Comportamento da Anomalia Magnética do Atlântico Sul para os últimos 105 anos

In this paper, we discuss the characteristics of the South Atlantic Magnetic Anomaly (SAMA) for the last century. Some authors relate the origin of the SAMA to the offset of the eccentric dipole of the Earth’s magnetic field. There are several ways for defining the SAMA geographical location. We used in this work the minimum intensity values of the field. The change in the westward drift of the Anomaly may correspond to changes in the motion of the fluid in the outer core. The intensity curve shows three intervals with different behavior for the studied period. It may be speculated that these changes can be related to geomagnetic jerks. However, the SAMA and other similar anomalies should be studied in the thousands and the million years time scales in order to improve an interpretation in terms of the Geodynamo Theory.