Victoria appears to have escaped widespread damage and no injuries have yet been reported after a major earthquake shook Melbourne.
Geoscience Australia said the magnitude 5.8 earthquake hit the Mansfield region, about two hours north-east of Melbourne, about 9.15am. Emergency services reported tremors as far north as Dubbo and Sydney, both about 700km from the epicentre.
There have been three aftershocks recorded since then, with experts warning there could be more in the following days and, even months.
The state’s emergency services fielded dozens of calls and 35,000 properties briefly lost power, but deputy premier James Merlino said most reports of damage were minor and there were no reports of injury at this stage.
“Beechworth Hospital lost power, but have back-up,” Merlino said. “Building damage has been reported across Kensington, Ascot Vale, Parkdale, Prahran, Balwyn, Elsternwick, Northcote and West Melbourne… 46 reports in total.”
Helicopters have been dispatched to assess the situation, and Emergency Management Victoria has issued a state-wide warning at the ‘watch-and-act’ level.
The tremors lasted for about 20 seconds though some areas reported they went for longer. It was strong enough to shake a building in Chapel Street in the inner-Melbourne suburb of Prahran, causing the top of the wall to rattle free and bricks to smash on the ground below.
Tim Mcdonagh, the managing director of Betty’s Burgers in the damaged building, said it was surreal, describing it as a “catastrophe” in already unusual circumstances.
Mcdonagh said it was lucky no staff members were on site at the time of the earthquake.
“If this was a non-lockdown period, someone would have been underneath that,” he said pointing to the debris on the pavement.
The resident of an apartment above the restaurant was able to safely evacuate.
In Mansfield, locals described the moment the earthquake hit the township.
“It started slow, built up and everyone was nervous. We heard this rumble, rumble like a big truck coming through the building,” said Rebecca Douglas, owner of the Witches Brew Cafe.
Dr Januka Attanayake, the research lead with the University of Melbourne’s earthquake seismology earth sciences unit, said preliminary estimates had the earthquake as a magnitude 5.8 to 6.0 and that aftershocks could occur for months.
It is the strongest earthquake recorded in Victoria since a magnitude 5.7 event was recorded at Mount Hotham in May 1966, and the first recorded since a magnitude 5.4 earthquake in the Gippsland town of Moe in 2012.
“If these preliminary estimates are correct, it is probably the largest earthquake we have felt around Melbourne in the last 175 to 200 years,” Attanayake said. “If it’s a magnitude 6.0, it’s the first in hundreds of years. This is the first earthquake of this magnitude I have seen here during my lifetime, and it has probably not been seen during the lifetime of several generations.”
The Australian prime minister, Scott Morrison, contacted the Victorian premier, Daniel Andrews, from New York to discuss the incident.
Morrison said the federal government would provide any support necessary.
“At this stage, we have had no reports of serious injuries or worse and that is very good news and we hope that good news will continue but we will get further reports as the night unfolds here in the United States,” he said.
“It can be a very, very disturbing event for an earthquake of this nature … They are very rare events in Australia and as a result, I am sure people would have been quite depressed and disturbed by that, particularly in the most immediate area affected.”
Attanayake said there are fault lines “all over the Australian continent” and that earthquakes themselves are not rare. But ones of the magnitude seen on Wednesday are.
“We record about 400 earthquakes less than magnitude 2.5 every year,” he said. “So earthquakes are not exceptions.”
Usually, Attanayake and his team would put out more seismometers in the aftermath to try and detect aftershocks, which can last for months, but due to Covid-19 travel and work restrictions this was not possible, he said. Two significant aftershocks of 2.5 and 3.0 have already been detected by existing seismometers. However, most aftershocks will not be felt.
“It’s important work because if we can detect aftershocks we can detect the fault area that ruptured,” he said. “We need to know this information for proper future hazard analysis. It helps us detect expected ground motions of earthquakes going forward. This is essential information for engineers building city structures in future, as we can for example say how much ground motion can be expected at a given location over the next 50 years.”
The earthquake was felt as far as New South Wales, the ACT and Tasmania. Attanayake said according to the first reports, the earthquake was felt around a 600km radius.
Across Melbourne, apartment dwellers ran out on to the street, concerned their building was collapsing.
Federal MP Michael McCormack also reported feeling the tremors in the New South Wales town of Temora, 85km north of Wagga Wagga and 370km north of the epicentre in Mansfield.
NSW state MP Helen Dalton also reported feeling a “minor earthquake” in Jerilderie, just north of the Murray River.
It was also reportedly felt in Launceston in northern Tasmania, about 700km to the south across the Bass Strait.
Earlier, Australian earthquake observatory the Seismology Centre said there had been a magnitude 5.3 earthquake in Gippsland, in eastern Victoria, with an epicentre in the high country just north of Woods Point, about 100 km east of Melbourne.
Global earthquake monitoring site Earthquake Monitor listed it as a magnitude 5.6 earthquake.
Dr Adrian McCullum, a senior lecturer in geotechnical engineering at the University of the Sunshine Coast, said these earthquakes occur because the continental plate on which Australia sits is moving north at about 7cm per year.
“This builds up compressive stress within the Australian plate,” he said.
“This stress is occasionally released – resulting in an earthquake – typically along pre-existing fault lines, where the earth has sheared (and can shear again) because of these stresses,” he said.
Inspection of the geological maps of Victoria shows a large number of faults in the Mansfield, Victoria region. “Thus it appears like an area where the release of compressive stress via an earthquake might be probable,” McCullum said.
Additional reporting by Donna Lu.