On the nature of the earth’s magnetic field

• Дата: 2024
• Автор: Gordienko, Vadim
• Формат: Стаття
• Мова: English
• Опубліковано: Subbotin Institute of Geophysics of the NAS of Ukraine 2024
• Теми: Earth’s magnetic field; convection in the core; global asthenosphere
• Онлайн доступ: https://journals.uran.ua/geofizicheskiy/article/view/302519
• Назва журналу: Geofizicheskiy Zhurnal

The block of information analyzed in the article includes the currently accepted ideas about the main source of the magnetic field as the axial dipole, the action of which is supplemented by a long series of regional sources. The dipole exists long enough to ignore the influence of the process of its formation, moves in the body of the planet and changes orientation to the opposite one. The duration of the polarity conservation periods varies arbitrarily by two orders of magnitude. There is no physical justification for this strange mechanism; the assumed vehicle is thermal convection in the liquid core of the Earth. It is unknown what energy sustains the heat and mass transfer and how it leads to the listed exotic properties of the magnetic field source. As an alternative, it is proposed to consider convective flows in the global asthenosphere, caused by the influence of active processes in the tectonosphere. Its volume is comparable to the volume of the outer (liquid) core. The global asthenosphere is a layer of partial melting beneath the entire Earth’s surface at depths of about 800―1100 km. It was discovered by analyzing the thermal history of the planet. Energy sources can be radioactive decay and polymorphic transformations of matter. Several convective cells can be located within the global asthenosphere; the superposition of their effects presumably forms the main part of the Earth’s magnetic field. The preliminary joint solutions of the electromagnetic and hydrodynamic problems available in the literature (for the outer core) indicate, in the author’s opinion, that the problem deserves a more substantive study.