Did the earth move for you?

IT might be several weeks until St Valentine's Day, but a few people in north Suffolk have already felt the earth move.

But it wasn't being struck by Cupid's arrows that made them hear a big bang, nor being overcome by love that made them feel a little unsteady.

For those who had their feet firmly on the ground at around 5pm on Thursday afternoon felt an unexpected rumble and rattle.

At first it was a suspected earthquake, then it seemed it could be an explosion, next it appeared a jet breaking the speed of sound could be to blame, and finally a theory of military testing two counties away was put forward. But the true cause of the tremor remains a mystery.

One Suffolk resident, who did not want to be named, said he felt the tremor for about 10 seconds while just outside Halesworth.

“There was a loud rumble underneath and behind the building, and the whole place shook for several seconds,” he said.

“At my home near Stradbroke, I'm told there was a loud rumble and the shutter doors on the barn were shaking. Four others I asked in Stradbroke confirmed they had the same experience - one lady was relieved to hear others talking about it as she had been told she was imagining things, but she had been shocked at what happened.”

He said the experience was frightening but added: “It wasn't a sonic boom, or a heavy lorry nearby; we've all experienced those. This was different.”

He said a friend in Blythburgh said his boiler shook so much at the same time on Thursday that everything fell off the top. The Blythburgh resident at first thought it must be a sonic boom, but said it went on for too long.

After carrying out his own investigation on the web, the Stradbroke resident thought one possibility could be that it was linked to activity at the Ministry of Defence Shoeburyness test site, which has prompted people in Essex and Kent to complain of vibrations and shockwaves.

But a spokesman for the British Geological Survey, based in Edinburgh, which picked it up as a blip on one of its instruments in the region, said its cause lay in local activity.

He said: “We've had a couple of enquiries this morning from members of the public in a place called Saxmundham. They reported what they thought was an earthquake that lasted about three to four seconds. They said there was some rumbling and rattling but we checked our instruments in the area and the whole of East Anglia and there was not an earthquake.

“Our instruments 8km north of Saxmundham just showed it up as an event that was caused by something of an explosive nature. It definitely was not an earthquake and it was not felt throughout East Anglia. It was something very local.”

He suggested that road building or demolition work could hold the key to the mystery.

Meanwhile, a Suffolk police spokesman said they received a couple of calls from people in the Southwold and Halesworth areas, saying there had been a “big bang”.

But he confirmed there were no other calls received and there were no reports of untoward incidents.

On January 13, an earthquake measuring 1.5 Richter local magnitude was recorded by the British Geological Survey. It happened at 3.55am about 8km north-east of Bury St Edmunds and lasted 35.1 seconds.

Of the earthquakes felt in the UK, one was in Norwich on February 15, 1994, at 10.15am, measuring a magnitude of 4.0.

Generally, earthquakes measuring less than 3.5 on the Richter scale are not felt but recorded and it usually takes a magnitude of more than 5 to cause damage to buildings.