Muswellbrook and Denman felt further tremors on Saturday after the region was shaken by the biggest earthquake in 20 years on Friday afternoon, August 23.
Weak seismic activity was felt early Saturday morning at both townships before a noticeable 4.5-magnitude tremor was recorded just after 6.30 a.m., not far from the epicentre of yesterday's 4.8-magnitude quake.
Two other aftershocks followed shortly after before 7.35am, according to records from Geoscience Australia, before reports of another 4.5-magnitude quake about 4.30pm.
There were widespread power and water outages in Muswellbrook during the afternoon, the local council advised via its social media accounts. Services were gradually returned from around 3.30pm.
Geoscience Australia's senior seismologist, Dr Hadi Ghasemi, said the organisation was flooded with more than 1600 field reports of tremor within a few hours of Friday's event, some from hundreds of kilometres away, as the movement was felt as far as Wollongong, Dubbo and Tamworth.
"There is always a possibility that the aftershocks will continue for the weeks to come, but as a general rule of thumb, the larger aftershocks tend to occur at the earlier stages," Dr Ghasemi said.
Schools and courthouses were evacuated, businesses closed, and more than 2500 people were without power in Muswellbrook on Friday, but emergency services confirmed there were no reports of injury.
The epicentres of the initial quake and at least two aftershocks appeared to be at BHP's Mt Arthur Coal mine in Muswellbrook.
