Москва, г. Москва и Московская область, Россия
УДК 55 Геология. Геологические и геофизические науки
УДК 550.34 Сейсмология
УДК 550.383 Главное магнитное поле Земли
ГРНТИ 37.01 Общие вопросы геофизики
ГРНТИ 37.15 Геомагнетизм и высокие слои атмосферы
ГРНТИ 37.25 Океанология
ГРНТИ 37.31 Физика Земли
ГРНТИ 38.01 Общие вопросы геологии
ГРНТИ 36.00 ГЕОДЕЗИЯ. КАРТОГРАФИЯ
ГРНТИ 37.00 ГЕОФИЗИКА
ГРНТИ 38.00 ГЕОЛОГИЯ
ГРНТИ 39.00 ГЕОГРАФИЯ
ГРНТИ 52.00 ГОРНОЕ ДЕЛО
ОКСО 05.00.00 Науки о Земле
ББК 26 Науки о Земле
ТБК 63 Науки о Земле. Экология
BISAC SCI SCIENCE
According to the model of the Earth’s cooling, before the solid core origin, there was a sub-adiabatic layer at the core-mantle boundary several hundred kilometers thick. In this layer magnetic field generation was suppressed. Removing the field generation region from the Earth’s surface led to an effective weakening of the small-scale component of the magnetic field. After the solid core appeared, convection extended throughout the whole bulk of the core with the possible exception of the F-layer at the core-mantle boundary, which is no more than 100 km thick. As a result the non-dipole counterpart of the magnetic field should be stronger at the Earth’s surface. The decrease of the ratio of the dipole to non-dipole field with the origin of the solid core was an order of magnitude or more.
geodynamo, core-mantle boundary, Earth’s cooling, inner core
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