A magnitude 3.7 earthquake occurred in Canterbury at 2.59am on Monday.
It was the first for almost 24 hours and was centred 10km east of Christchurch at a depth of 10km.
A magnitude 3.4 quake was recorded at 2.48am on Sunday, which was also 10km east of Christchurch, at a depth of 12km.
A magnitude 4.5 quake also occurred on Monday, at 6.46am. It was 20km east of Christchurch, at a depth of 12km.
It was followed by a magnitude 4.0 quake at 8.31am, 20km east of Christchurch, at a depth of 9km.