image captionThe third earthquake struck on market day in the Bedfordshire town
An earthquake has been felt in Leighton Buzzard for the third time in two weeks.
People wrote on social media they had felt their houses “jolting and shaking” at about 09:30 BST.
The British Geological Survey (BGS) confirmed the 3.0-magnitude tremor happened just north of the Bedfordshire town.
A 3.5-magnitude earthquake was felt by residents on 8 September, followed by a 2.1 magnitude tremor on 13 September.
Matt Stewart, who lives in Eggington, about 1.5 miles (2.4km) from Leighton Buzzard said the tremors “almost shook me out of bed”.
‘A whoosh and a boom’
“It was as big as the first one, I think,” he said. “My wife ran downstairs and said, ‘oh no, not another one’.
“It felt like a whoosh and then a boom coming up through the earth, then it shook the house and a couple of pictures fell off the wall upstairs, like the last time.”
image captionThe British Geological Survey has released seismograms of the latest earthquake
Mr Stewart described it as “a horrible feeling”.
“You’re just not in control and I’d like to know what’s going on, as this is the third one – it’s very strange.”
image captionThe small town of Leighton Buzzard has experienced three earthquakes within two weeks
The BGS said its provisional data suggested the earthquake originated at a depth of about 6.2 miles (10km).
Glenn Ford, a seismologist with the organisation, said the latest tremors in Leighton Buzzard were “an aftershock of the earthquake two weeks ago”, however, he said it was “an earthquake in its own right”.
“It’s not an unusual thing to be seen in the UK… this relieves the built-up stress in the rocks.”
The quake was “nothing to do with fracking or anything like that,” he said.
“It’s typical British tectonic activity that’s been going on for hundreds of years.”
Mr Ford said the UK experiences about 200 to 300 earthquakes each year, but 90% are “so minor that people can’t perceive them”.
He added: “If they felt this one in Japan, they wouldn’t even look up from their morning coffee.”
Why Leighton Buzzard?
Earthquake expert Dr Matthew Blackett, a reader in natural hazards at Coventry University, said the Leighton Buzzard tremors were likely caused by the fracturing of solid rock in “hidden fault lines”, several hundred metres below the surface.
“What seems to have happened is that this was an initial earthquake in a hidden fault – some stress or other has caused it.
“These two subsequent events are a readjustment of the fault lines to come back to some sort of stability.
“The crust has to adjust itself to become stable again, that seems to have happened to the poor people of Leighton Buzzard.
“It is quite possible that that sequence is now done, but it might be that there are still stresses there.
“If there are [further tremors], I think it will only be minor events.”