifractal structure is the signature of the occurrence of punctuated equilibrium, which can be read as an indication of a critical configuration of the geodynamo. The results obtained are compared with those from a prototypical model of a dynamical system, introduced by Seki & Ito [1993>, and are discussed in the context of fluid motions within the Earth's outer liquid core. ¿ 2000 American Geophysical Union The Earth's magnetic field has reversed its polarity hundreds of times in the Earth's history. This phenomenon is generally viewed as due to a Poisson nonstationary process. Here, the geomagnetic chron time length sequence, for the past 166 Ma, is analyzed using a multifractal approach, based on singularity analysis. The existence of a multifractal structure is the signature of the occurrence of punctuated equilibrium, which can be read as an indication of a critical configuration of the geodynamo. The results obtained are compared with those from a prototypical model of a dynamical system, introduced by Seki & Ito [1993>, and are discussed in the context of fluid motions within the Earth's outer liquid core. ¿ 2000 American Geophysical Union