Did a burning oil spill wipe out the dinosaurs?

July 15, 2016 by Nick Longrich, University Of Bath, The Conversation
Credit: Shutterstock

Sixty six million years ago, the dinosaurs suddenly disappeared, along with most of the species on the planet. The extinction occurred at precisely the same time that a giant asteroid struck the Earth. The fact that the two events happened at the same time makes it all but certain that the asteroid wiped out the dinosaurs, but just how did that extinction happen? Was it dust, shot into the sky, blocking out the sun? Acid rain produced by sulphur vaporised during the impact? An inferno of hot debris?

A new study may get us closer to solving this mystery. The asteroid struck the Yucatan Peninsula, a region with vast quantities of buried underground. New data shows that the burning of the oil produced billions of tons of soot, enough to dim the sun for years and lead to a decade of .

The Cretaceous-Paleogene (K-Pg) was severe, wiping out over 75% of all species, including not just dinosaurs but also many birds, mammals, snakes, lizards, plants, and even insects. It was global, hitting all continents and all oceans. And it was rapid, with species seeming to vanish overnight.

In 1979, physicist Luis Alvarez was trying to figure out just how much time the extinction took. He focused on a thin layer of clay – the K-Pg boundary – that marked the extinction. His clever idea was to look at iridium levels in the boundary clay. Iridium is a rare metal found primarily in meteorites, so the slow trickle of iridium from meteorites burning up in the atmosphere should act as a sort of cosmic hourglass, telling the passing of time.

His plan backfired spectacularly: iridium levels in the clay were orders of magnitude above the normal background levels. The K-Pg boundary was the debris of a giant asteroid impact. A few calculations suggested that it would take an asteroid 10 kilometres across to produce all that iridium. The idea that an asteroid wiped out the was widely ridiculed – but then, in 1990, the giant Chicxulub crater in Mexico was discovered.

Deep impact. Credit: Shutterstock

Global extinction

But how does an asteroid impact in Mexico cause a worldwide extinction? Alvarez read about the 1815 explosion of Tamboro. Sulphate gas shot into the atmosphere caused a volcanic haze that reflected sunlight. It lead to the "Year Without a Summer", when freezing temperatures in summer lead to widespread crop failures and famine. Alvarez proposed that debris from Chicxulub had blocked out the sun. Without the sun, plants and plankton couldn't make food and the entire ecosystem starved.

It was a clever idea but studies of the K-Pg boundary revealed a problem. The debris was mostly coarse and would have dropped out out of the sky in a matter of a few months or weeks – not long enough to starve giant dinosaurs. There wasn't enough fine debris that could stay aloft for years to cause an extinction. So what did?

A new study by Kunio Kaiho and colleagues published in the journal Scientific Reports suggests a possible explanation. The K-Pg boundary contains soot. Although originally thought to be produced by wildfires, studies of its chemistry suggest that it is actually derived from burning hydrocarbons (crude oil). This fact seems puzzling until you consider that the Gulf of Mexico contains vast oil reserves. The Jurassic Cantarell oil field, the largest in Mexico, is nearby and, in fact, the Chicxulub crater was only discovered because geologists were mapping the area in search of oil.

As the Chicxulub asteroid tore into the earth, it released the oil locked in the rock. The Deepwater Horizon spill produced 4.9 million barrels of oil from just a tiny hole in the ocean floor. The Chicxulub crater was 180 kilometers across. The intense heat of the impact would have burned the oil to create clouds of black soot and shot them into the stratosphere. Critically, tiny soot particles can stay up in the atmosphere for years. But was there enough to block out the ?

The researchers from Tohoku University in Japan studied the chemistry of soot at the K-Pg boundary and then estimated the amount of soot produced by impact. The total burned carbon produced was on the order of 1.8 to 60 billion tons.

Oil field on fire. Credit: Jonas Jordan/Wikimedia Commons

Dark and cold

They then used computer models to estimate the effects on the climate. Their models showed that the soot would have been highly effective in blocking light. Depending on the amount of soot, sunlight would have been reduced by 50% to 90%, and the global temperature would have cooled by between 6°C and 18°C, with cooling being especially severe towards the poles. Cooler temperatures would have also reduced rainfall, leading to widespread drought.

Critically, the cloud would stay aloft for years. The darkness and cooling were most severe in the first few years, but it would have taken a decade for light levels to slowly return to normal, and even longer for the climate to return to normal.

The research also helps put a time limit on the dinosaur extinction, suggesting the bulk of it took place in a span of less than ten years.

It's probably too soon to say that we have definitively solved the extinction puzzle. Science is rarely that neat and tidy. The nature of science is that, at best, we need to run more analyses and collect more data to confirm new finds, and at worst, it's full of seemingly promising dead ends.

But the new study is one of the most exciting developments in years, and it suggests that we may be closer to finally understanding the extinction of the dinosaurs. It may be that their extinction was caused by pollution and climate change caused by burning oil.

This could also explain why other asteroid impacts aren't associated with mass extinctions. It may have been the unlucky coincidence of a huge oil field and a giant asteroid impact that made Chicxulub so deadly. And there is a certain irony in the possibility that the same oil that did in the dinosaurs is now being used to run our own civilization – and perhaps threatening it as well.

Explore further: How does an invisible underwater crater prove an asteroid killed the dinosaurs?

More information: Kunio Kaiho et al. Global climate change driven by soot at the K-Pg boundary as the cause of the mass extinction, Scientific Reports (2016). DOI: 10.1038/srep28427

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31 comments

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antigoracle
1.8 / 5 (14) Jul 15, 2016
What complete and utter bullshit!!
Anything to support the AGW Cult's agenda can make it pass their pal-review.
Phys1
4.7 / 5 (13) Jul 15, 2016
@antisciencechucky
Man you are evil. And wrong.
The man has proof that the soot was from burning petrol.
Ever heard of Gulf Oil? Named after the Gulf of Mexico.
Look that up on the map. It's near Yucatan.
amiabledunce
1 / 5 (11) Jul 15, 2016
Don't think we need to go so far back-of course we just know the people of Mesoamerica didn't know what they were writing. Just a bunch of human-sacrificing, hallucinogenic- taking savages right?

The sacred book of the Mayas, the Popul Vuh, says: "It was ruin and destruction... the sea was piled up... it was a great inundation... people were drowned in a sticky substance raining from the sky... the face of the earth grew dark and the gloomy rain endured days and nights... and then there was a great din of fire above their heads." The entire population was annihilated. Other Central American myths contain stories of a deluge of sticky rain of bitumen from heaven; men were seized by madness and tried to escape it by sheltering in caverns but the caverns were suddenly closed. The cataclysm was preceded by a collision of stars and was followed by an inundation of the sea.
Phys1
4.7 / 5 (12) Jul 15, 2016
The Maya's did not yet exist 65 million years ago.
amiabledunce
Jul 15, 2016
This comment has been removed by a moderator.
gkam
Jul 15, 2016
This comment has been removed by a moderator.
Maggnus
4.6 / 5 (11) Jul 15, 2016
Neither did that burning oil.

Are you reading the same article?
Phys1
4.6 / 5 (11) Jul 16, 2016
Neither did that burning oil.

Why was there no oil 65 million years ago ?
Benni
1.6 / 5 (7) Jul 16, 2016
Wait, wait just a minute here...........if burning "oil" did the deed in causing the extinction, and if oil is a fossil fuel derived from the decayed carcasses of dinosaurs, then where did the oil come from in the first place? Timeline here:

.....................we're expected to believe that during the entire era of dinosaurs that upon the death of a dinosaur their carcasses by some sort of magic instantly turns into oil? That's the depiction the author presents in the picture., dinosaur dies, oil shows up on the surface of the ground & burns up the remaining population of the critters & that's how we get oil today pumped up from thousands of feet from underground.

gkam
2.8 / 5 (9) Jul 16, 2016
benni, did you REALLY ask that?

Are you unaware how many millions of years we had plants and no dinosaurs? Oil is from decomposed plants, benni, not animals.
Benni
2 / 5 (8) Jul 16, 2016
benni, did you REALLY ask that?

Are you unaware how many millions of years we had plants and no dinosaurs? Oil is from decomposed plants, benni, not animals.


No geek, you don't know what you're talking about.

Coal is a fossil fuel derived ONLY from vegetation sources. Oil that is pumped from thousands of feet underground does not originate from vegetation, therefore cannot be a fossil fuel if the Author's timeline is assumed to be correct. I don't need Differential Equations to do this math.
Da Schneib
4.4 / 5 (9) Jul 16, 2016
Let's see what Shell Oil has to say about it:

http://www.shell....-ch1.pdf

The oil and gas deposits started forming about 350 to 290 million years ago during the Carboniferous Period, which gets its name from the basic element in oil and gas: carbon. A popular belief is that oil comes from dead dinosaurs. It doesn't. The giant reptiles lived mostly from 250 to 65 million years ago, and most scientists believe oil actually comes from the tiniest plants and animals that preceded them.
Phys1
4.5 / 5 (8) Jul 16, 2016
Wait, wait just a minute here...........if burning "oil" did the deed in causing the extinction, and if oil is a fossil fuel derived from the decayed carcasses of dinosaurs,

You lost me at this point. Where do you get that information?
Phys1
4.6 / 5 (9) Jul 16, 2016
benni, did you REALLY ask that?

Are you unaware how many millions of years we had plants and no dinosaurs? Oil is from decomposed plants, benni, not animals.


No geek, you don't know what you're talking about.

Coal is a fossil fuel derived ONLY from vegetation sources. Oil that is pumped from thousands of feet underground does not originate from vegetation, therefore cannot be a fossil fuel

Perhaps some stuff was deposited on top in the past 250 million years?
I don't need Differential Equations to do this math.
Fortunately because you cant do math, as everybody knows.
I do admire your consistency.
All you need to change is to be consistently right instead of wrong.
Benni
1.5 / 5 (8) Jul 16, 2016
Well, what have we here, the BH Perpetual Motion Math guys who don't know oil & gas formations are continuously being formed underground today.

Maybe you Perpetual Motion Math slogs can tell us all about the little animals & vegetative stuff living thousands of feet underground today, dies, then becomes oil?

I get it, you have a picture of a hollow interior of the planet just teeming with life forms which decay upon death & just sort of percolates from up through the mantle & into the sedimentary layer to form oil & gas. I can see why none of you made to Differential Equations & Phys1 didn't get past 1st semester physics.

Da Schneib
4.5 / 5 (8) Jul 16, 2016
oil & gas formations are continuously being formed underground today
Oh, look there, @Lenni is an abiogenic oil crank, too.
Phys1
4.4 / 5 (7) Jul 16, 2016
Well, what have we here, the BH Perpetual Motion Math guys who don't know oil & gas formations are continuously being formed underground today.

Benni, you make Shell look stupid.
Either you are extremely brilliant, outshining the universe as we know it or you are an utter moron. I vote for the latter but I know you are convinced of the first.
Maybe you Perpetual Motion Math slogs can tell us all about the little animals & vegetative stuff living thousands of feet underground today, dies, then becomes oil?

Easily, there aren't any.
I get it, you have a picture of a hollow interior of the planet just teeming with life forms which decay upon death & just sort of percolates from up through the mantle & into the sedimentary layer to form oil & gas.

That is why you are committed.
I can see why none of you made to Differential Equations & Phys1 didn't get past 1st semester physics.

You probably see many things. Do you also hear voices?
antigoracle
1 / 5 (7) Jul 16, 2016
oil & gas formations are continuously being formed underground today
Oh, look there, @Lenni is an abiogenic oil crank, too.

A tiny insight into the even tinier mind of the consummate mouth breather. You must take pity, for such simple spewings do take their toll but provides it with those desperately needed moments of bliss.
Da Schneib
4.4 / 5 (7) Jul 16, 2016
Hey, they're poppin' out all over the place, @boreacle is another abiogenic oil crank.

You guys prolly don't "believe in" the Apollo Moon landings, either. Every crank theory on the 'Net seems to find its way into your teeny tiny minds.
Phys1
4.3 / 5 (6) Jul 16, 2016
oil & gas formations are continuously being formed underground today
Oh, look there, @Lenni is an abiogenic oil crank, too.

A tiny insight into the even tinier mind of the consummate mouth breather. You must take pity, for such simple spewings do take their toll but provides it with those desperately needed moments of bliss.

Can you translate that into English, Drama Queen?
antigoracle
1 / 5 (6) Jul 16, 2016
You guys prolly don't "believe in" the Apollo Moon landings, either.

LOL.
A mouth breather doing what it does best, just parroting the catechisms fed to it by the AGW Cult and incapable of realizing that they are designed to nurture its condition.
Phys1
4.3 / 5 (6) Jul 16, 2016
You guys prolly don't "believe in" the Apollo Moon landings, either.

LOL.
A mouth breather doing what it does best, just parroting the catechisms fed to it by the AGW Cult and incapable of realizing that they are designed to nurture its condition.

Can you translate that into English, Drama Queen?
Steve 200mph Cruiz
5 / 5 (8) Jul 17, 2016
Antigoracle

The largest mass extiction in history was probably caused by massive coal/oil deposits in Siberia catching fire at the end of the Permian.

During the previous periods, the Ordovician, the Devonian, and carboniferous, land plants evolved for the first time.
CO2 levels were much higher back then, and the planet was warmer and effectivelily the entire plane was covered in rain forest, there was no ice caps.
During the Permian, all those forests CO2 levels dropped to level comparable to today, albiet a little higher, and ice caps formed. All that carbon, vast amounts was stored in oil and gas, and most of the fossil fuel beds that exist today are still remnants of those ancient first forests, hence the name "Carboniferous".

Oh wait... you don't care
Caliban
4.2 / 5 (5) Jul 17, 2016
While there is merit to the proposition of these researchers, this remains mere hypothesis.

The only way to (largely) confirm it would be to drill bores across the entire extent(and beyond) of the impact crater. While it is true that the region features vast petroleum deposits, it doesn't necessarily follow that the asteroid plowed right into one of them.

And no --oil company records can't be used to reconstruct the stratigraphy, since they use a different drilling method, which isn't designed to preserve core samples.

It is also entirely possible --maybe even likely-- that this massive impact triggered some secondary effects by way of vulcanism and earthquakes, which may have produced or added to these theorized effects.
jonesdave
4.3 / 5 (6) Jul 18, 2016
AntigoracleThe largest mass extiction in history was probably caused by massive coal/oil deposits in Siberia catching fire at the end of the Permian.


No offence old chap, but I think you'll find that the Siberian Traps are due to a flood basalt episode. Similar to the Deccan Traps, but considerably greater in extent. Never heard of this coal/ oil thingy.
jonesdave
4 / 5 (4) Jul 18, 2016
You guys prolly don't "believe in" the Apollo Moon landings, either.

LOL.
A mouth breather doing what it does best, just parroting the catechisms fed to it by the AGW Cult and incapable of realizing that they are designed to nurture its condition.


Somebody translate that into English, and explain what it means. Please!
jonesdave
3.8 / 5 (4) Jul 18, 2016
Well, what have we here, the BH Perpetual Motion Math guys who don't know oil & gas formations are continuously being formed underground today.

Maybe you Perpetual Motion Math slogs can tell us all about the little animals & vegetative stuff living thousands of feet underground today, dies, then becomes oil?

I get it, you have a picture of a hollow interior of the planet just teeming with life forms which decay upon death & just sort of percolates from up through the mantle & into the sedimentary layer to form oil & gas. I can see why none of you made to Differential Equations & Phys1 didn't get past 1st semester physics.



Jeez, this guy is a serious f*ckw*t, eh?
jonesdave
4 / 5 (4) Jul 18, 2016
Wait, wait just a minute here...........if burning "oil" did the deed in causing the extinction, and if oil is a fossil fuel derived from the decayed carcasses of dinosaurs, then where did the oil come from in the first place? Timeline here:

.....................we're expected to believe that during the entire era of dinosaurs that upon the death of a dinosaur their carcasses by some sort of magic instantly turns into oil? That's the depiction the author presents in the picture., dinosaur dies, oil shows up on the surface of the ground & burns up the remaining population of the critters & that's how we get oil today pumped up from thousands of feet from underground.



Yep, my previous comment was right; this guy seriously is a f*ckw*t.
jonesdave
4.2 / 5 (5) Jul 18, 2016
Come on, Benni, you can't be that thick! You do realise that all the gas and oil beneath Antarctica is due to dead Penguins. Right?
BongThePuffin
Jul 20, 2016
This comment has been removed by a moderator.
OdinsAcolyte
1 / 5 (2) Jul 21, 2016
Petroleum has rescued out civilization you brainwashed silly person.
Politics is ruining our culture. From climate change to this kind of crap.
Those who teach this mode of thought can find nothing good in mankind. Remember we too are the hand of nature. We change the world and it changes us. Just had get that little BS political jab in at the end. Ruining an other wise enlightening paper with that baloney. Stick to science or get an opposing opinion back when you toss one out. I can balance much more good on the petrochemical side than bad. Extend your knowledge past your politics.

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