"We encourage people to keep in touch with each other and check on their friends, family and neighbours, especially people who are on their own.''
Quake-hardened Cantabrians went on social media to record their experiences of the rare jolt, which hit at 3.59pm.
"Sharp jolt in Cashmere. Scared the beejesus out of me,'' said one person on the TradeMe community forum.
Another said: "A wobble and a bit of noise ... first one I've felt in months ... I actually said a rude word!''
On Twitter, Amy Bowie wrote: "I was asleep and it woke me up! Bed was going side to side like a jelly''.
GeoNet received more than 700 felt reports of the earthquake, with most rating it as light intensity.