Aftershocks to Wednesday's 7.8 magnitude earthquake in Fiordland are becoming weaker and more frequent, a sign that the area is settling down, says a GNS Science seismologist.
The area has been hit by more than 100 tremors since the big one.
The latest, at 3.30am was centred 90km west of Te Anau and measured 5.4 on the Richter scale.
Several dozen quakes yesterday measured more than magnitude 3.
"What's happening is that the stress that was given off by the energy that was released in the first earthquake is redistributing itself and everything is trying to re-equilibriate," seismologist Bill Fry told Radio New Zealand.
Wednesday's 7.8 quake was the biggest recorded in the world this year.