Japanese earthquake felt at the Cliffs

SHOCKWAVES from Wednesday’s 6.8 magnitude earthquake in Japan were detected in North Clare, due to a new scientific instrument at the Cliffs of Moher.
While people in the area would not have felt the earth move, the newly installed seismometer at the Cliffs recorded the event.
The state-of-the-art device, funded by the Geological Survey of Ireland (GSI) and part of the Outreach Programme for Seismology in Schools run by the Irish National Seismic Network (INSN), is the first of its kind to be installed in County Clare. The programme has 55 seismometers installed in schools countrywide.
Tom Blake, INSN director and experimental officer with the School of Cosmic Physics at the Dublin Institute for Advanced Studies (DIAS), said the seismometer is so sensitive it can easily pick up strong seismic activity on the other side of the world.
“The earthquake near the east coast of Honshu in Japan was clearly picked up by the Cliffs of Moher seismometer approximately 10 minutes after it struck at 9.08am local time. High atmospheric pressure over Western Europe, which resulted in a reduction background seismic noise, helped to provide a very clear reading,” he explained.
“Our earth is more elastic than one might think. An earthquake has the same effect on the earth as a pebble does when dropped into a pool. The ripple effect of other recent earthquakes in Negros (The Philippines) and Siberia (Russia) was felt in North Clare when the energy or shockwave from the quakes travelled under the Cliffs of Moher and were subsequently registered by the seismometer,” he continued.
Speaking to The Clare Champion, Mr Blake said that while the instrument can pick up seismic events around the world, Ireland is “never going to have an onland earthquake of a magnitude that causes severe structural damage like we see in other part of Europe. The strongest event that people experienced on the east coast of Ireland was when a 5.4 magnitude earthquake occurred off the coast of Wales in July 1984.”
“The instrument at the Cliffs is capable of picking up earthquakes on the other side of the world. We pick up events that occur on the Mid-Atlantic Ridge, about 1,800km away. Another of those happened on Wednesday morning. It was 4.8 magnitude on the Richter scale so our instruments respond to all these events,” he added. 
Mr Blake said the Cliffs of Moher seismometer also records small earth tremors that occasionally occur around Ireland, the most recent of which was felt in north Donegal on Tuesday night. The 1.1 magnitude tremor struck at a depth of 3km at 9.23pm in the Buncrana and Milford regions.
A 2.7 magnitude tremor two years ago in Lisdoonvarna remains the strongest onshore earthquake recorded in Ireland since records began in 1978.
“Although Ireland does not sit on any major plate margin, it is still susceptible to earthquakes as we saw in Donegal this year and in Clare in May 2010. The new seismometer would certainly have been well placed to register and record the North Clare earthquake. This was a very important seismic event as it was the first time that a tremor had occurred in the west of Ireland since records began,” commented Mr Blake.
While it may feel like there are more earthquakes in Ireland than ever before, this is not the case.
“The reason there seems to be more earthquakes occurring is simply because there is more reporting of earthquakes. We don’t see much difference year-on-year in the number of events occurring but with people using mobile phones and good cameras, information gets recorded and sent around the world very quickly. The influence of media and social media makes it feel like there are more,” Mr Blake explained.
The Burren and Cliffs of Moher Geopark is the latest Geopark to operate a seismometer. Mr Blake noted the success to date of the seismometer at the Cliffs since its installation during February could become the catalyst for the formation of a Geopark seismic network.
“Already, we have seen seismometers installed at the Marble Arch Caves Geopark in County Fermanagh, the Copper Coast Geopark in Waterford and now the Burren and Cliffs of Moher Geopark. I would like to see a similar type instrument fitted out at every Geopark in Europe. Our understanding of earthquakes would be greatly improved by the development of such an expansive network,” stated Mr Blake.
The new seismometer is on public display at the Cliffs Exhibition at the Cliffs of Moher Visitor Experience.
According to Cliffs director and Clare Tourism Forum member, Katherine Webster, “Visitors to the exhibition at the Cliffs can see the seismometer in action. It is so sensitive, it can pick up actions such as a person jumping up and down, although these readings do show up differently from an earthquake.”

“Although Ireland does not sit on any major plate margin, it is still susceptible to earthquakes, as we saw in Donegal this year and in Clare in May 2010. The new seismometer would certainly have been well placed to register and record the North Clare earthquake. This was a very important seismic event as it was the first time that a tremor had occurred in the west of Ireland since records began,” commented Mr Blake.
While it may feel like there are more earthquakes in Ireland than ever before, this is not the case.
“The reason there seems to be more earthquakes occurring is simply because there is more reporting of earthquakes. We don’t see much difference year-on-year in the number of events occurring but with people using mobile phones and good cameras, information gets recorded and sent around the world very quickly. The influence of media and social media makes it feel like there are more,” Mr Blake explained.
The Burren and Cliffs of Moher Geopark is the latest geopark to operate a seismometer. Mr Blake noted the success to date of the seismometer at the Cliffs since its installation during February could become the catalyst for the formation of a geopark seismic network.
“Already, we have seen seismometers installed at the Marble Arch Caves Geopark in County Fermanagh, the Copper Coast Geopark in Waterford and now the Burren and Cliffs of Moher Geopark. I would like to see a similar type instrument fitted out at every geopark in Europe. Our understanding of earthquakes would be greatly improved by the development of such an expansive network,” stated Mr Blake.
The new seismometer is on public display at the Atlantic Edge Exhibition at the Cliffs of Moher Visitor Experience.
According to Cliffs director and Clare Tourism Forum member, Katherine Webster, “Visitors to the exhibition at the Cliffs can see the seismometer in action. It is so sensitive, it can pick up actions such as a person jumping up and down, although these readings do show up differently from an earthquake.”