This morning's earthquake was centred 15km from Christchurch.
A 3.8 magnitude earthquake has shaken awake many Christchurch residents this morning.
The 6.25am quake was centred 15km southeast of Christchurch at a depth of 2km, EQNZ said.
Despite it being rated as "light" by authorities, many residents reported it feeling much stronger than that - particularly for those in and around places including Lyttelton, Banks Peninsula and Waltham.
By 6.45am, just over 5800 people reported feeling it via the GeoNet app.
More than 100 people reported it as feeling "strong" while seven said it felt severe where they were.
Three people said it felt "extreme" when it hit.
"Short, sharp and shallow for Christchurch this morning," GeoNet said.
"That quake was only a magnitude 3.8 but at 7km depth under Lyttelton Harbour, which is why 6000 of you Cantabrians across the city and Banks Peninsula felt it!
"Most people felt it as a light quake, but it was much stronger around Lyttelton."
Many residents took to social media to report that they felt it.
Grant Shimmin said on Twitter: "That was a wee shake! Walking downstairs and felt the whole apartment rattling."
Another local said it "scared the crap out of me" early this morning.
A woman in Waltham said it felt "very strong" there, as did a woman in St Albans.
By 7.15am, four smaller quakes had been recorded in the South Island since the initial bigger jolt early this morning.
At 6.55am, a 2.8 magnitude quake, categorised as "weak" struck 10km southeast of Christchurch at a depth of 11km.
The other "unnoticeable" quakes hit northeast of Milford Sound, northeast of Mt Cook and northeast of Motueka.
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