Volcanoes in New Zealand
Our nation sits astride one of the world’s most active tectonic plate boundaries, making it a hotspot for volcanic activity. This unique geological setting not only shapes our stunning landscapes but also plays a significant role in our culture, history, and daily lives.
A Land Forged by Fire
From the Bay of Islands to Otago, volcanoes have left their mark on our landscape. The North Island, in particular, is home to a diverse array of volcanic features, ranging from the cone-shaped peaks of Taranaki and Ruapehu to the expansive caldera of Lake Taupō.
According to GNS Science, we have three main types of volcanoes:
- Volcanic Fields: Such as those found in Auckland and Whāngārei
- Cone Volcanoes: Including iconic peaks like Ruapehu, Taranaki, and Ngauruhoe
- Caldera Volcanoes: Large, crater-like depressions formed by massive eruptions, like Lake Taupō
The Taupō Volcanic Zone
The Taupō Volcanic Zone (TVZ) is the country’s most active volcanic area, stretching from White Island in the Bay of Plenty to Mount Ruapehu in the central North Island. This zone has been the site of some of the world’s largest eruptions in geologically recent times.
The Oruanui eruption from the Taupō volcano, occurring around 26,500 years ago, was the world’s largest known eruption in the past 70,000 years. It ejected approximately 1,200 cubic kilometres of material, dramatically altering the landscape and forming what is now Lake Taupō.
Living with Active Volcanoes
Several of our volcanoes remain active, presenting both opportunities and challenges for nearby communities:
White Island (Whakaari)
Our most active volcano, White Island, regularly emits steam and gases. The tragic eruption in December 2019 served as a stark reminder of the unpredictable nature of volcanic activity.
Mount Ruapehu
Home to popular ski fields, Ruapehu last erupted in 2007. The Department of Conservation (DOC) manages volcanic risk in Tongariro National Park through a comprehensive system of alert levels and warning systems.
Auckland Volcanic Field
The country’s largest city sits atop a volcanic field containing about 53 volcanoes. While currently dormant, the field is considered active, with the most recent eruption occurring only 600 years ago.
Cultural Significance
For Māori, volcanoes hold deep spiritual and cultural significance. Many mountains are considered ancestors or hold important places in tribal histories. The gifting of the peaks of Tongariro, Ngauruhoe, and Ruapehu by Te Heuheu Tukino IV in 1887 led to the creation of our first national park and set a precedent for conservation efforts.
Monitoring and Research
GNS Science, through the GeoNet project, continuously monitors our volcanoes. This network of sensors provides real-time data on seismic activity, ground deformation, and gas emissions, allowing scientists to assess the current state of our volcanoes and communicate this through the Volcanic Alert Level system.
The Science Learning Hub notes that our volcanoes are world-renowned, both for their frequency of eruptions and the volumes of material ejected. This makes them invaluable for international volcanic research.
Volcanic Hazards and Preparedness
While eruptions can pose significant risks, ash fall is the most likely volcanic hazard for most people in the country. The National Emergency Management Agency advises that even small amounts of ash can affect air quality, water supplies, and electrical systems.
Communities near active volcanoes have specific emergency plans in place. For example, the Volcanic Alert Network in Tongariro National Park includes systems to detect eruptions and warn visitors and residents of potential lahars (volcanic mudflows).
Economic and Geothermal Benefits
Despite the risks, our volcanoes also bring significant benefits. Geothermal activity, particularly in the Taupō Volcanic Zone, provides a sustainable energy source. According to the Ministry of Business, Innovation and Employment, geothermal energy accounted for 17.4% of our electricity generation in 2020.
Volcanoes also contribute significantly to tourism. The Tongariro Alpine Crossing, which traverses a spectacular volcanic landscape, is often rated as one of the world’s best day walks.
Looking to the Future
As we continue to live alongside these dynamic natural features, ongoing research, improved monitoring, and public education remain crucial. The challenges posed by volcanic activity also present opportunities for innovation in areas such as geothermal energy, hazard management, and sustainable tourism.
Our volcanoes are more than just geological features; they are an integral part of our natural and cultural landscape. By understanding and respecting these powerful forces of nature, we can better appreciate their role in shaping our land and our identity as a nation.