Ms Dalziel told the Herald just before 7am there had been no new reports of damage, road closures or other quake-related problems overnight.
She would now hear from seismologists about the latest aftershock in a sequence of more than 15,000 since the city was first rattled by the 7.1 Darfield earthquake in September 2010, and almost five years to the day since the 6.3 magnitude jolt that killed 185.
"I'm getting a briefing from GNS this morning. They are saying this is not unexpected in terms of the sequence of events ... there have been more than 50 aftershocks over five [magnitude] since September 2010. I just think it's been a bit of a shock to people because there hasn't been one for a while.
"My message is just be aware that people who are feeling vulnerable need a bit of support. Just look after each other. I think that Christchurch has shown we are very good at doing that."
