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In short:
Four earthquakes have struck near the town of Port Hedland in just over 12 hours, labelled an earthquake "swarm".
Geoscience Australia says the first 3.1-magnitude quake was likely a "foreshock" ahead of the later 3.8-magnitude tremor and further aftershocks.
What's next?
Residents can expect further aftershocks but they are not expected to be significant.
An earthquake "swarm" has shaken the Pilbara mining town of Port Hedland with four minor earthquakes recorded in just over 12 hours.
A magnitude 3.8 earthquake struck the town, 1,600 kilometres north of Perth, followed by two aftershocks registering magnitudes 3.6 and 3.5.
Geoscience Australia described an early morning 3.1-magnitude quake 70km south of the town as a "foreshock".
The two larger quakes struck the remote Aboriginal community of Strelley, 50 kilometres south-east of Port Hedland.
The fourth quake was recorded close to the centre of Port Hedland Thursday afternoon.
Port Hedland resident Nick Roberts said the largest quake, which hit at 11:39am local time, felt as though a truck had run through his building.
"It was very short and sharp," he said.
All four earthquakes were relatively shallow at a depth of 10 kilometres.
No significant damage has been reported as a result of the earthquakes.
Five quakes over 3.0-magnitude in past month
In the past decade 13 earthquakes over magnitude 3.0 have been recorded within 100 kilometres of Port Hedland.
Five of those were recorded in the past month, with four already today.
Geoscience Australia described the series of events as an earthquake "swarm".
Senior seismologist Dr Hadi Ghasemi said it was not unusual to have small earthquakes in the region, but it was not typical to have an aftershock larger than the initial earthquake.
"Aftershocks are always a possibility," he said.
"But if there's an aftershock, generally speaking, the aftershock would be much smaller than the main shock itself."
Dr Ghasemi said given the first earthquake was weaker than the second it could be classified as a "foreshock".
"We know that there are a small fraction of earthquakes which are followed by a larger nearby earthquake," he said.
"It's not that frequent, but it's not uncommon."
Possibility of mining-induced quakes
Last month Port Hedland residents were shaken awake by another earthquake 30 kilometres to the south-east registering magnitude 3.5.
On Saturday June 8, residents detailed hearing a loud bang, followed by several seconds of shaking.
The region is well known for its mining industry, with major iron ore and lithium producers operating in the region.
Dr Ghasemi said it had been established that mining activity could induce earthquakes, but acknowledged the region had a recorded history of earthquakes over an extended period of time.
"In this particular case we cannot really say for sure [what was the trigger]," he said.
"Looking at the background of the region you do expect small earthquakes."
Sunday marks the 5th anniversary of a 6.6-magnitude earthquake which struck off the coast of Broome in 2019.