A second magnitude 4 earthquake shook Christchurch today.
The 4.0 quake, located 5km from Christchurch hit at 7.31pm, 10km deep.
The quake was described as "noisy" by tweeting residents.
This morning a 4.2 magnitude quake shook residents awake about 5.15am.
A 3.4 tremor also struck the city about 8am.
