Scotland has been hit by its second earthquake in less than a week, in a tremor that a seismologist described as “quite unusual” because people could actually feel it. The British Geological Survey (BGS) recorded a 2.2 magnitude earthquake just outside Roybridge, near Spean Bridge, in the Highlands, shortly before 9.30pm on Friday. Glenn Ford, the BGS seismologist on call at the time of the tremor, described the earthquake as “absolutely tiny” when compared with others registered around the world. The earthquake had a depth of 7.5km. The night-time tremor was 17 billion times smaller than the earthquake that caused devastation in Japan in 2011, Ford said, adding: “You literally wouldn’t look up from your coffee or your newspaper for an earthquake that size in California or Japan. “In UK terms, because we are a very low seismic area, we only perhaps get about 15 earthquakes a year of this size or greater, so it’s quite unusual in that respect. “We get about two to three hundred earthquakes every year somewhere in the United Kingdom area, so the fact that this one was actually felt was unusual because approximately 90% of them are so small nobody actually perceives them.” Iain MacDonald, who was staying in the village at the time of the earthquake, was among the people who noticed it. “It was about 9.30pm and I felt the tremor, but I heard it much more,” he told PA Media. “It was really quite loud, like a train rumbling past the house. I knew what it was straight away; I have heard it before and felt the tremor before.” Village resident Michael Sillars also likened the tremor to a passing train and said he “heard a big rumble and the house shook”. Ford said people might have felt Friday’s earthquake because of where it occurred and the time of day. “Because people are not used to earthquakes in the UK, they put a small earthquake … down to traffic noise, so if somebody is in a very remote area like this … there is a much better opportunity to actually feel it because they are nice and still – it was late at night – and probably in a sedentary position,” Ford said. “Normally, if the roads had been busy or you were near a motorway, you’d just put it down to traffic.” A 3.1 magnitude earthquake was reported by the United States Geological Survey (USGS) on Tuesday just before 2am, with its epicentre about 11 miles (18km) north-west of the town of Lochgilphead, near the west coast of Scotland. More than 30 people told the USGS that they had felt the tremor, with reports coming from as far as Edinburgh, and Ballycastle in Northern Ireland. Rosemary Neagle, who lives on a farm in Kilmartin Glen, near Lochgilphead, said after Tuesday’s quake she initially thought something had exploded in one of her sheds. She told BBC Radio’s Good Morning Scotland programme: “It kept on intensifying and the house vibrated. It rumbled on for about 10 seconds afterwards, so it was quite frightening. “I have experienced them before here but never to that extent. The house has never shook like that in the past.” Tuesday’s earthquake happened 10km below the Earth’s surface, the agency said.