- 3.7 magnitude earthquake hits Jersey
- Read Islanders tweets about the quake
- Maps of the exact location the quake hit
- The history of earthquakes in Jersey
No damage was reported but within seconds of the quake striking at 10.55 pm thousands of Islanders took to social media to say they had felt the earth move.
Many also reported hearing a loud noise at the same time as the earthquake, which experts say was likely to be down to buildings being moved by the vibrations spreading out from the epicentre.
- 1926/7 – On 30 July 1926, a relatively large earthquake was measured in the Channel, with Islanders reporting feeling the quake. The 5.5-magnitude quake, which hit shortly after lunchtime, was the largest the Island has seen. Just seven months later, in February 1927, the Island suffered another earthquake measuring over five on the Richter scale, this time measuring 5.4. Although relatively large for the UK, the quakes were measured deep underground and there were no lasting consequences from the tremors.
- 1990 – On 30 April 1990 a 3.5-magnitude earthquake started just south of St Aubins Bay and was felt throughout the Island. As well as a number of reports in Jersey, the quake was powerful enough to be felt in Guernsey, although at a much lower intensity. People reported houses shaking and heavy objects falling, although no structural damage occurred.
- 2002 – A high-intensity quake was measured on 19 November 2002. Although smaller than the quake of 1990, the 2.5-magnitude quake combined with its locality meant that residents throughout the Island felt the tremors. The quake lasted nearly a minute and is at present the largest 21st century earthquake measured in Jersey.
- 2013 An earthquake hit Jersey on Boxing Day, which measured 1.8 on the Richter Scale.
- 2014 There was a huge spike in the number of earthquakes to have hit Jersey with eight quakes hitting the Island or its water in the space of eight days during July. The first was a 4.2 magnitude quake – the largest seen in the Channel Islands for nearly 90 years and the 35th largest ever recorded across the British Isles. Jersey Met described the large number of earthquakes as very unusual, though many were too small to be felt by Islanders.
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John Searson, senior forecaster at the Jersey Met Office said the quake, which was also felt in Guernsey, had been fairly large for the Channel Islands.
‘It was 2.9 on the Richter scale, that is fairly large for this part of the world and certainly big enough for most Islanders to have felt it if they were in the right place,’ he said. ‘The noise people heard is probably related to where you are.
‘For instance if you are in a house and the house starts moving the noise is likely to be down to the movement of the building.’
The epicentre was around 6 km south-west of Corbière and it was the largest tremor to be felt in Jersey since 12 July last year, when a 4.5 magnitude quake struck. That was the biggest earthquake to have hit Jersey in 90 years and the 35th largest ever recorded in the British Isles.
Despite being smaller in magnitude, last night’s earthquake was measured at level three intensity – the same as the 2014 quake.
Islanders from St Ouen to Grouville reported feeling the tremor. Writing on the JEP’s Facebook page Carolyn Connor said: ‘In St Saviour’s Road, laying in my bed and the doors rattled and you could feel the movement in the walls and floor.’
Judy Beaumont also felt it. She said: ‘Sat watching telly in the lounge at flats in First Tower. Everything started to shake and rattled the ornaments which chinked together on the shelf. The rumble was very deep.’
Angela Rosamond added: ‘In bed trying to sleep and my bed appeared to leave the floor momentarily and the walls moved.’
However there were those who did not feel the earthquake, including Alison Yates and Lee Mack who said they had not felt a thing in St Clement and James McCloskey who said: ‘I was on St Aubin’s beach walking the dog before bed, didn’t feel or hear a thing!’
The British Geological Survey also wants to hear from Islanders who felt the earthquake.
You can record your experience, which will be used for research purposes, here
Compared with much of the UK, Jersey is a hive of earthquake activity, although the vast majority of ‘quakes measured in the Island are so small they are not felt by Islanders.
Tony Pallot, principal meteorological officer at the Met Office, said that most do not start in the Island, but rather in the Channel.
‘The most favoured spot for earthquakes over here is probably halfway between here and France,’ he said. ‘Most of what causes them is just settlement of the underlying rocks around this area.’
This settlement causes underground movement which, at a high enough magnitude, causes tremors that can be felt above ground.
Mr Pallot added: ‘It depends where the ‘quake is as to whether or not it is felt. If it’s a local one, somewhere around the Island, then it probably needs to be at least 1.5 magnitude for people to be able to feel it.
‘There was quite a big one a few years ago in Brittany which was a magnitude of around four, which was felt over here. Obviously, the further away the bigger they have to be for us to actually feel them.’
As well as the magnitude, there are a number of contributory factors as to whether or not a ‘quake is felt.
‘There are lots of different issues to factor in – where it started, depth, what you are doing at the time,’ said Mr Pallot. ‘It can depend on the rock structure on which you are standing because the way the seismic wave behaves may be different depending on what sort of structures you are on, whether it’s sand or soil or something that is directly connected to the bedrock.
‘And because of the low intensity of earthquakes over here, it depends where you are. If you have a lot of distractions around you, you probably won’t notice it, but if you’re somewhere quiet you’re more likely to.’
In terms of measurements on the Richter scale, the tremors recorded in Jersey are comparatively small in earthquake terms, and there are very few accounts of measurements over three. ‘All of the earthquakes we get over here are very small,’ said Mr Pallot. ‘Your big earthquakes – magnitudes of six, seven and eight – all occur on plate boundaries, and the nearest plate boundary to here is probably the mid-Atlantic ridge.’
The largest ‘quakes ever recorded in the Channel Islands date back as far as the 1920s, when in consecutive years the Island was hit by two ‘quakes with magnitudes over five, two of the largest recorded in the British Isles.
The Equipment
IT was the two earthquakes in the 1920s that prompted the introduction of a seismometer to the Island at the Maison St Louis Observatory by the Jesuit priest Father Père Charles Rey, who recorded and forecasted the daily weather.
After using the original seismometer for decades, the Met Office installed new modern equipment in 1981 in conjuncture with the British Geological Survey and Jersey Water.
Following reports of activity around Val de la Mare, Jersey Water was interested in seeing the level of activity around the reservoir. At the same time, the BGS was introducing seismometers across the UK to measure activity throughout the British Isles.
Mr Pallot added: ‘The British Geological Survey was keen to set up at least one seismometer in the Channel Islands, and we were keen to replace our ageing seismometer with something a bit more modern.
‘We ended up with a three-party arrangement, and the British Geological Survey installed four seismometer sets, one under the tunnels at St Aubin, one not far from the dam at Val de la Mare, one up at Les Platons and a complete three-station set at Maison St Louis.’
The three-station set at the observatory measures along three planes – the vertical, east-to-west and north-to-south directions – as opposed to the other three seismometers, which measure only on the vertical plane.
Mr Pallot said: ‘They work by having a coil sitting on a couple of very light hairsprings in a magnetic field. As the coil moves up and down it will generate an electrical signal.
‘This gives us a nice little micro-network which allows the BGS to analyse any microseismic activity in and around the Channel Islands.’
The equipment has remained the same since 1981, although the way in which the movement is recorded has improved dramatically, with the BGS now able to receive electronic signals in real time. ‘If something happens, they probably know about it before we do,’ said Mr Pallot. ‘As you saw with the Boxing Day ‘quake, by the afternoon we knew where it was, we knew what magnitude it was and all the other information. That’s the difference 20 years has made in getting data back.’
Angela Rosamond: In bed trying to sleep and my bed appeared to leave the floor momentarily and the walls moved.
Melanie Luce: Thought a loud motorbike had started up outside at first. Had to turn the television off to work out what the noise was!
James Mc Closkey: I was on St Aubins beach walking the dog before bed, didn’t feel or hear a thing!
Sharon Le Bredonchel: In my lounge watching TV in St Helier. Very deep rumble and lounge shook and doors.
Magda Bla: Had a bath and thought it had turned into Jacuzzi!
Lee Mack: In St Clement, did not hear or feel a thing!
Judy Beaumont: Sat watching telly in the lounge at flats in First Tower. Everything started to shake and rattled the ornaments which chinked together on the shelf. The rumble was very deep and went on for minutes.
Carolyn Connor: In St Saviour’s Road, laying in my bed and the doors rattled and you could feel the movement in the walls and floor.
