The British Geological Survey recorded
a Magnitude 2.4 Earthquake at a depth of about 11 km about 2 km to the southwest of the village of Lephinmore in Argyll and Bute, Scotland, at about 4.35 pm GMT on Tuesday 24 January 2017. This was not a major
event, and presented no
threat to human life or property, but was felt locally. This was followed by a second Earthquake with a Magnitude of 1.4 in approximately the same area slightly less than 24 hours later, which was also felt.
The approximate location of the 24 January 2017 Lephinmore Earthquake. Google Maps.
Earthquakes
become more common as you travel north and west in Great Britain, with
the west coast of Scotland being the most quake-prone part of the island
and the northwest of Wales being more prone to quakes than the rest of
Wales or most of England.
The
precise cause of Earthquakes in the UK can be hard to determine; the
country is not close to any obvious single cause of such activity such
as a plate margin, but is subject to tectonic pressures from several
different sources, with most quakes probably being the result of the
interplay between these forces.
Britain is being pushed to the east by the expansion of the Atlantic Ocean and to the north by the impact of Africa into Europe from the south. It is also affected by lesser areas of tectonic spreading beneath the North Sea, Rhine Valley and Bay of Biscay. Finally the country is subject to glacial rebound; until about 10 000 years ago much of the north of the country was covered by a thick layer of glacial ice (this is believed to have been thickest on the west coast of Scotland), pushing the rocks of the British lithosphere down into the underlying mantle. This ice is now gone, and the rocks are springing (slowly) back into their original position, causing the occasional Earthquake in the process.
(Top) Simplified diagram showing principle of glacial rebound. Wikipedia.
(Bottom) Map showing the rate of glacial rebound in various parts of
the UK. Note that some parts of England and Wales show negative values,
these areas are being pushed down slightly by uplift in Scotland, as the
entire landmass is quite rigid and acts a bit like a see-saw. Climate North East.
Witness
accounts of Earthquakes can help geologists to understand these events,
and the structures that cause them. If you felt the 24 January quake, or were in
the area but did not (which is also useful information) then you can
report it to the British Geological Survey here, or if you felt the 25 January or were in
the area but did not (which is also useful information) then you can
report it to the British Geological Survey here.
See also...
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