A 4.8 magnitude earthquake has rattled Christchurch.
Geonet said the shock hit at a depth of 11 kilometres, about 20 kilometres southeast of Darfield, just before 3:30pm.
St John has had no reports of injuries following this afternoon's earthquake.
Its epicentre was near the town of Rolleston.
A Geonet seismologist said early calculations put the quake at 5.0, but those had since been downgraded.