DID A LARGE DEPARTURE FROM THE GEOCENTRIC AXIAL DIPOLE HYPOTHESIS OCCUR DURING THE EOCENE? EVIDENCE FROM THE MAGNETIC POLAR WANDER PATH OF EURASIA

Abstract

Low paleolatitudes are very frequent in Eocene to Oligocene formations, particularly in the Tethyan mobile belt. These anomalies and their possible sources are discussed. They are neither due to unreliable results nor to inclination errors in sedimentary rocks. Neither can large tectonic movements explain these discrepancies. The most probable causes having been rejected, therefore, the best explanation consists in an alternative magnetic pole position for Eurasia located at 69°N, 215°E. It is proposed that the mean magnetic field of the Earth was dipolar, but that its axis has swung from one stable position to another during the middle Tertiary and was therefore sometimes different from the rotation axis.