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Onepoto is the name of a volcanic explosion crater (or maar) on the North Shore in Auckland, New Zealand. It is a part of the Auckland volcanic field.

History

Located near the approaches to the Auckland Harbour Bridge, it was created by a series of eruptions approximately 185,000 years ago. The crater first became a freshwater lake, and later became a tidal lagoon when sea level rose to the present level 7,000 years ago after the last ice age. The crater's floor has been reclaimed, with recreational sports fields and a pond, and some parts of the tuff ring were quarried away in the 1950s to provide fill for the Northern Motorway.[1]

Onepoto and neighbouring Tank Farm were fresh water lakes when sea levels were lower using the Last Glacial Maximum. As sea levels rose, the waters of the Waitematā Harbour breached the tuff rings of the craters, becoming tidal lagoons.[2]

See also

• Onepoto Bridge, a bridge offering views of the area
• Tank Farm, a neighbouring crater

References

• Volcanoes of Auckland: The Essential guide - Hayward, B.W., Murdoch, G., Maitland, G.; Auckland University Press, 2011.

• Volcanoes of Auckland: A Field Guide. Hayward, B.W.; Auckland University Press, 2019, 335 pp. ISBN 0-582-71784-1.

External links

• Photographs of Onepoto held in Auckland Libraries' heritage collections.

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