Posted on 03/20/2008 1:49:58 PM PDT by NormsRevenge
LONDON (Reuters) - Gas-belching volcanoes may be to blame for a series of mass extinctions over the last 545 million years, including that of the dinosaurs, new evidence suggested on Thursday.
A series of eruptions that formed the Deccan Traps in what is now India pumped huge amounts of sulfur into the atmosphere 65 million years ago, with likely devastating repercussions for the Earth's climate, scientists said.
Gigantic eruptions, forming so-called "flood basalts," are one of two leading explanations for a series of mass extinctions that have killed off species periodically throughout history.
The other theory involves asteroid impacts -- generally considered the prime suspect in the case of the extinction of dinosaurs 65 million years ago.
There have been doubts about the killing power of volcanoes because, until now, researchers have struggled to measure just how much toxic gas would have been released.
But after finding rare inclusions of glass in the Deccan rock, a British-based team has found vital preserved information about its original gas content.
Writing in the journal Science, they concluded that the massive of amounts of both sulfur and chlorine released would probably have had a "severe" environmental impact.
"It certainly bolsters the case, though it doesn't prove it," Stephen Self, formerly of Britain's Open University and now senior volcanologist with the U.S. Nuclear Regulatory Commission, said in an interview.
"There have been several major mass extinctions and most of those have, uncannily, occurred while one of these huge flood basalt provinces was being formed."
The volcanoes may have spewed 10 times as much sulfur into the atmosphere every year as humans have done recently by burning coal in power stations and through other industrial activities.
The result would have been widespread acid rain and aerosols of sulfuric acid in atmosphere, cooling the surface of the Earth and upsetting normal patterns of circulation.
Thanks NormsRevenge.
Asteroids:
Deadly Impact
National Geographic
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If the gas belching dinosaurs don’t get you, the volcanos will.
Some scientists contend that a supervolcano was about to explode, but it was plugged up just in the nick of time by an incoming asteroid.
It’s been proposed that big impacts cause volcanism on the OPPOSITE side of the earth through focusing of seismic energy there.
Very controversial though.
Shurlie you jest?
I think there was a recent topic about this.
Thanks! .. which is why I stuck it in chat and not
Breaking. 8-)
Well the Earth isn’t solid. If you look at it as a ball full of liquid that you shoot with a bullet, the reaction might occur anywhere on it’s surface due to it’s irregularity.
S aurian
U vented
V olcanos
That killed the Dinosaurs
YEC INTREP
I was thinking the same thing. You would think that a sufficiently massive strike would cause shock waves through the mantle that would trigger earthquakes and eruptions
The timing isn't all that clear (yet) but I wouldn't be a bit surprised to find that an impact large enough to ring the planet like a bell could trigger massive vulcanism.
I suspect magma may be somewhat thixotropic and flow to the surface much more easily under immediate post impact conditions.
I also think an impact would jar out dissolved gases and 'pump' magma towards the surface. Compare to what you see in a sealed soda bottle when you smack it one!
Then there's the really bad part.
The ocean rushes in and tries to fill a 100 km wide white hot crater.
Now instead of passively radiating the excess heat out into space like a dry land strike would, the crater flashes untold cubic kilometers of salt water into steam. Not only does this pretty much steam clean the entire earth's surface, it also rains salt out onto everything, so most plants can't grow even if their seeds managed to survive all the above excitement.
And prosecute all those would seek them out or speak of them.
For the children, the children.
Yeah, just by accident...
Watch/Read “Privileged Planet” and read “Case for a Creator”.
Super volcano!
Deccan traps!
Volcanoes right, left & center!
Comet collision!
Super-super nova radiation burst!
Space alien trophy hunters!
Earl Sinclair’s tree-hating boss!
Should-ah, could-ah, would-ha! (Yes; it COULD-AH!)
Shusshusshusshusshucka-duck! (Gooey duck a day!)
Shhh-BOOM; shhh-Boom! (Ce’si bon! Va-voom!)
Should-ah, could-ah, would-ah; (Yes, you should-ah!)
Coulda, coulda, coulda... (Yes, I would-ah!)
Would-ah done the ROOT-ah-BEG-gah BOOGIE!
you can have the gooey duck
I’ll just have the rutabaga
with a splash of comet dust
Thank You. ;-)
Maybe Suunk'll bring a fish to the beach party.
One cleaned gooey duck, stuffed with a topless, skinless rutabaga, and that stuffed into a large turbot, we could have a tubrutaduck.
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