A 4.7 earthquake struck the lower North Island just after 2am on Sunday - an hour after a 4.3 quake shook Canterbury.
The 2.05am North Island quake was a deep one - 110 kilometres down - centred 30 kilometres west of Whanganui.
The shallower Canterbury quake, which hit just before 1am, had a depth of 10 kilometres. It was centred 10 kilometres south-east of Christchurch and within five kilometres of Lyttelton.
Geonet says it would have been felt widely across Christchurch.
