Some Rotorua locals had an early wake-up call on Monday, after a geyser erupted in Lake Rotorua.
The hydrothermal eruption several hundred metres offshore shot water 20-30 metres in the air around 4am near Ohinemutu.
Ohinemutu neighbour Tawhanga Nopera was woken by a loud rumbling sound.
"I heard my sister get up, then she came in and said: 'There's a big geyser outside, we need to get out of the house'."
The rumbling continued in patches for up to 15 minutes, he said.
"It was weird. It was kinda scary not knowing what it was.
"It was like a really deep earthly rumble. My cousin across the road thought someone was playing really loud sub woofers.
"We've been in this region forever so we're kind of used to the earth moving, things opening up, boiling water bubbling up out of the ground from cracks where it hasn't been before, but nothing like this."
Mr Nopera's sister, Lani Kereopa said on Facebook they rang GNS Science, "and they said 'we'll come down and check it out' but they said it was actually timed with some other things that had happened, so I'm guessing it's related to the earthquakes".
In comparison to Monday morning's 20-30m geyser, Rotorua's Lady Knox geyser regularly erupts, reaching heights of 10-20m (Getty)
The Rotorua Lakes Council said these type of eruptions happen quite regularly but it was usually just a case of bubbling on the surface rather than creating a geyser.
While it was noisy, it was nothing to worry about, says council geothermal inspector Peter Brownbridge.
"It must have been quite powerful to throw up a big column of water as it did but it's nothing for people to be concerned about. We don't see many bigger ones these days although eruptions like this were quite common about eight years ago.
"They blow when the upwards pressure exceeds the capping weight so it can be quite spectacular," he said.