Blacksod Lighthouse - one of the nearest points on the mainland to the quake epicentreTHE magnitude 4 earthquake some 80 to 90 kilometres off Co. Mayo on Wednesday morning last caused widespread alarm but only minor structural damage along the western seaboard.

Deep rumbling sounds like of that of an oncoming train or a passing articulated lorry were reported in a number of areas in counties Mayo and Sligo and there were hairline and even wider cracks visible in some buildings afterwards.

One alarmed couple, Phil and John O’Hara, who live in Aclare, near the Sligo/Mayo border, had a chunk of masonry knocked off the chimney of their bungalow.

Mrs. Phil O’Hara, who lives with her husband, John, in the townland of Killure, Aclare, said: “I was walking down the hallway just before 9 a.m. when I heard the bang. It was like a drum or a rap of thunder.

“After breakfast I found a three pound lump of concrete on the ground when I went out to hang some clothes on the line. It had fallen from the chimney. I was quite frightened to be honest with you.”

Mrs. O’Hara’s call was only one of hundreds that Midwest Radio took in the hour or so after the tremor, the first recorded off Mayo since instrumental seismic readings began in the area.

One man living in Crossmolina reported ‘my whole house shook’ while a fisherman attaching an engine to a boat at nearby Lough Conn said the waters of the lake had become briefly agitated.

“One second the lake was flat calm,” the angler explained. “The next, the boat was bobbing up and down as if some invisible hand was rocking it.”

A further caller to the radio from the north Mayo area said she was awakened just before 9 a.m. by the bed actually shaking.

The young female added: “I felt the bed actually moving. I thought it was my dad outside with machinery. But when I got up there was no sign of dad around. He was over in the bog at the turf. The sound and movement was enough to wake me from my sleep. It was really scary.”

A resident of Achill Island, Peadar McHugh from Bunnacurry said he was getting up when he heard a rumbling noise coming from the north of the island ‘like an articulated truck approaching’.

“The noise came up through the house,” he explained. “The ceiling creaked. It lasted about two or three seconds. Then it was all over.”

The tremor was described as ‘surprisingly large’ by Brian McConnell of the Geological Survey of Ireland.

It had occurred 80 to 90 kilometres west of Belmullet about three to four kilometres beneath the seabed, ‘quite shallow’ for an earthquake.

There had been no quake off Co. Mayo since records began, Mr. McConnell stated.

He emphasised, however, there was a known fault line in this area so there was a ‘good geological reason’ for the quake happening.

Mr. McConnell ruled out the possibility of the tremor having anything to do with oil and gas exploration activity off the western seaboard.

However, a Sinn Fein member of Mayo County Council has called for ‘a detailed and comprehensive investigation’ into the earthquake.

Erris based Councillor Rose Conway-Walsh said there was public concern that the tremor was in some way linked to the works being carried out on the Corrib Gas project.

“People need to be assured that the seismic testing that is being done along the sea bed off the west coast is not in any way connected to the earthquake,” Councillor Conway stated.

She added: “Another concern people have is that the prospect of an earthquake has not been covered in the environmental impact statement and what happens if the piping infrastructure of the terminal is damaged by an earthquake.

“They also want to know if any of the existing Corrib infrastructure has moved or been damaged by this morning’s earthquake.

“All these critical issues need to be addressed in a timely, transparent and accurate way by Minister Rabbitte, the developer and the various departments and bodies that have been tasked with responsibility for monitoring the project.”