Checks for damage after big quake rocks south

Officials are today checking for damage after a huge earthquake rocked parts of the South Island last night.

People ran from restaurants in Queenstown as buildings shook and lights went out. Phone lines went down as people overloaded the lines.

GNS recorded the quake as 7.8 magnitude at 9.22pm followed 20 minutes later by a 6.1 magnitude.

The quake was followed by violent aftershocks felt as far north as Wellington.

GNS seismologist Bill Fry said the aftershocks would last for the next few weeks.

Mr Fry said there have been a series of after shocks measuring five on the Richter scale and a ton of "over fours" already.

Click here for reader experiences of the earthquake.

The first of the quakes was 5km deep and was centred 90km north-west of the Southland town of Tuatapere.

Prime Minister John Key is visiting Invercargill today on a scheduled trip and said any government response would depend on damage, which had yet to be assessed.

"If there is significant damage or something that I can usefully be deployed to I will certainly go and have a look and lend a hand," Mr Key told Radio New Zealand.

"All the feedback we've had so far is while it's been a large quake, certainly at this point no reported loss of life which is fantastic, and no great reports of damage."

Damage checks

Southland Civil Defence emergency management group were today carrying out an aerial survey to check for damage.

Group co-ordinator Neil Cruickshank said that while there had been no reports of significant damage overnight, checks of bridges and roads would be undertaken this morning.

"While there has been disruption to electricity supplies, power companies reported no major problems, and the rail network is reported to be undamaged. Telephone services are operational," he said.

"Previous experience suggested that the quake would have triggered land slides in remote areas of Fiordland.

"There may also have been minor damage to buildings, such as falling chimneys."