Christchurch got its biggest shake in four months last night when a 4.8-magnitude earthquake struck 20 kilometres east of the city.
The tremor came just after 5pm at a depth of 8km.
It followed a 4.1-magnitude tremor centred near Rolleston at 9.35am.
It was followed by several smaller quakes during the day including a mag-3.6 at 7.24pm, just 8km keep, and two late evening shakes which woke many in the city.
The first at about 11.30 was a mag-3.4 at 8km deep, followed about 15 minutes later by a mag-3.2 at a depth of 9km. Both were centred at sea off the Southshore coastline.
Geonet duty seismologist Caroline Little said a lot of earthquakes were centred in Pegasus Bay, near where the December 23 quakes had struck.
Yesterday's shakes were within expected aftershock patterns, she said.
"It's the biggest quake since January 15, and we can expect a few of these larger ones.
"It's just what's going to happen as Christchurch settles."
Police said there had been no reports of damage in the city.The quake prompted a flurry of responses on Twitter.
"Christchurch, the only place where you can watch Avengers in 4D," tweeted web designer Mike Walker, possibly from inside a city movie theatre.
Sel Leigh tweeted: "Hmmm can think of better places to be during #eqnz than on hands @ knees scrubbing toilet. Was like being on a boat."
Paula Brooksby posted: "That was a bit weird, walking round the house & all of a sudden the fish tank water slosh everywhere ... but I didn't feel it."
- © Fairfax NZ News
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