10 Nov 2011

Auckland's New Volcanoes

From Our Changing World, 9:06 pm on 10 November 2011

Boggust Park Volcano

Boggust Park Volcano is one of the previously unrecognised volcanoes recently discovered in Auckland - in Bruce Hayward's words 'the new volcanoes are subtle features on the landscape' (image: A. Ballance)

Bruce Hayward and his colleagues from Geomarine Research hit the news earlier this year with the rediscovery of the Grafton volcano, recognized by Hochstetter in his 1864 map of Auckland volcanoes, but then forgotten. The find brought the tally of volcanoes in the Auckland area to 50. Now four new finds and another forgotten volcano bring the tally to either 53 or 55, depending on whether three of the craters are considered to be volcanoes in their own right or are a related cluster.

The previously unrecognised craters were identified on the new online Auckland City digital map, which has detailed contours at 50 centimetre intervals.

Volcanoes of Auckland book coverBruce Hayward takes Alison Ballance on a tour of the new finds in South Auckland, beginning with Boggust Park in Favona, Mangere, a crater which appears to be at least 130,000 years old. Next they visit the three Puhinui Craters in Puhinui Reserve in Wiri, about 800 metres from the southern-most volcano in the Auckland volcanic field – Matukutureia or McLaughlin Mountain.

The ‘forgotten crater’, Cemetery Crater, was identified by the late Ernie Searle in the 1960s, but not recognised by most geologists since then.

To find out more about the Auckland volcanic field head to Bruce Hayward’s newly released book ‘Volcanoes of Auckland – an essential guide (Auckland University Press 2011) – which includes all the volcanoes, except of course the newly identified ones!