![]() ![]() In geodesy and astronomy, the angular rotation velocity (ARV) of the Earth is understood as one full revolution of the Greenwich (zero) meridian and its average ARV value (ω), if the period (T) of rotation of the planet T=86164.09891 is measured in solar seconds ( Lambert, 1961), is (( Eq.(1)): It seems that the evolution of the Moon’s orbit since its emergence has not obeyed the periodic law and has been more complex. Furthermore, Avsyuk’s basic assumption is inconsistent with the hypotheses of the Moon origin as a mega-impact ( Zharkov, 2003) and as a result of the gravitational trapping of the Moon to the Earth’s orbit ( Malcuit et al., 1992 Zemtsov, 2007) and with astronomical observations of the constancy of the angle of inclination of the Earth’s rotation axis to ecliptics ( Shcheglov, 1974 Zharkov et al., 1996 Zharkov, 2003). Variations in palaeointensity, geomagnetic field inversion frequency and Bertrand cycles were correlated with the phases of variations in the Moon’s orbit radius after Avsyuk, but no significant correlations have been revealed ( Kurazhkovskii et al., 2008), although in the same publication the authors have concluded that mean palaeointensity is related to the Earth’s volcanic activity. If this hypothesis is valid, the retardation and acceleration of the Earth’s rotation also could have affected the behaviour of the main geomagnetic field and folding phases. Variable tidal forces would have made the Earth rotate now rapidly, now slowly. Some determinations have been made by the authors under INTAS Project 03-51-5807 at the Salmi suite and at the Ropruchei sill on the Fennoscandian Shield ( Pavlov et al., 2004 Shcherbakova, Pavlov et al., 2006).Īn interesting hypothesis of periodical variations in the Moon’s orbit radius and tidal forces during the Phanerozoic was proposed by Y.N. However, slightly more than 30 intensity determinations, consistent with modern reliability criteria, are available for this time span of about 3 Ga in geological history. Obviously, voluminous data on geomagnetic field intensity in Palaeoarchaean-Proterozoic time are needed to check this and other hypotheses. One of the Earth cooling models shows that the Earth’s internal core could be younger than it has been assumed earlier ( Labrosse et al., 2001). can be obtained by studying geomagnetic field intensity in the geological past. New evidence for the Earth’s evolution, the timing of internal core formation etc. This work provides an impetus to the palaeomagnetic study of the oldest localities. It contains about 3900 VDM values and more geomagnetic field palaeointensity values from 3 billions of years ago (Ga) to the present, but most of the data are confined to the last 100 million years (Ma). The database is available at the website: Shcherbakova has developed a global IAGA Palaeointensity Database and obtained new extensive reliable data on the magnetic virtual dipole moment (VDM) of the Earth by estimating the degree of validity of each value. ![]() ![]() In the past few years, the Research Team of the Geophysical Observatory at the Institute of Physics of the Earth, RAS, headed by V.V. ![]() However, at many international conferences earth scientists are not unanimous as to whether endogenic and cosmic processes are interrelated. The behavioral study of the Earth’s magnetic moment or palaeointensity, inversion frequency and other geomagnetic field characteristics in the remote past could have provided the basis for estimation of the time taken by global space and intraterrestrial processes. ![]()
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