Trenching near Taupō where researchers are assessing the likelihood of a loop of earthquakes and volcanic eruptions hitting the region. Photo: Supplied
Researchers are digging into the earth in Taupō to assess the likelihood of a "dramatic" loop of earthquakes and volcanic eruptions hitting the region.
The study, funded by the Natural Hazards Commission, is looking at how "twin threats" - earthquakes and eruptions - could set each other off in the Taupō Fault Belt.
Taupō is a supervolcano, capable of erupting volumes of lava, sending matter more than 25 kilometres into the stratosphere and releasing more than 1000 cubic kilometres of volcanic ash that can be carried across the planet by wind.
It is still considered active and while the probability for a future eruption is low, it could still happen - causing significant unrest.
Lead researcher Dr James Muirhead of the University of Auckland, said the supervolcano sat in the heart of faultlines where land was stretching and pulling apart, sparking earthquakes.
"These earthquakes can shake up molten rock deep underground, making it more mobile and explosive," he said.
"As the magma rises, it can also unlock and trigger fault lines, leading to earthquakes. It could be a dramatic feedback loop of seismic and volcanic activity."
There was already some evidence suggesting earthquakes had preceded some eruptions at Taupō, Muirhead said.
His team had been digging a five-metre deep trench at a site on Poihipi Road, which was long enough to cross multiple fault lines in the area.
"Our study is the first to really investigate this in great detail, by carefully examining these layers to see if an earthquake, for instance, occurred immediately before an eruption, or during an eruption, or immediately after one."
Understanding the potential recurrence and magnitude of earthquakes near the Taupō volcano would help inform things like city planning and seismic strengthening of buildings, he said.
"Additionally, if we can find this link between... fault or earthquake processes and volcanism, it can help us better understand and respond to unrest that could happen at Taupō volcano, which is the largest volcano that we have in the country."
Muirhead said an eruption 1800 years ago left much of the area's geological history buried under thick volcanic deposits, so researchers had not attempted to uncover the soil layers until now.
"This massive eruption blanketed the land with metres of ash and pumice, making it nearly impossible to track earlier earthquakes in the soil."
Natural Hazards Commission chief research and resilience officer Dr Jo Horrocks said the findings would help safeguard communities and critical infrastructure from earthquake damage.
"If [scientists] can recognise some earthquake activity as precursors of a volcanic eruption or vice versa, then they can provide that on the spot advice, whether... we've seen some earthquake activity here, so... we might like to take a closer look at the volcano."
The research was being carried out in collaboration with GNS Science and Victoria University.
Muirhead expected the findings to be ready mid-2026.
