ARMIDALE residents were left shaken on Friday night after two minor earthquakes hit the New England region.
According to Geoscience Australia, the 4.2-magnitude quakes were 17km deep.
It was the strongest earthquake measured in the area since 1983, when there was a 4.6-magnitude tremor.
The epicentre was about 20km west of Manilla and the tremors were also felt in Armidale, Tamworth, Barraba, Gunnedah, Uralla and Inverell.
The two tremors hit within minutes of each other, with the first at 9.31pm and the second one occurring 90 seconds later.
Armidale Police said they fielded dozens of phone calls in relation to the tremors but had no reports of damage.
Geosciences Australia seismologist Jonathon Bathgate said earthquakes of such a size do not usually cause damage, and that the New England region has had a few earthquakes in the past 100 years.
“There’s been about 13 of this sort of magnitude in that area in these sort of times,” he said.
Mr Bathgate said there had already been two confirmed aftershocks of very low
magnitudes in our region.
“The first one came around two minutes after the second quake and then the next one was 20 minutes after that, but I’m not sure if anyone would have felt them,” he said.
“We can’t predict earthquakes but generally what happens with earthquakes of this size is there is some aftershock activity just as the fault that has moved in an earthquake it sort of resettles down, you’ll get some smaller tremors and a lot of those will go unnoticed by the public.”
Mr Bathgate said aftershocks could continue this week and gradually weaken.
While the 4.2-magnitude quakes were measured across the region, the two aftershocks were only measured in Armidale.
Mr Bathgate says it is all to do with the underground plates Australia sits on.
“The continent’s moving north at about seven centimetres every year and that just builds up stresses across the rocks. So the overall process is the same for big earthquakes,” he said.
In the aftermath of the quake, the State Water Corporation has checked the Keepit, Pindari, Chaffey, Copeton and Split Rock dams for structural faults.
“All of these dams need to meet seismic safety standards,” spokesman Tony Webber said.
“Our safety inspectors have confirmed there’s no damage. They’re operating as normal.”
There were rumours the quake had caused structural damage to Keepit Dam, where the epicentre of the quake was, but Mr Webber said the rumours had proven false.
“We’re not exactly sure where it came from,” he said “We’re theorising it’s come from Facebook and social media. There certainly seems to be uncharacteristic media attention.”
The Express’ website received many comments from locals about the earthquake. Some said that they definitely felt the earthquake, such as Col who commented: “It shook the crap out of my house in Uralla, 2 tremors about 1 minute apart. All seems good though and no damage as far as I could see in the dark.”
Another local resident, wendlesB, wrote: “I’m so glad to hear that it wasn’t just my imagination when my house shook to the rafters!! I am in town (Armidale) and it really gave my little cottage a shake-up! Glad to hear that there was no damage, though I have to say, I was not keen on going outside in the cold alone to check for cracks ... that can wait until the morning!”
Sarah added: “I’m up in Armidale, staying in a caravan alone and it shook violently. When I called friends in Sydney to say that I think I just experienced a very small earth quake, they all thought I was crazy! At least now I know I’m not!”
Jimbo wrote: “ We’re in Armidale and the quake rattled our windows. At first thought maybe was a sonic boom but then decided was a small earthquake. That thought was confirmed in the morning news on TV and by USGS website that plots all significant earthquakes worldwide.”
CCCMikey confirmed that the quake was also felt at Black Mountain.
“I felt it at Black Mountain, too - the first rocked the cantilevered coffee table slightly, the second I felt as four jolts through the couch. Jumped onto Twitter with a search for earthquake, and sure enough within a few minutes come the reports of the earthquake; along with a wisecrack of ‘Tsunami Warning for the Peel River!’” he commented.
Others didn’t notice anything at the time with Bush bunny writing, “We were in the Ex-Services Armidale and customers warned there had been an earth tremor and staff were on the alert but we felt nothing, it is a substantially built building though.”
Another reader, Diana said: “We must be too far up the mountains as we felt nothing here at Tenterfield.”
Let us know your earthquake
experience in the comments