The British Geological Survey (BGS) has revealed that a small earthquake has been recorded about 150 miles east of Aberdeen.
BGS said the 3.6 magnitude quake happened at about 14:30 on Monday, and was the third to be recorded in the area since 2019.
BGS said the 2019 quake was felt by workers in the Elgin-Franklin oil field.
It is not yet clear whether yesterday's tremor was felt by offshore workers.
'Seismic region'
The United Kingdom Continental Shelf, waters surrounding the UK and including the North Sea, is rated as a "low to moderate seismic region".
A 6.1 magnitude earthquake was recorded in the Dogger Bank area of the North Sea in 1931.
BGS said: "This earthquake is located close to (within 10km) of both the magnitude 3.1ML Central North Sea event which occurred on 14 February 2021 & the magnitude 4.2 ML Central North Sea event which occurred on 24 September 2019.
"The 4.2 ML event was reported felt by several people on the Production/Utilities/Quarters (PUQ) platform in the Elgin-Franklin gas and oil field."
Rare event
Earthquakes in Scotland are most often attributed to glacial rebound.
Until about 10,500 years ago much of the north of the UK was covered by a thick layer of ice – which pushed the rocks down into the underlying mantle.
These rocks have been slowly rising back up ever since the ice melted, causing occasional earthquakes in the process.
The UK is also subject to tectonic stresses caused by the expansion of the Atlantic Ocean, which is slowly pushing the entire mass of Eurasia to the east, and from the northward motion of Africa, which is pushing into Europe from the south.