NPG Nonlinear Processes in Geophysics NPG Nonlin. Processes Geophys. 1607-7946 Copernicus Publications Göttingen, Germany 10.5194/npg-13-525-2006 On effect of precession-induced flows in the liquid core for early Earth's history Shalimov S. L. 1 2 Institute of Physics of the Earth, Moscow, Russia Space Research Institute, Moscow, Russia 04 10 2006 13 5 525 529 Copyright: © 2006 S. L. Shalimov 2006 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://npg.copernicus.org/articles/13/525/2006/npg-13-525-2006.html The full text article is available as a PDF file from https://npg.copernicus.org/articles/13/525/2006/npg-13-525-2006.pdf

Secondary and tertiary flow patterns seen in experiments simulating flow in the Earth's liquid core induced by luni-solar precession of the solid mantle (Vanyo et al., 1995) hint at the development of non-axisymmetric columnar periodic structures. A simple interpretation of the structure formation is presented in a hydrodynamic approach. It is suggested that if similar flow patterns can occur in the Earth's liquid core enclosed into precessing and rotating mantle then kinematic of the flows may be regarded as a possible geodynamo mechanism for early Earth's history (before the solid core formation).

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