Canterbury continues to be jolted by earthquakes, with four felt in the region on Friday.
A sharp 4.6-magnitude quake occurred at 5.56pm, followed by one measuring 3.7 at 6.17pm.
Both quakes were 20km southwest of Christchurch at a depth of about 9km.
Earlier, a 2.9-magnitude quake occurred 9.32am within 5km of Christchurch at a depth of 5km.
Another quake at 7.32am measured 4.5 and was situated 20km north-west of Oxford at a depth of 9km.
GNS Science says residents described the quake at 5.56pm as strong and sustained.
There have been many aftershocks following a 7.1-magnitude quake in September last year which caused widespread damage in the region.