New Zealand Shaken by Magnitude 6 Earthquake

Shaking map of the magnitude 6 earthquake that hit South Island, New Zealand, on Sept 20, 2023. (GeoNet/CC BY 3.0 NZ)

New Zealand’s South Island was shaken by a magnitude 6 earthquake this morning.

The quake hit the centre of the island at 9:14 a.m. local time on Sept. 20 at a depth of 11 kilometres (6.8 miles), about 45 kilometres north of the town of Geraldine.

The shaking, described as “strong” by GeoNet, New Zealand’s geological hazard monitoring system, was felt widely throughout the Canterbury region.

Over 14,000 people reported feeling the shake, the monitoring system said.

The earthquake was marked as magnitude 6.2 before it was revised down.

There have been at least 32 aftershocks following the initial quake, the largest of which were two magnitude 3.6 quakes, which caused “weak” and “unnoticeable” shaking, according to GeoNet.

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GeoNet also noted that the magnitude of the earthquake was “relatively small” despite being centred in an area where two active faults meet—the Ben McLeod Fault and the Lake Heron Fault.

However, the area also has no historic records of quakes above magnitude 5.

Local Reaction

Sarah Hussey, a local farmer said the quake had felt much stronger compared to others in the past.

“Previously, the house would just shake. But with this quake it felt like it actually lifted up,” she told 1News.

Her home is around 15 kilometres from the epicentre.

“There’s no damage here, but I thought it was thunder for a start. The house lifted up for a bit,” she said.

“Everyone’s fine and well. We’ve been out checking header tanks and everything seems fine.”

The Timaru District Council said after the earthquake there had been no reports of damage but some facilities would be temporarily closed as a precaution.

“Given the nature of the quake it is unlikely there is any damage, but we are taking a safety-first approach,” the council said on Facebook.

“Engineers are going out to check on our facilities. Some may be closed until they have been cleared.

“This includes but is not limited to Aorangi Stadium, the Farmers car park, Geraldine Cinema, and the lift at the Piazza.”

Meanwhile, Geraldine Primary School said everyone at the school was safe.

“Students are all back in class and happy,” the school said on Facebook.

Today’s earthquake comes on the heel of the 13th anniversary of the 2010 Canterbury earthquake, a magnitude 7.1 that struck the area on Sept. 4 and caused major power outages. No one died as a direct result of the quake.

However, it set off thousands of aftershocks, one of which was the Christchurch earthquake six months later on Feb. 22 that killed 185 people.

Prime Minister Chris Hipkins said earthquakes were always unsettling, particularly for the Canterbury communities given its recent experiences.

“[They’re] a reminder that we live on the edge of the ring of fire, and natural disasters happen in New Zealand and ... we need to always be prepared for them,” he told reporters.