Taupo ‘tsunami’ after strong shallow quake

A strong tidal surge swept 20 metres inland, destroying boats after a 5.6 magnitude quake struck at a depth of just five kilometres.

Cracks opened up in parkland surrounding the lake. Picture: Facebook.

A tsunami has swept across New Zealand’s Lake Taupo in the North Island after a strong, shallow earthquake hit the area last night.

The 5.6 magnitude earthquake was felt through much of central North Island after it struck 15km southwest of the resort town at a depth of 5 km just before midnight local time (10pm AEDT). It was followed by nearly 200 aftershocks, and a tidal surge that swept up to 20 metres inland, destroying boats belonging to a local tourism operator and sending shallow cracks across the foreshore

Taupo Pedal Boats owners Jess Ratana and Kiripiti Bowden said two of their boats were smashed against the rocks in the surge.

“It’s not something we ever thought would happen – an earthquake, and a lake tsunami. I don’t think anyone would have expected that,” said Ms Ratana.

Taupō Volcano's seismicity has sharply increased overnight with a strong M5.6 earthquake within the volcano's caldera @ 11:47pm NZT, 30 Nov
There has been over 150 quakes in the last 12 hrs. Since April’s unrest started, 1000+ earthquakes have been recorded. Status Alert level 1 pic.twitter.com/S11mVHYiqp

— Hauraki Gulf Weather (@GulfHauraki) November 30, 2022

Taupo’s Mayor David Trewavas, who described the quake as a “doozy,” said his family were woken by the shaking, with his 16-year-old daughter literally being thrown out of bed.

“It was a real rumble and a serious quake. There had been some pre-shakes in the last few days,” he told the Stuff website.

The quake comes after the Volcano Alert at Taupo was raised from 0 to Level 1 in September after hundreds of small earthquakes were recorded this year.

Lake Taupo is the caldera of the Taupo volcano, a super volcano that last erupted 1800 years ago, in 232AD. Before that, it would erupt on average once every thousand years and is now overdue a major eruption.

It seems like the earthquake caused a small #tsunami up near Taupō township. If you live around Taupō we'd be really keen to hear if you've seen any other inundation (see the 'high tide' line in the photo) or other effects (strong currents etc). DM me or let GeoNet know... https://t.co/8Wq6SIaHO5pic.twitter.com/7QJmPLiTSx

— Emily Lane (she/her) (@Emily_M_Lane) November 30, 2022

Raising the Volcano Alert Level to 1 meant “minor volcanic unrest” was causing ongoing earthquakes and ground deformation at Taupō volcano, according to GNS. However vulcanologists said the rise in the level and the increase in “volcanic unrest” did not mean Taupo was at risk of erupting.

GNS seismic duty officer John Ristau told Stuff: “This earthquake and its aftershocks are not an indicator that the volcano is waking up now or that an eruption is on the way. Taupo volcano is still active, although it hasn’t erupted for hundreds of years. There have been many periods of volcanic unrest, with activity levels higher than what we are seeing now that didn’t result in an eruption.”