The earth moved for many people in and around the Bradford district last week, in what seemed like a freak earthquake, but according to seismologists, tremors are a frequent occurrence in the UK.

Often they are so slight we don’t feel them. The 3.6-magnitude quake which struck 9km north-west of Ripon just after 9pm last Monday – which experts claim was the largest quake in the area for more than 40 years – was significant enough for many people around the district to feel the ripple effect. Residents in Skipton, Ilkley, Baildon, Bingley, Rawdon, Yeadon and Calverley spoke of windows, doors and sofas shaking.

It even shook the walls of a castle dating back to the 15th century. Sir Thomas Ingilby, owner of Ripley Castle, near Harrogate, wasn’t sure it was a tremor until he logged on to Facebook.

“We were on the first floor of the castle in our flat and there was a roaring noise followed by a loud bang, like a large piece of furniture falling from a height,” says Sir Thomas. “The whole place shook and chandeliers jingled. My reaction was to open windows and see if we had lost a chimney.”

Sir Thomas says it was the recent earthquake in Cumbria that prompted him to consider it could be a tremor.

While we don’t suffer earthquakes on the scale of some countries, quakes are part of the UK’s long geological history and are related to the movement of the mid-Atlantic plate.

Expert Brian Baptie, who studies earthquakes for the British Geological Society, says quakes the size of last Monday’s happen about once a year in this country. He would expect such a quake to be widely felt, possibly up to 100km away.

“People may feel doors and windows rattle or objects moving on shelves and pictures shaking. All those things are what you would expect,” he says.

While some may blame freak weather caused by global warming – December was the coldest on record in Britain – seismologists say the weather has no bearing on quake activity, and we’re not likely to see an increase.

Mr Baptie says small quakes occur every 12 to 18 months but are more likely to appear in another part of the country rather than in the same area again.

“There is no evidence to suggest they are increasing because of global warming or because of bad weather. We have always had them in Britain – it is just they’re smaller than those you get in other places,” he says.

With earthquakes happening due to faults in the earth put down to our geological past, he says some quakes “are activated by present-day stresses which this part of the world is experiencing.”

The reasons for earthquakes in the UK are unclear, but include regional compression caused by motion of the Earth’s tectonic plates, and uplift resulting from the melting of ice sheets that covered parts of Britain thousands of years ago.

Dr Roger Clark, senior lecturer in geophysics at Leeds University, says: “One of the reasons we have earthquakes in this country is that the whole earth’s crust is still rising back up after all the thick ice sheets in the last Ice Age – glacial rebound is the posh name for it.”

Dr Clark says that while Britain isn’t on the boundary of the earth’s tectonic plates, it is right in the middle. “And we feel the stresses,” he adds.

The largest British earthquake, with a magnitude of 6.1 ML, occurred in 1931 in the North Sea and caused a reasonable amount of damage.

It was felt in Britain as well as Ireland, Holland, Belgium, Northern France, parts of Germany, Denmark and Norway. Damage in Britain was reported from 71 different places, with the strongest effects felt in Filey, on the North Yorkshire coast.

In February 2008, an earthquake measuring 5.2 on the Richter Scale in Lincolnshire caused superficial damage to chimney pots in the epicentral area, and was widely felt across the country, including parts of the Bradford district.

According to the British Geological Society, earthquakes of such magnitude occur on the UK mainland approximately every 30 years, but are more common in offshore areas.

On December 21 last year, a week before the Ripon earthquake, a quake measuring 3.5 on the Richter Scale struck in Coniston in the Lake District. And as far back as 1780, quakes have been recorded in our region. The two largest occurred in Wensleydale in 1780 and Skipton in 1900.