Huge asteroid impact 250 million years ago key to mass extinction

A massive asteroid bigger than Mount Everest slammed into the earth 250 million years ago causing the greatest mass extinction on record, say the scientists who believe they have found the "smoking gun" of the collision.

Geologists located the huge undersea crater off the Australian coast where they think the asteroid hit with the force of 1 million nuclear bombs, an impact that almost snuffed out life on earth. About 90 per cent of marine organisms and 80 per cent of land animals and plants died out at the end of the Permian and the beginning of the Triassic periods, for reasons that had not been explained.

If the asteroid impact is confirmed as the cause of the "great dying", it will be the second example of an extraterrestrial object being linked with a mass extinction. The other was the demise of the dinosaurs some 65 million years ago.

Luann Becker, of the University of California at Santa Barbara, and colleagues at the Australian National University in Canberra said that they have gathered extensive evidence of a 125-mile wide crater off the north-west coast of Australia.

Dr Becker said that her team had found fragments of a meteor in a geological layer that corresponded to the date of the Permian mass extinction 250 million years ago.

Analysis of geological cores drilled by oil companies prospecting in the region had also revealed convincing data to suggest that the crater was created by a massive object from outer space.

The scientists have found melted rock and shocked-quartz crystals that contain the tell-tale fractures that they believe are the result of a cataclysmic collision involving a huge explosive force. "Few earthly circumstances have the power to disfigure quartz, even high temperatures and pressures deep inside the earth's crust," Dr Becker said.

The study, published in Science journal, relied on two oil-company cores drilled in the Seventies and Eighties through a geological feature called "The Bedout High", which had not been previously analysed.

When the scientists started to investigate the cores, which had been stored untouched by the Geological Survey of Australia, they soon realised that they had probably been drilled through an impact crater.

The great dying at the end of the Permian period is the greatest of the five known mass extinctions. No type of life was spared: plants, insects, reptiles, fish, molluscs and microbes were all affected.

Some scientist have suggested that severe volcanic eruptions at the time may have sent soot and ash into the atmosphere and shut out the sunlight for years. Others have suggested that climate change, brought about by the formation of a giant supercontinent, was the cause.

Originally it was thought that the mass extinction took place over millions of years but more recent studies suggest that could have occurred in less than 10,000 years - a very short period in geological history.

"I think palaeontologists are now coming full circle and leading the way in saying that the extinction was extremely abrupt," Dr Becker said.

A similar impact crater has been found at Chicxulub in Mexico, which scientists have dated to about 65 million years ago - the time when the dinosaurs became extinct - which was also marked by a period of intense volcanic activity.

Dr Becker added: "We think that mass extinctions may be defined by catastrophes like impact and volcanism occurring synchronously. With the discovery of the Bedout I don't think we can call such catastrophes occurring together a coincidence any more."

PROMOTED VIDEO
News
ebookA unique anthology of reporting and analysis of a crucial period of history
News
Richard Norris in GQ
mediaGQ features photo shoot with man who underwent full face transplant
News
Gardai wait for the naked man, who had gone for a skinny dip in Belfast Lough
newsTwo skinny dippers threatened with inclusion on sex offenders’ register as naturists criminalised
News
Your picture is everything in the shallow world of online dating
i100
News
The Swiss Re tower or 'Gherkin' was at one time the UK’s most expensive office when German bank IVG and private equity firm Evans Randall bought it
news
Life and Style
Attractive women on the Internet: not a myth
techOkCupid boasts about Facebook-style experiments on users
Independent
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
santorini
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
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

Embedded Linux Engineer

£40000 - £50000 per annum + competitive: Progressive Recruitment: Embedded Sof...

Senior Hardware Design Engineer - Broadcast

£50000 - £65000 per annum + Benefits: Progressive Recruitment: Working for a m...

Reconciliation Analyst

£200 - £250 per day: Orgtel: Reconciliation Analyst Gloucestershire

Soutions Architect TOGAF - Reading

£60000 - £80000 per annum + Excellent Corporate Benefits: Progressive Recruitm...

Day In a Page

The children were playing in the street with toy guns. The air strikes were tragically real

The air strikes were tragically real

The children were playing in the street with toy guns
Boozy, ignorant, intolerant, but very polite – The British, as others see us

Britain as others see us

Boozy, ignorant, intolerant, but very polite
Countries that don’t survey their tigers risk losing them altogether

Countries that don’t survey their tigers risk losing them

Jonathon Porritt sounds the alarm
How did our legends really begin?

How did our legends really begin?

Applying the theory of evolution to the world's many mythologies
Watch out: Lambrusco is back on the menu

Lambrusco is back on the menu

Naff Seventies corner-shop staple is this year's Aperol Spritz
A new Russian revolution: Cracks start to appear in Putin’s Kremlin power bloc

A new Russian revolution

Cracks start to appear in Putin’s Kremlin power bloc
Eugene de Kock: Apartheid’s sadistic killer that his country cannot forgive

Apartheid’s sadistic killer that his country cannot forgive

The debate rages in South Africa over whether Eugene de Kock should ever be released from jail
Standing my ground: If sitting is bad for your health, what happens when you stay on your feet for a whole month?

Standing my ground

If sitting is bad for your health, what happens when you stay on your feet for a whole month?
Commonwealth Games 2014: Dai Greene prays for chance to rebuild after injury agony

Greene prays for chance to rebuild after injury agony

Welsh hurdler was World, European and Commonwealth champion, but then the injuries crept in
Israel-Gaza conflict: Secret report helps Israelis to hide facts

Patrick Cockburn: Secret report helps Israel to hide facts

The slickness of Israel's spokesmen is rooted in directions set down by pollster Frank Luntz
The man who dared to go on holiday

The man who dared to go on holiday

New York's mayor has taken a vacation - in a nation that has still to enforce paid leave, it caused quite a stir, reports Rupert Cornwell
Best comedians: How the professionals go about their funny business, from Sarah Millican to Marcus Brigstocke

Best comedians: How the professionals go about their funny business

For all those wanting to know how stand-ups keep standing, here are some of the best moments
The Guest List 2014: Forget the Man Booker longlist, Literary Editor Katy Guest offers her alternative picks

The Guest List 2014

Forget the Man Booker longlist, Literary Editor Katy Guest offers her alternative picks
Jokes on Hollywood: 'With comedy film audiences shrinking, it’s time to move on'

Jokes on Hollywood

With comedy film audiences shrinking, it’s time to move on