Институт земного магнетизма, ионосферы и распространения радиоволн им. Н. В. Пушкова Российской академии наук
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
It is shown that during reversals in geodynamo models the minimum amplitudes of the dipole, quadrupole and octupole coincide. Since the characteristic time of the reversal is close to the oscillations of the large-scale geomagnetic field, a similar analysis was carried out for the minima of the amplitude of the dipole magnetic field over the past 100 thousand years. It turned out that in this case such synchronization also occurs. It can be assumed that reversals and large scale variations of the geomagnetic field between the reversals have a lot in common. The wavelet analysis carried out indicates that the concept of the main geodynamo cycle is very arbitrary: the period of oscillation can vary from 8–10 thousand years to 20–30 thousand for a dipole. Analysis of the evolution of the Mauersberger spectrum allows us to conclude that magnetic field fluctuations observed at the Earth’s surface are associated with the transfer of the magnetic field to the surface of the liquid core and can hardly be described by functions periodic in time.
geodynamo, core-mantle boundary, magnetic field modes synchronization
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