D’Anastasio said such swarms were “not uncommon” in the area.
“It’s quite common to have this cluster of increased seismicity in Wairoa, and also the whole east coast.”
The quakes were on a known set of fault lines running from the steep hill country northeast of Wairoa to the east coast between Māhia and Gisborne.
The light shaking was likely to taper off in the next few days, and swarms were a good reminder for people to be prepared for a big quake, she said.
“The swarm we’re observing right now so far doesn’t indicate anything concerning, but it’s always a possibility that we can’t predict.”
She said the swarm could be “very upsetting” for people who felt the tremors, but the best thing was to be prepared.
“We live in a very active country in terms of tectonics, and it’s very good to use these swarms as reminders and know what to do in case of large events.”