Evidence for Miocene back-arc spreading in the central Scotia Sea

Abstract

Extensive marine geophysical surveys within the central Scotia Sea have revealed two areas of h e a t e d magnetic anomalies. The limited length of anomaly sequences makes unique correlation with the reversal timescale difficult, but a model is derived for the longer sequence requiring slow spreading during the period 21-6 Myr about a ridge trending 085". The north-south h e a t e d anomalies in the other sequence are well formed, but their identification is unavoidably ambiguous.