Three more tremors were recorded on January 23: one at 5:55am, 6:14am and 7:36am according to the tracking station at Armidale. 

South West Rocks’ resident Corrinne Boon said the continuous tremors were concerning.

“We had a really big one at about 9pm. This is so scary. Don't know what to do. Nothing but wait I guess,” she said.

Although data from the nearest tracking station at Armidale shows the tremors are originating to the south of Dorrigo, seismologist Spiro Spiliopoulos from Geoscience Australia said the earthquakes have been difficult to precisely locate because of their small magnitude.

“We’re still working on the location,” he said.

“These earthquakes measured a magnitude 2.5 on the Richter Scale, so they must have originated very close to where the people were feeling them.”

The first of the four tremors, occurred at 10.10am on Saturday, January 20.

Ms Boon said all of the windows in her house on Flinders St shook as though a large truck was passing closely by.

Later in the morning, at 11.46, she says there was a much heavier tremor.

That afternoon at 4.57pm, there was a third quake, followed by a fourth at 4.21am on Sunday.

Mrs Boon told the Argus the last tremor particularly unnerved her.

“They were getting stronger each time and I was worried it was a preliminary to a bigger earthquake – sometimes you hear reports of minor tremors leading into a major earthquake,” she said.

“It was just so out of the ordinary.

“It’s really bizarre – we don’t have earthquakes here and all of those in two days.”

Mr Spiliopoulos said although experts are still unsure as to the cause of the latest tremors, earthquakes in the region were uncommon but not rare.

“Australia has a low level of background seismicity,” he said.

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“In the last 20 years, there has been 10 earthquakes within a 100km radius of South West Rocks, including the four on the weekend.”

Mr Spiliopoulos said it is difficult to forecast whether the earthquake activity will continue and if so, for how long.

“Sometimes we call it a swarm of earthquakes – it’s unpredictable,” he said.

“We’ll continue to monitor and if anything further happens, we’ll report it on our website.”

If you experience any earthquake activity and wish to report it, you can do so via www.ga.gov.au