Risk of supervolcano eruption big enough to 'affect the world' far greater than thought, scientists say

Scientists have analysed the molten rock within the dormant supervolcano beneath Yellowstone National Park and found that eruption is possible without any external trigger

The eruption of a “supervolcano” hundreds of times more powerful than conventional volcanoes – with the potential to wipe out civilisation as we know it – is more likely than previously thought, a study has found.

An analysis of the molten rock within the dormant supervolcano beneath Yellowstone National Park in the United States has revealed that an eruption is possible without any external trigger, scientists said.

Scientists previously believed many supervolcanic eruptions needed earthquakes to break open the Earth’s crust so magma could escape. But new research suggests that this can happen as a result of the build-up of pressure.

Supervolcanoes represent the second most globally cataclysmic event – next to an asteroid strike – and they have been responsible in the past for mass extinctions, long-term changes to the climate and shorter-term “volcanic winters” caused  by volcanic ash cutting out the sunlight.

The last known supervolcanic eruption was believed to have occurred about 70,000 years ago at the site today of Lake Toba in Sumatra, Indonesia. It caused a volcanic winter that blocked out the sun for between six to eight years, and resulted in a period of global cooling lasting a thousand years.

A supervolcano under Yellowstone Park in Wyoming last erupted about 600,000 years ago, sending more than 1,000 cubic kilometres of ash and lava into the atmosphere – about 100 times more than the Mount Pinatubo eruption in the Philippines in 1982, which caused a noticeable period of global cooling.

 

Following Pinatubo’s eruption, the global average temperature fell by about 0.4C for several months. Scientists predict that a supervolcanic eruption would cause average global temperatures to fall by about 10C for a decade – changing life on earth.

Scientists have analysed magma from the Yellowstone caldera, a 55-mile-wide underground cavern containing between 200 and 600 cubic kilometres of molten rock, to see how it responds to changes in pressure and temperature.

Using a powerful X-ray source at the European Synchrotron Radiation Facility in Grenoble, France, the researchers found that the density of the magma decreased significantly at the high temperatures and pressures experienced underground.

Density variations between magma and the rock surrounding it means that the lava within the supervolcano’s caldera can produce big enough forces to break through the earth’s crust, allowing the molten rock and ash to erupt from the surface, the scientists said.

“The difference in density between the molten magma in the caldera and the surrounding rock is big enough to drive the magma from the chamber to the surface,” said Jean-Philippe Perrillat of the National Centre for Scientific Research in Grenoble.

“The effect is like the extra buoyancy of a football when it is filled with air underwater, which forces it to the surface because of the denser water around it,” Dr Perrillat said.

“If the volume of magma is big enough, it should come to the surface and explode like a champagne bottle being uncorked.”

The study, published in the journal Nature Geoscience, was possible because the X-ray machine at Grenoble was able to take accurate density measurements at temperatures of up to 1,700C and pressures 36,000 times greater than normal atmospheric pressure.

“The results reveal that if the magma chamber is big enough, the overpressure caused by differences in density alone are sufficient to penetrate the crust above and initiate an eruption,” said Professor Carmen Sanchez-Valle of the Swiss Federal Institute of Technology (ETH) in Zurich, who led the study.

Preventing a supervolcanic eruption is not possible, but scientists are currently trying to devise methods of monitoring the pressure of underground magma in order to predict whether one is imminent.

Dr Perrillat said there are no known supervolcanoes that are in danger of erupting in the foreseeable future, and it would take at least a decade or so for the magma pressure within a caldera to build up to a point where an eruption is likely.

Life and Style
Small winemakers say the restriction makes it hard to sell overseas
food + drink
Arts and Entertainment
A comedy show alumni who has gone on to be a big star, Jon Stewart
tvRival television sketch shows vie for influential alumni
Arts and Entertainment
Carrie Hope Fletcher
booksFirst video bloggers conquered YouTube. Now they want us to buy their books
News
Clare Balding
peopleClare Balding on how women's football is shaking up sport
PROMOTED VIDEO
Arts and Entertainment
Damien Hirst
artCoalition's anti-culture policy and cuts in local authority spending to blame, says academic
Sport
premier leagueMatch report: Arsenal 1 Man United 2
Arts and Entertainment
Kirk Cameron is begging his Facebook fans to give him positive reviews
film
News
i100
Sport
Jonny May scores for England
rugby unionEngland 28 Samoa 9: Wing scores twice to help England record their first win in six
Life and Style
fashionThe Christmas jumper is in fashion, but should you wear your religion on your sleeve?
News
ebooksNow available in paperback
Arts and Entertainment
Jason goes on a special mission for the queen
tvReview: Everyone loves a CGI Cyclops and the BBC's Saturday night charmer is getting epic
Arts and Entertainment
Jerry Hall (Hand out press photograph provided by jackstanley@theambassadors.com)
theatre
Sport
Tony Bellew (left) and Nathan Cleverly clash at the Echo Arena in Liverpool
boxingLate surge sees Liverpudlian move into world title contention
Voices
Neil Findlay
voicesThe vilification of the potential Scottish Labour leader Neil Findlay shows how one-note politics is today, says DJ Taylor
Life and Style
food + drinkMeat-free recipes and food scandals help one growing sector
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Reach Volunteering: Financial Trustee and Company Secretary

Voluntary Only - Expenses Reimbursed: Reach Volunteering: A trustee (company d...

Recruitment Genius: Senior Project Manager

£45000 - £65000 per annum: Recruitment Genius: This is a fantastic opportunity...

Recruitment Genius: Shopfitter

Negotiable: Recruitment Genius: This is an opportunity to join a successful an...

Recruitment Genius: Digital Sales Account Manager

£25000 - £30000 per annum: Recruitment Genius: A Digital Sales Account Manager...

Day In a Page

Mau Mau uprising: Kenyans still waiting for justice join class action over Britain's role in the emergency

Kenyans still waiting for justice over Mau Mau uprising

Thousands join class action over Britain's role in the emergency
Isis in Iraq: The trauma of the last six months has overwhelmed the remaining Christians in the country

The last Christians in Iraq

After 2,000 years, a community will try anything – including pretending to convert to Islam – to avoid losing everything, says Patrick Cockburn
Black Friday: Helpful discounts for Christmas shoppers, or cynical marketing by desperate retailers?

Helpful discounts for Christmas shoppers, or cynical marketing by desperate retailers?

Britain braced for Black Friday
Bill Cosby's persona goes from America's dad to date-rape drugs

From America's dad to date-rape drugs

Stories of Bill Cosby's alleged sexual assaults may have circulated widely in Hollywood, but they came as a shock to fans, says Rupert Cornwell
Clare Balding: 'Women's sport is kicking off at last'

Clare Balding: 'Women's sport is kicking off at last'

As fans flock to see England women's Wembley debut against Germany, the TV presenter on an exciting 'sea change'
Oh come, all ye multi-faithful: The Christmas jumper is in fashion, but should you wear your religion on your sleeve?

Oh come, all ye multi-faithful

The Christmas jumper is in fashion, but should you wear your religion on your sleeve?
Dr Charles Heatley: The GP off to do battle in the war against Ebola

The GP off to do battle in the war against Ebola

Dr Charles Heatley on joining the NHS volunteers' team bound for Sierra Leone
Flogging vlogging: First video bloggers conquered YouTube. Now they want us to buy their books

Flogging vlogging

First video bloggers conquered YouTube. Now they want us to buy their books
Saturday Night Live vs The Daily Show: US channels wage comedy star wars

Saturday Night Live vs The Daily Show

US channels wage comedy star wars
When is a wine made in Piedmont not a Piemonte wine? When EU rules make Italian vineyards invisible

When is a wine made in Piedmont not a Piemonte wine?

When EU rules make Italian vineyards invisible
Look what's mushrooming now! Meat-free recipes and food scandals help one growing sector

Look what's mushrooming now!

Meat-free recipes and food scandals help one growing sector
Neil Findlay is more a pink shrimp than a red firebrand

More a pink shrimp than a red firebrand

The vilification of the potential Scottish Labour leader Neil Findlay shows how one-note politics is today, says DJ Taylor
Bill Granger recipes: Tenderstem broccoli omelette; Fried eggs with Mexican-style tomato and chilli sauce; Pan-fried cavolo nero with soft-boiled egg

Oeuf quake

Bill Granger's cracking egg recipes
Terry Venables: Wayne Rooney is roaring again and the world knows that England are back

Terry Venables column

Wayne Rooney is roaring again and the world knows that England are back
Michael Calvin: Abject leadership is allowing football’s age-old sores to fester

Abject leadership is allowing football’s age-old sores to fester

Those at the top are allowing the same issues to go unchallenged, says Michael Calvin