Affordable Access

Publisher Website

Overriding of the Indian-Antarctic ridge: Origin of emerald basin and migration of late cenozoic volcanism in Southern New zealand and Campbell Plateau

Publication Date
DOI: 10.1016/0040-1951(84)90125-2
  • Geography


Abstract Examination of plate reconstructions of the Neogene interactions among the Indian, Antarctic and Pacific plates suggests that the New Zealand and Campbell Plateau portion of the Pacific plate has overridden the site of mantle upwelling formerly associated with the southeastern end of the Indian-Antarctic ridge. The site of mantle upwelling can be projected to have migrated in a fan-shaped pattern from a NNE-SSW trend across South Island, New Zealand and along the western edge of the Campbell Plateau in Oligocene time to its present position along the southeast continental slope of the Campbell Plateau. This migration has been closely followed by the eruption of alkaline basaltic volcanic rocks which display a similar fan-shaped age distribution and which we interpret as evidence of the persistence of the mantle upwelling process for tens of millions of years after its overriding by continental lithosphere. The Emerald Basin and Macquarie Ridge complex, which formed in post-Eocene time at the western margin of the Campbell Plateau, resulted by “secondary spreading” when overriding of the Indian-Antarctic ridge by the Campbell Plateau juxtaposed the Indian and Pacific plates.

There are no comments yet on this publication. Be the first to share your thoughts.