Explained: What really caused Adelaide's phantom earthquake
If you were in Adelaide and felt the earth move overnight, you were not alone.
But experts are adament: That was not an earthquake.
Meteorologists say the rumble that shook half the state was caused by a rare weather phenomenon.
Just after 2am two shockwaves about 10 minutes apart shook South Australia.
Geoscience Australia was quick to call it a 1.4 magnitude quake and ground zero was near Willunga.
A vineyard at McLaren Vale was initially identified as the epicentre of the earthquake but after further investigation GeoScience Australia removed it from its website.
'Everything was shaking': Debate over 'earthquake in South Australia overnight'
WATCH: Truckie films woman hanging from P-plate car knocking down cones
The nearest neighbour had no doubt.
"Definitely not thunder 'cause I didn't hear any rain, I didn't hear any thunder," they said.
Seismologists recorded vibrations from Hambley Bridge to Hindmarsh Island.
[36936587|Meteorologist Matt Collopy said sonic booms explained the tremors. Photo: 7 News/]
Meteorologists say what everyone heard and felt were sonic booms caused by thunder from lightning strikes in the Gulf St Vincent, which were trapped under a huge blanket of cloud.
"The thunder that normally resulted occured but that sound was trapped underneatyh that layer and therefore travelled further and sounded louder," meteorologist Matt Collopy said.