Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46539 10.2205/2020ES000740 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Inverse problem for the Earth's core evolution model Inverse problem for the Earth's core evolution model Reshetnyak M Yu Reshetnyak M Yu m.reshetnyak@gmail.com Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences and Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Sciences ru Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences and Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Sciences ru 20 5 29 10 2021 https://rjes.ru/en/nauka/article/46539/view

The size and the age of the inner core impose constraints in modeling of the Earth's core evolution. The origin of the solid core corresponds to the change in convection regime in the core and, correspondingly, to the change in the magnetic field behavior. Meanwhile the standard evolutionary models predict quite young inner core that is not supported by the palaeomagnetic observations, which claim existence of geomagnetic field older than 3 Gy. We solve the inverse problem and find parameters of the model with the inner core older than 3 Gy.

The size and the age of the inner core impose constraints in modeling of the Earth's core evolution. The origin of the solid core corresponds to the change in convection regime in the core and, correspondingly, to the change in the magnetic field behavior. Meanwhile the standard evolutionary models predict quite young inner core that is not supported by the palaeomagnetic observations, which claim existence of geomagnetic field older than 3 Gy. We solve the inverse problem and find parameters of the model with the inner core older than 3 Gy.

 Liquid core thermal and compositional convection geodynamo Liquid core thermal and compositional convection geodynamo

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