WHEN you think of Britain, the first word that springs to mind probably isn’t “volcano” – but our tiny nation is littered with the things.
There are dozens of long-extinct volcanoes across the United Kingdom, including one just 80 miles from London.
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Thankfully none of them are active so we’re not at risk of suffering a painful lava death.
British volcanoes haven’t been active since around 50 million years ago.
So that’s why you can safely walk over them, and there’s a good chance that you might have already. Take a look at our interactive map plotting them out:
For Londoners, your closest bet is at Warboys, which is just 80 miles away in Cambridgeshire.
Around 600 feet below ground are rocks believed to be the remnants of a volcano dating back around 300 million years.
Now Warboys is a peaceful village with just over 4,000 residents – but it was once a hotbed of volcanic activity.
Some of Britain’s best hikes are also on top of long-extinct volcanoes.
For instance, the Lake District’s Helvellyn is made from volcanic rocks that were created in the caldera of an ancient volcano.
These explosive eruptions would’ve happened around 450 million years ago.
It’s the same story for the Scafells (including Scafell Pike, England’s highest peak), which is the remains of a volcanic eruption dating back 400 million years.
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Another volcano turned tourist hotspot is Glen Coe up in Scotland.
It’s a stunning glacial glen that cuts right through the rocks of the Scottish Highlands.
And you guessed it: the rocks at Glen Coe are volcanic in origin.
In fact, they’re the remains of an ancient supervolcano that erupted around 420 million years ago.
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A supervolcano needs to have had an eruption of level 8 on the volcanic explosivity index – the highest value.
One of the more remote entries on the list is Rockall, a small granite islet in the North Atlantic Ocean. It’s 187 miles west of Soay in Scotland.
It’s claimed by the United Kingdom (although this is disputed by Ireland), and is considered uninhabitable – and is believed to be the result of volcanic activity long ago.
Another great edge-of-Britain volcano is up in Esha Ness on Shetland’s Mainland.
HOW DO VOLCANOES ERUPT?
Here’s what you need to know…
Volcanoes are formed when a hot liquid-like substance called magma breaks through the Earth’s crust.
Once the magma reaches the surface and gushes onto the Earth’s surface or into the atmosphere, this is known as a volcanic eruption.
Volcanic eruptions can release lava, rocks, dust, volcanic ash, and toxic gases into the atmosphere.
Some eruptions and huge and very deadly – but others can result in very small flows of lava that are easily avoided.
Volcanoes normally give off warning signs before an eruption, which might include tremors, or the release of gases.
This can give people nearby time to evacuate.
Picture Credit: Getty – Contributor
It’s a rocky peninsula made of the remains of a stratovolcano that was active around 395 million years ago.
A stratovolcano is the sort of fun conical volcano that you imagine when you hear the word volcano – like Italy’s Mount Etna, or Mount Doom from The Lord of the Rings.
It’s built up of lots of layers of material and lava, and usually has a summit crater.
The Esha Ness stratovolcano is believed to have had violent and explosive eruptions, helping to create what is now a beautiful and rugged landscape.
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One of Northern Ireland‘s best-recognised tourist attractions is also volcanic: the Giant’s Causeway.
This massive collection of basalt columns is linked to a volcanic fissure eruption.
That’s when a fissure in the Earth’s crust lets the contents of a subsurface magma chamber out – with explosive results.
In this case, it’s believed that molten basalt popped up through chalk beds to create a volcanic plateau around 50 to 60 million years ago.
What is a supervolcano?
Here’s what you need to know…
- A supervolcano is a large and highly explosive volcano
- It needs to have had an eruption with a Volcanic Explosivity Index of 8 – the highest recorded value
- This means it will have deposited more than 240 cubic miles of material during eruption
- They occur when magma rises into the crust but can’t break through, creating immense pressure and a large magma pool
- Eventually the crust is unable to contain this pressure, causing an eruption
- There have been at least 60 supervolcano-grade eruptions, but many more may have occurred that have yet to be discovered
- The biggest of these known eruptions was Wah Wah Springs in Utah, USA, which ejected up to 5,900 cubic km of material 30.6million years ago.
As this lava cooled and contracted, it’s believed to have fractured like drying mud – leaving us with the iconic pillars that we know and love today.
Thankfully that volcanic activity has died down, so you can stroll around the area without fear of sticking your foot in a surprise lava pool. Phew.
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