The biggest earthquake to hit parts of New South Wales’s Hunter region in 50 years may have been triggered by coal mining in the region, a geophysicist says.
The 5.0 magnitude earthquake struck the town of Denman at 12.02pm on Friday, prompting thousands of reports of shaking in the following hour, including from people in Sydney, about 171 kilometres to the south.
It was the largest quake in the area in 50 years, but smaller than the magnitude 5.4 quake that devastated Newcastle, 117 kilometres (73 miles) to the east, in 1989, killing 13 people and destroying hundreds of buildings.
Friday’s earthquake caused no major damage to infrastructure or buildings, and there were no reports of injuries, police said.
The New South Wales State Emergency Service said it had received 11 calls relating to minor residential damage and reports of minor infrastructure damage in the nearby towns of Maitland and Muswellbrook.
The SES said the dams in the area were not affected.
Unverified posts on social media showed products falling to the floor at a Muswellbrook hardware store and cracks in the wall of a townhouse, said to have been caused by the quake.
UNSW geophysicist Stuart Clark said the quake was the largest of six to hit the local area, a coal mining hub, in the past 50 years.
A magnitude 5.0 earthquake has been reported near Denman, New South Wales, and Australians living hours away in Sydney have felt tremors.
UNSW geophysicist Stuart Clark said the quake was caused by compressional forces, but the trigger could be coal mining (pictured, a coal truck in Muswellbrook, New South Wales).
“It’s a bit smaller than the Newcastle earthquake, and there was another 5.3 (magnitude) one in 1994,” Associate Professor Clark said.
‘The cause is the compression forces that extend across the continent, but the trigger could be coal mining.’
It warned of aftershocks over the next two days, saying “there could be a cluster of aftershocks typically a bit smaller than this one.”
“They don’t have to follow large earthquakes, but they can.”
A resident of Muswellbrook, about 22 kilometres south of Denman, described the quake as much bigger than “a simple tremor”.
“The whole house shook and then half a minute later it shook again,” the woman said.
Muswellbrook Borough Council mayor Steven Reynolds said he was lying in bed when the house shook violently.
“I’ll tell you what, I thought the roof was going to fall on me,” Mayor Reynolds said.
You couldn’t miss it, it was huge. Here we have the mine explosions and I knew immediately that it was nothing like that.
“I thought it was definitely an earthquake and there could have been serious damage.”
Mayor Reynolds said the area experienced three aftershocks.
Lavis Mitre 10 in Muswellbrook posted a photo of items strewn across its aisles after the earthquake struck the town of Denman shortly after 12pm on Friday.
The quake was reported to have occurred at a depth of 10km and 14km east of Denman, according to the Geoscience Australia website.
A power outage affected an area in South Musswellbrook as a result of the earthquake, which was expected to be restored by 2:30 p.m.
Lavis Mitre 10 in Muswellbrook posted a photo of items strewn across its corridors following the earthquake.
“Well that was epic, wasn’t it?” she captioned the photo.
Sydney residents also reported feeling tremors.
“My apartment just moved in… who else felt it (the earthquake) in Sydney?” posted one.
‘Was there just an earthquake in Sydney or did my building shake just for fun?’
A third said: “I just felt a real earthquake in Sydney. The TV on the wall was shaking, as was the bed I was sitting on. It was crazy!”
Regional New South Wales residents closest to the epicentre, in Mudgee and Gulgong (a two-hour drive west of Denman) reported walls and floors shaking.
“The dogs were barking… I was so scared,” one person posted.
The remains of a chimney that collapsed in the earthquake
Others further west in Dunedoo and someone in Anna Bay, north of Newcastle on the coast, also reported feeling tremors.
Residents in suburban Newcastle also felt the quake.
“The stuff on my table in Swansea Heads shook,” one person commented. “It didn’t even occur to me that it was an earthquake.”
Muswellbrook South Public School posted a message to parents on Facebook at around 12.19pm, saying: ‘Staff and students have been safely evacuated to our Upper Oval pending further instructions.’
Another school, St James’ Primary, posted “we are all fine” but asked parents to come and collect their children.
“We have no electricity, so if you can, please come pick up your children,” the post read.