The map showing a 3.9 magnitude earthquake off the coast of Airlie Beach in the early hours of Saturday morning.
The map showing a 3.9 magnitude earthquake off the coast of Airlie Beach in the early hours of Saturday morning. Geoscience Australia

Whitsundays startled by 3.9 magnitude earthquake

UPDATE: With a shudder and gentle jolt, Whitsundays residents were startled by a light 3.9 magnitude earthquake just before 3.30am this morning.

This is the second earthquake in the Whitsunday region in eight days, after a 2.4 magnitude earthquake was recorded in Bowen last Saturday.

Geoscience Australia senior duty seismologist Hugh Glanville said the quake happened in the Coral Sea about 30kms offshore.

"We've had felt reports come in as far south as Mackay, but it was mostly felt in Airlie Beach and surrounds," he said.

Mr Glanville said there may be the possibility of aftershocks in the region.

"There's never anything definite with earthquakes, but given we've had a 3.9 magnitude, it's likely we may get some aftershocks from this one," he said.

In 2016, the region experienced a 5.8 magnitude earthquake, which according to Mr Glanville is "very big"

"We actually deployed monitoring equipment to get a better handle on the aftershocks that were occurring in the area," he said.

Mr Glanville said there are faults in the region that are active, which are the reason behind the earthquakes.

"We expect there are some shallow active faults, for the local or regional area, and stress is being built up and then being released on these fault lines through these small to large earthquakes," he said.

"Generally, it's considered earthquakes with a magnitude of 1,2 and 3 to be small, 3 to 4 is medium and anything from 4.5 and above is when it's considered reasonably large for an Australian earthquake.

"The Australian plate as a whole is moving northwards at seven cm a year, and most of the stress is released along the plate boundary, which is a part of the "ring of fire."

"But some of that stress is transferred into the plates and released through small earthquakes in Australia from time to time."

Mr Glanville said the best way to visualise the stress being released through the shallow active faults is to imagine dropping your phone.

"When you drop your phone, and you get a lot of cracks along the edge of your screen, but then a few cracks will appear in the centre- it's a bit like that," he said.

Mr Glanville advised people to check the Geoscience Australia website for more information.

EARLIER: A 3.9 magnitude earthquake was recorded off the coast of Airlie Beach in the early hours of Saturday morning.

Residents in areas from Calen, Lethebrook, Brandy Creek, Strathdickie, Cannonvale and Bowen were among those who have reported feeling the small earth tremor.

Geoscience Australia estimate the earthquake, which occurred at latitude 148.783 and longitude -19.847, could have been felt 55km away.

The earthquake was recorded at 3.24am, with a depth of 3km.

This latest tremor is the second in little more than a week off the Whitsunday coast.

It follows a 2.4 magnitude earthquake recorded north of Bowen on January 12 at 6.46am, which boasted a depth of 10km.