A massive aftershock measuring 6.2 on the Richter scale has this morning jolted the lower South Island with a quake striking at 10.28am and lasting for about 30 seconds.
GNS Science duty seismologist Bryan Field said the latest shake was a 6.2 magnitude centred 50 kilometres west of Milford Sound at a depth of 5km.
"This is normal activity after a big earthquake," he said.
"It has been a busy period but statistics say for every quiet patch you must have a busy patch down the track. It's all normal stuff."
Earlier this morning a quake measuring 6.7 on the Richter scale shook the South Island and while felt strongly there were no immediate reports of serious damage or injury.
Betty's Liquor Store manager Christine Gilbert said seven bottles, worth $350, were lying broken on the floor when she arrived at work at 7.45am this morning. Another 12 bottles were on the ground but unbroken.
The mid-morning after shock had caused some excitement but no damage.
"We were in here holding stuff up. Things were swinging like a Christmas tree."
GNS Science duty seismologist Mark Chadwick said that quake, which struck at 1.29am, was centred 60km from Milford Sound at a depth of 24km.
"Fortunately it's slightly offshore from Fiordland so there's not too much infrastructure down there to damage," he said.
Transit New Zealand Southland area engineer Peter Robinson told The Press that there was no visible signs of damage to the Homer Tunnel or to bridges on State Highway 94 between Te Anau and Milford.
Snow forecast for the area was more of a concern, he said, and the road may be closed at 5.30pm today depending on whether a predicted storm hit.
Southland Civil Defence officer Tom Shaw said civil defence staff at Milford had inspected the area immediately after the quake and there were no signs of damage to the hydro generator, water and sewerage systems or buildings. Another check this morning confirmed there was no damage.
The earthquake was felt very strongly in that area as well as across the region and further afield, he told NZPA.
Police in Te Anau and Queenstown had no reports of damage.
The lower South Island was shaken by a 7.3 magnitude quake on September 30, which was centred 220km north-west of Auckland Islands at a depth of 12km.
The biggest quake in recent times was a 7.4 magnitude shake on August 21, 2003.
Invercargill Civil Defence officer, Bill Obers, said he had not received any reports of structural damage in the immediate aftermath of the quake.
Staff from the Southland Civil Defence Emergency Management Group were also monitoring the situation.
A spokesman from the police southern communications centre in Christchurch said police had received calls from many people in the lower South Island since the quake, but no damage or injuries had been reported.
- The Press
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