New aeromagnetic data from the western Enderby Basin and consequences for Antarctic-India break-up

Abstract

In order to enhance our understanding of the continental break-up between East India and Antarctica, a Japanese/German aerogeophysical survey was conducted off eastern Dronning Maud Land and western Enderby Land, Antarctica. The systematic survey with a line spacing of 20 km provides strong constraints on the timing of the initial break-up of India/Antarctica compared to the conjugate margin south of Sri Lanka. While the continent-ocean transition is very well marked by pronounced positive and negative magnetic anomalies, no hints on the existence of magnetic spreading anomalies north of this zone has been found in the new data set. Thus, in contrast to most recently published models, the data only support kinematic models, which include a final break-up of Sri Lanka/India from our investigated area some 90-118 Ma within the Cretaceous Normal Superchron. © 2010 by the American Geophysical Union.