Global magnetic anomalies and the amplitude of secular variations of the geomagnetic field direction

The total amplitude of secular variations of the geomagnetic-field direction S in the Brunhes Chron (the last similar to0.8 Myr) is analyzed as a function of the distance to the centers of global magnetic anomalies. The amplitude is determined from the precision parameter of the paleomagnetic directions K [S = 81/(K)(1/2)]. Data on K are taken from paleomagnetic databases. As a result, it is possible to detect a decrease in S with increasing distance from the centers of global magnetic anomalies in the last few tens of thousands of years. During the same time interval, global magnetic anomalies have influenced paleomagnetic deviations, as reflected in the negative mean declination from the dipole field to the east of the global magnetic anomalies and the positive mean deviation to the west of the anomalies. The results obtained indicate the existence of a relationship between the sources of global magnetic anomalies and secular variations in the geomagnetic field and provide clues to the age of the core heterogeneities that were responsible for them.