Should northern England worry about quakes?

From Reuters: 

Two earth tremors in as many weeks might be enough to stir fears among northerners that something ominous is going on beneath their feet.

But seismologists' message to anybody who might be worried about the possibility of "the big one" north of the Wash is simple: "don't panic."

The British Geological Survey (BGS) recorded a 3.6-magnitude tremor in North Yorkshire at 9 p.m. on Monday. It followed another nearby quake of the same magnitude on December 21.

"It is significant by UK standards but nothing to worry about, absolutely nothing to worry about. You don't get damage until magnitudes 5s and they are very rare in the UK," said Julian Bukits, a seismologist at the BGS.

"It's not until you get up to 4.5-5s that you will even get a cracked ceiling, a hairline crack, or a tile falling off a roof."

Smaller earthquakes are less worrisome still, he added.

"Imagine sitting in your office and a heavy lorry going past and maybe your coffee cup, an empty coffee cup I should say, rattling on your desk or maybe your monitor shaking for a few seconds -- that's as much as you're going to feel from a 3.6."

The largest tremor in Britain was the 1931 Dogger Bank earthquake, which measured 6.1 on the Richter scale and was felt in France and Belgium.

The two earthquakes in north England are in line with the average frequency of tremors of that size in Britain, which occur about once a year.

"There is nothing particularly unusual about the occurrence of the two small earthquakes in northern England," said Robert Holdsworth, a geology professor at Durham University.

Worldwide there are 14,500 quakes of 3.6 magnitude a year, Bukits said.

"Other countries that have real earthquakes -- Japan and USA and places like that -- probably laugh at the media hysteria that we create for a 3.6," he added.

(Reporting by Olesya Dmitracova; Editing by Steve Addison)