Aftershocks from the earthquake which shook parts of Galway county and Mayo early yesterday could occur in the new few days, but these are not expected to be anything of significance, a geological expert said last evening.
The quake, which measured 4.0 on the Richter Scale, took place just after 9.30 yesterday morning in an area roughly 40 miles off the Mayo coast. The effects were felt right across county Mayo and in north Connemara and in some areas along the Galway coast.
There were also unconfirmed reports of the rumbles being felt in some areas of Galway city, with reports of dishes shaking in kitchens.
The tremors were felt all along the Mayo coast, from Blacksod down towards Inis Boffin, with members of the public there reporting furniture and dishes shaking for a few seconds. It was felt significantly as far inland as Lough Conn.
It was detected by the British Geological Survey which monitors quake happenings and which described it as ‘a rare and unusual event.’ Every year about 200 small earthquakes happen around Ireland.
The BGS reported that an earthquake with a magnitude of 4 and a depth of 3km occurred of the west coast of Ireland at 8.58am. According to its Historical Earthquake Database, this is the first earthquake to occur off the Mayo coast in over 40 years, as well as the largest to have occurred off the Irish coast in a number of years.
Earthquakes measuring 4 on the Richter Scale are described as light with ‘noticeable shaking of indoor items, rattling noises’, but significant damage is unlikely.
People who felt the earthquake described dishes shaking in cupboards and a sensation that felt like a plane flying low over a house or a heavy truck passing by their home.
NUI Galway lecturer in Geography, Dr Kieran Hickey who is well versed in seismic activity said that this quake was significantly larger than the average earthquake felt in this country.
“The earthquake was 60 kilometres off the northern tip of Mayo, at magnitude 4, which is quite high by Irish standards. We have had earthquakes in the past but they are normally in the 1 or 2 magnitude category,” he said last evening.
"It is a rare and unusual event. We don't have a recent track record of such events, but there was an earthquake that took place in Clare in 2010 that was magnitude 2.2
“People would have felt this earthquake on the coastal area but less the further inland you go.”
He went on to say that it is difficult to assess whether there will be tremors or aftershocks in the coming days, because of the quake, but that if there were any, they would not be anything significant or worthy of causing concern.
Tom Blake, director of the Irish National Seismic Network, said the region had never experienced an earthquake of this size before.
The largest earthquake recorded in Ireland occurred in 1984 when a magnitude 5.4 quake struck off the coast of Wales causing tremors and structural damage along the east coast.
Mr Blake said there were some reports of minor structural damage this morning but this has yet to be confirmed.
