Auckland Volcanic Field
From Wikipedia, the free encyclopedia
The Auckland volcanic field is a monogenetic volcanic field in the North Island of New Zealand. Basaltic in nature, it underlies much of the metropolitan area of Auckland. The field's many vents have produced a diverse array of explosion craters, scoria cones, and lava flows. Still active, the field is is likely to erupt again within the next "hundreds to thousands of years" (based on past events)[1], a very short timeframe in geologic terms.
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[edit] Volcanoes
The first vents erupted at the Domain, Albert Park and St Heliers between 60,000 and 140,000 years ago. Since then some 49 vents have erupted, though each eruptive vent has generally only had a geologically short period of activity. The most recent eruption (about 600 years ago and within historical memory of the local Māori iwis) was of Rangitoto, an island shield volcano just east of the city, erupting 2.3 cubic kilometres of lava only centuries ago. Each volcanic eruption has tended to be bigger than the previous, 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.
[edit] Human usage
Several of the volcanic cones were occupied by substantial Māori pa before European settlement, and many terraces and other archeological remnants are still visible. Many of the cones have been levelled or strongly altered - in small part due to the historical Māori use, but mostly through relatively recent quarrying of construction materials (especially scoria). However several of the remaining volcanoes are now preserved as landmarks and parks.
Local councils made submissions to the New Zealand government that the volcanic field's unique natural and cultural features justify its inclusion in New Zealand's tentative list of World Heritage Site candidates. As of 2007, only barely more than 2% of more than 800 World Heritage Sites worldwide are in this "mixed" category.
[edit] List of volcanoes
The volcanoes within the field include:
- Lake Pupuke
- Tank Farm (or Tuff Crater)
- Onepoto
- Mount Cambria
- Mount Victoria
- Duders Hill
- North Head
- Albert Park
- Auckland Domain
- Rangitoto
- Browns Island
- St Heliers
- Taylor Hill
- Orakei Basin
- Little Rangitoto
- Mount Albert
- Mount Roskill
- Three Kings
- Mount Eden
- Te Pouhawaiki
- Mount Saint John
- Mount Hobson
- One Tree Hill
- Hopua
- Mount Smart
- Mount Wellington
- Panmure Basin
- Pigeon Mountain
- McLennan Hills
- Mount Richmond
- Mangere Mountain
- Mangere Lagoon
- Puketutu Island
- Waitomokia
- Pukeiti
- Otuataua
- Maungataketake
- Robertson Hill
- Pukekiwiriki
- Styaks Swamp
- Green Hill
- Otara Hill
- Hampton Park
- Pukaki
- Crater Hill
- Kohuora
- Matakarua
- Manurewa
- Ash Hill
[edit] References
- ^ Contingency Plan for the Auckland Volcanic Field (from the Auckland Regional Council website)
- Lloyd Homer, Phil Moore and Les Kermode. Lava and Strata: A guide to the volcanoes and rock formations of Auckland, Landscape Publications and the Institute of Geological and Nuclear Sciences, 2000. ISBN 0-908800-02-9.
- Christina R. Magill and K.J. McAneney. Probabilistic assessment of future vent locations and eruption styles for the Auckland Volcanic Field, New Zealand, Proceedings of the International Association for Mathematical Geology 2003, Portsmouth, UK, September 7-12, 2003.
- Christina R. Magill and Russell Blong. Volcanic risk ranking for Auckland, New Zealand. I: Methodology and hazard investigation, Bulletin of Volcanology, Volume 67, Issue 4, Apr 2005, Pages 331 - 339, DOI 10.1007/s00445-004-0374-6, URL http://dx.doi.org/10.1007/s00445-004-0374-6 accessed 2006-07-14.
- Ernest J. Searle, revised by R.D. Mayhill. City of Volcanoes: A geology of Auckland, Longman Paul, 1981. First published 1964. ISBN 0-582-71784-1.
- Sharon R. Allen, Vivienne F. Bryner, Ian E. M. Smith, Peter F. Ballance. Facies analysis of pyroclastic deposits within basaltic tuff-rings of the Auckland volcanic field, New Zealand, New Zealand Journal of Geology and Geophysics abstracts, New Zealand Journal of Geology and Geophysics, 1996, Vol. 39: 309-327 0028-8306/96/3902-0309 $2.50/0 (c) The Royal Society of New Zealand 1996.
[edit] External links
- NZ Institute of Geological and Nuclear Sciences Auckland Volcano page
- Auckland Regional Council - The Volcanoes of Auckland
- NZ Herald opinion column on World Heritage listing
- Smithsonian Institution's Global Volcanism Program - Auckland Field
- Facies analysis of pyroclastic deposits within basaltic tuff-rings of the Auckland volcanic field
- University of Auckland's Geology of Auckland page (with interactive maps, requiring Apple QuickTime).
