Initial phase of the West Scotia mid-oceanic ridge opening

Abstract

The first map illustrating the position of anomaly C12 extending in the NE-SW direction (25°) in the eastern peripheral part of the West Scotia Ridge is presented. Calculations of the paleomagnetic anomalies show that the spreading initiated in the period corresponding to Chron C12r (31.116–33.266 Ma ago). Chron C11r (30.217–30.627 Ma ago) was marked by a 200 km northwestward jump of the spreading axis. The calculation of the Euler poles and the rotation angles made it possible to reconstruct the zone of the initial breakup between South America and the Antarctic Peninsula along the western periphery of the continental Terror Rise.