Earthquake: Brynmawr, Cardiff and valleys feel tremorson February 25, 2023 at 9:28 am

An earthquake has shaken parts of Wales overnight.

The British Geological Survey (BGS) said the 3.7 magnitude quake happened at 23:59 GMT on Friday. The epicentre was just north of Brynmawr, Blaenau Gwent, and west of Crickhowell, Powys.

BBC journalist Alex Humphreys said she felt the “mini earthquake” in Cardiff, 30 miles (50km) away.

Gwent Police said it had received “multiple calls” overnight but it was “business as usual” for the force.

The BGS said the earthquake was 1.8 miles (3km) under the Earth’s surface.

“My whole bed shook,” Ms Humphreys tweeted. Others described it as a “scary” experience.

The largest earthquake ever recorded in the UK was in the North Sea on 7 June 1931, with a magnitude of 6.1.

The epicentre was in the Dogger Bank area, 75 miles (120km) north-east of Great Yarmouth, Norfolk.

Wales’ most powerful quake was on the Llyn Peninsula, Gwynedd, in 1984 – measuring 5.4, it began at a depth of more than 12 miles (20km).

The BGS said smaller quakes were not unusual in Wales, with 70 measuring more than 3.5 between 1727 and 1984.

Listeners told BBC Radio Wales Breakfast that they felt the “earth shake” in Ebbw Vale, which brought people out of their homes and into the streets.

Robert Griffiths, from Rhiwbina, Cardiff, said he had just sat down to watch TV after a night out when “all of a sudden the whole house shook”.

“The ceiling creaked, we immediately turned the television off and thought ‘what on Earth was that?’

“It was kind of like 20 trucks had driven in front of the house so it was most unusual and quite strange.”

Elsewhere, Cat said she “thought we were going mad” in Blaenavon, Torfaen, as her “bed and house shook side to side”.

“My husband ran downstairs to see what was going on,” she said.

Dr Ian Stimpson, a senior geologist at Keele University, in Newcastle-under-Lyme, Staffordshire, said such events “happen relatively infrequently”.

“They are a big shock. An earthquake of this size, probably the UK has about three of them a year on average,” he said.