Aftershocks are being felt from a 5.4 magnitude earthquake in Western Australia's south that rattled houses and woke people up more than 300km away in Perth.
It struck the Lake Muir area just after 5am on Friday and followed a 3.8 magnitude earthquake on Thursday night.
Geoscience Australia senior seismologist Johnathan Bathgate said the epicentre was potentially damaging and the agency had received more than 2500 reports from the public who had felt it, with some saying it had caused cracks in buildings.
More than 600 seismic events have been recorded in the area since a 5.7 magnitude quake on September 16.
After that event, a farmer discovered hundreds of metres of large surface cracks in his paddock, where the agency will visit next week to do mapping and put together a picture of a fault scarp in the landscape.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Australia's massive tectonic plate is moving north by about seven centimetres a year and when it collides with other plates, stress builds up, causing faults, Mr Bathgate said.
He said Lake Muir, in WA's South West region, was not usually particularly active but a seismic zone to the north in the Wheatbelt region was the most active in Australia.
That zone includes Meckering, which was flattened by a 6.78 quake in 1968.
"We expect the aftershocks to continue - we're not sure for how long," Mr Bathgate told AAP.
"We might see more quite strong ones or it could peter out.
"That could be it for another 1000 years."
While there has clearly been a significant cluster of activity in the Lake Muir area, the high number of detections can partly be explained by more equipment being sent to the area to measure it.
