Maps show big risk of damaging aftershocks on Kaikoura coast, small chance in Wellington
Maps from GeoNet and GNS Science show much of the South Island's northeast coast has little chance in the next 30 days of avoiding more damaging aftershocks of last week's magnitude-7.8 quake.
In contrast, the risk of damaging aftershocks in Wellington is put at only around 5 per cent, while Christchurch isn't even included in the aftershock probability forecast area.
The maps were produced before the magnitude-5.7 quake at 6.13pm on Tuesday, which was centred 15km southeast of Culverden and was only 7km deep. That quake was classed as severe and many people in Christchurch reported being shaken by it.
Aftershocks were happening throughout a broad area surrounding the faults that ruptured in the main earthquake, GeoNet said.
Most of the aftershocks were near those faults, but a small number were as far away as the lower North Island.
"Our current forecasts indicate that it is likely ... aftershocks near these faults will continue, but for the frequency of aftershocks to decrease with time. We are already seeing this happen," GeoNet said.
"The area nearest the faults has a probability of 80 per cent or more for damaging shaking in the next 30 days. In comparison, the probability of damaging shaking in the Wellington area (the darker blue tones) is less than 10 per cent."
It was still possible for Wellington to have more shaking similar to that experienced during the main quake. Wellington was already a high seismic risk area and the M7.8 quake had increased that risk.
Christchurch's aftershock probabilities were not greatly affected by the M7.8 earthquake, GeoNet said.
"We understand that aftershocks can be upsetting for some people. These feelings are completely normal."
As well as seeking support with friends and family, the All Right? hotline was a great resource where people could talk about any anxieties or concerns they had about the earthquakes. The phone number is 0800-777-846.