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Auckland Volcanic Field


The Auckland volcanic field is an area of monogenetic volcanoes covered by much of the metropolitan area of Auckland, New Zealand's largest city, located in the North Island. The field's 53 volcanoes (or thereabouts) have produced a diverse array of maars (explosion craters), tuff rings, scoria cones, and lava flows. Each volcano has erupted for just one period, lasting for weeks to several years, except for Rangitoto Island, which erupted repeatedly. The field is fuelled entirely by basaltic magma, unlike the explosive subduction-driven volcanism in the central North Island, such as at Mount Ruapehu and Lake Taupo. The field is currently dormant, but has the potential to become active again in the future.

The field ranges from Lake Pupuke and Rangitoto Island in the north to Matukutururu (Wiri Mountain) in the south, and from Mount Albert in the west to Pigeon Mountain in the east.

The first vent erupted at Onepoto Volcano 248,000 ± 28,000 years ago. The most recent eruption (about 600 years ago and within historical memory of the local Māori iwi) was of Rangitoto, an island shield volcano just east of the city, erupting 2.3 cubic kilometres of lava. The eruptions have tended to become bigger over time, with Rangitoto making up almost 60% of the field's entire volume of erupted material. All of the volcanoes are relatively small, most being less than 150 meters in height.


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