Cantabrians have been advised to check on friends and neighbours, after the first strong earthquake to rock Christchurch in months.
No reports of injuries or emergency calls were received after the magnitude 4.1 quake this afternoon.
The quake was located 25km south-west of Christchurch, near Darfield, at a depth of 7km.
GeoNet gave the tremor a 5 rating for Mercalli Intensity - the power with which it was felt on the earth's surface.
St John South Island Communications Advisor Ian Henderson said the first sizeable quake felt in Canterbury for some time may have come as a surprise or shock to some.