"End-Permian extinction was instantaneous in geological time" Topic

So what could have caused the sudden, global wipeout? The leading hypothesis is that the end-Permian extinction was caused by massive volcanic eruptions that spewed more than 4 million cubic kilometers of lava over what is now known as the Siberian Traps, in Siberia, Russia. Such immense and sustained eruptions likely released huge amounts of sulfur dioxide and carbon dioxide into the air, heating the atmosphere and acidifying the oceans.

Prior work by Bowring and his former graduate student Seth Burgess determined that the timing of the Siberian Traps eruptions matches the timing of the end-Permian extinction. But according to the team's new data from the Penglaitan section, even though increased global volcanic activity dominated the last 400,000 years of the Permian, it doesn't appear that there were any dramatic die-outs of marine species or any significant changes in ocean temperature and atmospheric carbon in the 30,000 years leading up to the main extinction.

"We can say there was extensive volcanic activity before and after the extinction, which could have caused some environmental stress and ecologic instability. But the global ecologic collapse came with a sudden blow, and we cannot see its smoking gun in the sediments that record extinction," Ramezani says. "The key in this paper is the abruptness of the extinction. Any hypothesis that says the extinction was caused by gradual environmental change during the late Permian—all those slow processes, we can rule out. It looks like a sudden punch comes in, and we're still trying to figure out what it meant and what exactly caused it."

"This study adds very much to the growing evidence that Earth's major extinction events occur on very short timescales, geologically speaking," says Jonathan Payne, professor of geological sciences and biology at Stanford University, who was not involved in the research. "It is even possible that the main pulse of Permian extinction occurred in just a few centuries. If it turns out to reflect an environmental tipping point within a longer interval of ongoing environmental change, that should make us particularly concerned about potential parallels to global change happening in the world around us right now."

Read more at: link

Marty, how could one rule out another asteroid strike causing all this mayhem? A large enough object with sufficient momentum could penetrate the crust. This could be your mega-super-volcano.

Bowman, I see it as the other way around. There's renewed interest in the role of the Deccan Traps having a hand in the KT extinction event. Essentially, Chicxulub isn't needed as much as it was 10 years ago, and the evidence from the Deccan traps lines up better with what we know of global atmospheric circulation and evidence from the Siberian Traps and Permian extinction. Furthermore, the asteroid theory does not explain why dinosaurs were in decline prior to impact, whereas the Deccan trap can offer an explanation.

link

Whether the large thump that the Earth took in Chicxulub has some causal connection with the Deccan Traps, I'm out of my depth.

Hi Martin. Well finding the iridium and chromium isotope blast circumference at Chicxulub is pretty solid. So I think an asteroid blast is pretty probable. As you say, it doesn't explain why many of the dinosaurs were in decline before this. So other events must be in play.

But not so with the P-T event. All the species seem to have been doing well just prior to the event and the mass deaths seem to have occurred abruptly. So I'm not doubting that the Siberian Traps are the culprits. I'm just wondering how an asteroid strike can be ruled out in this case. It's doubtful that a nice iridium ring will ever be found from 250 million years ago. Especially if it's all underwater.

I read the article linked in original post. The discussion you both are having is fascinating. Geology has always been an interest of mine since a young age. (my mother had a degree in Geology from the University of Illinois) Attached is a short YouTube talk about the Permian extinction and the possible causes. One hypothesis is the asteroid strike that Bowman mentioned, not in the Siberia but in Antarctica. The short video explains how this hypothesis would work.
YouTube link

Terry

We find that on various levels individuals or groups can survive and even thrive in extreme conditions.

Many people of a certain age have quite a few afflictions that put tremendous strain upon their bodies, but they are fine, like the 99-year old who still uses a bike to get around, but then catches a bad cold and dies a week later because they have several major conditions that leave them wide open to die from minor issues.

Same with groups of animals, the best example being the Chernobyl exclusion zone. Most of the animals look fine, but their immune system is in permanent overdrive to stave off the effects of radiation, and all it takes is a minor disease or a small infection and the system overloads.

The Perm extinction may have been a similar problem where life held on under harsh conditions, adapted as much as possible, but any extra strain on the system caused entire species to die off, causing more extinctions that rippled over the whole planet until a handful of survivors have enough room to not only survive, but recuperate and over time thrive again long enough to diversify.

What does it take to trigger a "trap"?

I've read recently that some of the eruptions or strikes were worse because they came in on sulfate deposits. Supposedly, if the Chikxulub event had been a hundred miles north, and solely in the water, we would all be speaking Raptor today.
That struck me as making a horrible disaster a 99 instead of "only" a 95.
You're screwed regardless, but the sulfates make it a little bit worse.
Well, I did get it from Google News Science…..
Supposedly the Siberian Traps also came up under sulfates.

A while back, I read Lucifer's Hammer. Or was it The Mote in God's Eye?
Anyway, a comet hit the Earth, the Earth rang like a bell, and all tectonic faults let loose, stabilizing the Earth seismically for a few hundred years.
If it's good enough for a cracking yarn, it's good enough for me.

My original question from a few months ago applies. Are there any potential "traps" out there just waiting for a hit.

The Perm extinction may have been a similar problem where life held on under harsh conditions, adapted as much as possible, but any extra strain on the system caused entire species to die off, causing more extinctions that rippled over the whole planet until a handful of survivors have enough room to not only survive, but recuperate and over time thrive again long enough to diversify.

That's an excellent point. However, I'd say that pertains more to the K-T extinction just 66 million years ago. As Martin correctly states, it seems that dinosaurs en masse were already ailing with many species already extinct. The Chikxulub strike was just the "cold" that does in the 99 year bike rider.

From what we can tell about the earlier P-T event, this wasn't the case. I'm not sure "extreme conditions" existed during the end of the Permian. It seems things were coming along nicely since the Carboniferous Rainforest collapse about 50 million years before.

A while back, I read Lucifer's Hammer. Or was it The Mote in God's Eye?
Anyway, a comet hit the Earth,……

Lucifer's Hammer.

The Mote In God's Eye is an alien contact story with the Moties.

But not so with the P-T event. All the species seem to have been doing well just prior to the event and the mass deaths seem to have occurred abruptly. So I'm not doubting that the Siberian Traps are the culprits. I'm just wondering how an asteroid strike can be ruled out in this case. It's doubtful that a nice iridium ring will ever be found from 250 million years ago. Especially if it's all underwater.

There's some great research coming out of Alberta and Utah suggesting that the Siberian Traps toutched off a very large coal seam, creating a very large pulse of CO2 and SO2. The evidence is circumstantial, but it does explain the spike of lead and mercury in PT boundary rocks (You don't get these elements in volcanos). The mechanism of action is that the pulse of SO2 create a massive amount of acid rain, that kills the (almost) all the flora, and the lack of flora kills (almost) everything else.

Thanks, I think that is what Winston was alluding to.

The acid rain would at the same time kill off the majority of sea life too.

Terry

My original question from a few months ago applies. Are there any potential "traps" out there just waiting for a hit.

I thought I answered that then, but I'll repeat here. We don't know for sure. These are relatively rare events, but they look like they're associated to rifting events (decompression melting).

But given that these magma are ferromagnetic (due to magnetite and other iron-rich substances), they would show as either magnetic anomalies or gravitational anomalies the various satellite scans we've run over the past 60 years. So we're mostly safe… I guess ¯\_(ツ)_/¯.