A minor earthquake hit Donegal on Tuesday, for the second time in six weeks.
Several residents reported disturbances before midnight in the Buncrana and Milford region of North Donegal. The tremor was picked up at the British Geological Survey.
"We've recorded an earthquake with a magnitude of 1.1," said BGS spokesman David Galloway.
"In terms of earthquakes, it is quite a small earthquake, but it was only at a depth of three kilometres hence probably why people felt it and the fact that it was quite late at night, when there was not a lot of traffic noise."
On January 26 an earthquake in the county registered 2.2 on the Richter scale at Buncrana.
"It happens naturally in the north of Ireland but not as often, say, as northern Scotland or the south of Wales," Julian Bukits, assistant seismologist with the BGS told the BBC when it occurred.
"No one can really explain it for Ireland, it's just a geological phenomenon. Usually, with reports of this kind, people think it's a heavy lorry going past their home."