Factbox: Christchurch quakes

Christchurch was repeatedly hit by earthquakes and aftershocks in the past year.

Christchurch was repeatedly hit by earthquakes and aftershocks in the past year.

* September 4, 2010: 7.1 quake, 11km deep, 40km west of Christchurch

* December 26, 2010: 4.9, 12km deep, within 5km of Christchurch

* February 22, 2011: 6.3, 5km deep, 10km southeast of Christchurch

* June 13, 2011: 6.3, 6km deep, 10km southeast of Christchurch

* December 23, 2011: 5.8, 8km deep, 20km east of Christchurch

* December 23, 2011: 6.0, 6km deep, 10km east of Christchurch