A magnitude-4.5 earthquake struck 40km west of Tuatapere yesterday and a 6.4 tremor was recorded east of New Zeland last night.
The "strong" quake rumbled in at 6.21am and was at a depth of 5km, according to GeoNet.
There were no reports of damage. GNS duty seismologist Anna Kaiser said there had been quite a lot of activity in the area.
"We are stll seeing aftershocks from the [7.8-magnitude] Dusky Sound quake in July 2009."
Heightened activity from a nearby fault was related to the subduction zone – the Australian plate was being pushed under the Pacific plate, she said.
Meanwhile, a strong earthquake struck in the ocean off the east coast last night.
The magnitude 6.4 tremor hit at 10.26pm, GNS Science said.
It was centred 730km north east of Whakatane and was 33km deep.
GNS described the quake as "severe''.
- The Southland Times
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