Experts are mystified by an earthquake swarm off the coast of Northland, normally a seismically quiet area.
Since Boxing Day, Northland has experienced 22 earthquakes.
GeoNet's website shows during the same dates the year prior (December 26 2017 to January 15 2018), the region saw only three quakes.
GeoNet seismologist John Ristau says the flurry is "very unusual".
"I don't know when was the last time we saw this type of swarm."
Engineering seismologist Chris Van Houtte agrees the quakes are "definitely uncommon".
"There have been a few quakes in the area that we haven't seen before, so it's uncommon. Definitely uncommon."
Because the activity in the area is normally so low, Dr Van Houtte says we know very little about quakes in the Auckland and Northland area as there's not much data.
Dr Ristau explains the earthquakes as a "swarm", and says while unusual, they're not usually anything to be afraid of.
- Video shows dramatic landscape changes following Kāikoura earthquake
- Upper North Island rattled by earthquake swarm
- Hikurangi megathrust quake could be more destructive than Japan's with 30m waves
"New Zealand sits on the boundary of two plates, so mostly earthquakes are going to happen along these plates. Northland is about as far away from them as you can get, but it will still have activity."
He goes on to say the most likely scenario is that it's a swarm.
"So you'll get a few earthquakes, then everything tapers off."
Both seismologists agree that these "swarms" are not necessarily a reason to be afraid.
Dr Van Houtte says whenever there are earthquakes, people will be concerned that there will be another, but that the Northland region has one of the lowest seismic activities in New Zealand.
Dr Ristau backs this statement up, saying out of 19,500 earthquakes throughout New Zealand in 2018, only 32 occurred in Northland.
The quakes are too small to pose a tsunami risk says Dr Ristau, and Dr Van Houtte agrees.
However, Kiwis are still encouraged to be prepared.
"We're in a seismically active country. Earthquakes can happen at any time, and in any place, so people need to be prepared," Dr Van Houtte says.
For information on how to prepare for an earthquake or tsunami, visit www.happens.nz