A second earthquake has hit Scotland's Highlands within a week.
The latest quake - measuring 2.2 magnitude - struck just outside Roybridge, near Spean Bridge, at 9.29pm on Friday night.
The depth was recorded by the British Geological Survey (BGS) at 7.5km (4.7 miles).
A spokesman for the organisation tweeted: "A small number of reports have been received by members of the public in the Roybridge area indicating they felt this event."
The earthquake was described by Glenn Ford, the BGS seismic analyst on call at the time of the tremor, as "absolutely tiny" when compared with other quakes seen around the world.
"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," he said.
"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 and felt the tremor, said: "It was about 9.30pm and I felt the tremor, but I heard it much more. It was really quite loud, like a train rumbling past the house.
"To me it seemed like a train rumbling past. I knew what it was straight away, I have heard it before and felt the tremor before."
The tremor was 17 billion times smaller than the earthquake that devastated Japan in 2011, Mr Ford said, adding: "You literally wouldn't look up from your coffee or your newspaper for an earthquake that size in California or Japan."
He said there were a number of factors as to why people felt earthquakes in the UK, including size and depth.
"The other type is time of day. Because people are not used to earthquakes in the UK, they put a small earthquake, because it could just be a small tremor, down to traffic noise, so if somebody is in a very remote area like this which occurred last night there is much better opportunity to actually feel it because they are nice and still, it was late at night, and probably in a sedentary position," Mr Ford said.
"Normally if the roads had been busy or you're near a motorway, you'd just put it down to traffic."
Earlier this week, a 3.1-magnitude earthquake hit the nation just before 2am on Tuesday.
The epicentre was 88 miles northwest of Glasgow, near the town of Lochgilphead.
The US Geological Survey was sent more than 40 reports from people saying they had felt the ground move - and the reports came from as far apart as Edinburgh and Ballycastle in Northern Ireland.
That tremor was 10km below the Earth's surface.
BGS data shows the UK experiences up to 300 earthquakes each year.
Tremors measuring between 3.0 and 3.9 magnitude happen on the mainland around once every three years.