In the Cambrian, the paleo-Pacific margin of the Gondwana supercontinent included East Antarctica,
Australia, Tasmania and New Zealand and was affected by themajor Ross-Delamerian Orogeny. In Antarctica,
evidence suggests that this resulted from oblique subduction and that in northern Victoria Land it was accompanied by
the opening and subsequent closure of a back-arc basin. Comparison of the type and timing of sedimentary, magmatic
and metamorphic events in areas noted above shows strong similarities between northern Victoria Land and New
Zealand. In both regions Middle Cambrian volcanites are interpreted as arc/back-arc assemblages produced by west-directed subduction; sediments interbedded with the volcanites show provenance both from the arc and from the
Gondwana margin and therefore place the basin close to the continent. Back-arc closure in the Late Cambrian was
likely accomplished through a second subduction system