New Zealand's South Island has many extinct volcanic centres with no yet fully agreed tectonic mechanism of formation and the Dunedin volcano is one of them.

This implies that the mechanism of formation may be connected to the lithosphere unlike some other intraplate volcanoes such as the Hawaii island chain, which are rooted in the asthenosphere.

If large sections of this already thin lithosphere sank into the asthenosphere, it would be replaced with hotter rock leading to decompression melting.

[8] The Dunedin Volcano has the distinction amongst the South Island volcanics of having a potential magma melt pool still underneath it, as backed up by heat flow[9] and surface helium measurements.

[10] Accordingly there may now be a gradually re-accumulating 10 million year melt which could, with a low risk of it happening, in due course become manifest as active surface volcanism again.