Did a massive volcanic eruption in India kill off the dinosaurs?

There's a solid consensus among scientists about what happened to the dinosaurs 66 million years ago: A mountain-sized meteorite crashed into the planet and triggered a mass extinction. The debris from the impact has been found in hundreds of locations around the world. Geologists have also found signs of the giant crater, centered around the tip of Yucatan Peninsula.

But there has long been an alternate theory, espoused by a rump caucus of researchers who think they’ve never been given a fair hearing. They believe the extinction was caused, at least in part, by an extraordinary volcanic eruption in India.

This eruption created the Deccan Traps, a geological formation that covers nearly 200,000 square miles of western India. It was created by a flood of basaltic lava, the kind of eruption seen today on the Big Island in Hawaii. But the eruption that formed the Deccan Traps was unusually prolonged and prodigious. All told, the eruption produced about 1.3 million cubic kilometers of lava, which is about 1.3 million times as much material produced by the 1980 eruption of Mount St. Helens. The eruption pumped enormous, climate-changing quantities of carbon dioxide and sulfur dioxide into the atmosphere.
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Made of Stars wrote:....

Both should be a warning to us to get on with sorting our shit out, and getting out of this single little lifeboat.

Made of Stars wrote:The either-or / primary-secondary cause dichotomy is tiresome. If the Deccan traps event was contemporaneous with the Chicxulub event, then the dinosaurs were even more fucked than with either alone. End of.

Both should be a warning to us to get on with sorting our shit out, and getting out of this single little lifeboat.

DavidMcC wrote:

Made of Stars wrote:....

Both should be a warning to us to get on with sorting our shit out, and getting out of this single little lifeboat.

Sadly, Made of Stars, this is the only "lifeboat" we're going to get. Only those who believe in the Star Trek fantasy think otherwise.

Made of Stars wrote:

DavidMcC wrote:

Made of Stars wrote:....

Both should be a warning to us to get on with sorting our shit out, and getting out of this single little lifeboat.

Sadly, Made of Stars, this is the only "lifeboat" we're going to get. Only those who believe in the Star Trek fantasy think otherwise.

Sadly, DavidMcC, that's a self-fulfilling prophecy. One that we'd be wise to ignore, if we don't want to go the way of the dinosaur.

kennyc wrote:

Made of Stars wrote:

DavidMcC wrote:

Made of Stars wrote:....

Both should be a warning to us to get on with sorting our shit out, and getting out of this single little lifeboat.

Sadly, Made of Stars, this is the only "lifeboat" we're going to get. Only those who believe in the Star Trek fantasy think otherwise.

Sadly, DavidMcC, that's a self-fulfilling prophecy. One that we'd be wise to ignore, if we don't want to go the way of the dinosaur.

Yep, defeatist. We've already sent a few probes out, we are reaching, grasping, straining for Mars. If we can manage to survive a few more centuries we may be okay, but I do think we are at a critical phase in the evolution of life.

Rumraket wrote:Of relevance:



Basically the theory goes that the energy from the Chicxulub impact event was geometrically focused such that the shockwave generated from the impact traveled around the Earth and through the crust and mantle, being focused into a point on the opposite side of the globe, which 65 million years ago, happened to be where India was. So the Dinosaurs were wiped out, presumably according to this theory, through a combination of the K-T impact event and the subsequent extreme volcanism it produced in India.

Rumraket wrote:Of relevance:



Basically the theory goes that the energy from the Chicxulub impact event was geometrically focused such that the shockwave generated from the impact traveled around the Earth and through the crust and mantle, being focused into a point on the opposite side of the globe, which 65 million years ago, happened to be where India was. So the Dinosaurs were wiped out, presumably according to this theory, through a combination of the K-T impact event and the subsequent extreme volcanism it produced in India.

laklak wrote:It was Teh Flud, you atheist heretics.

laklak wrote:God pissed.

Rumraket wrote:Of relevance:

Basically the theory goes that the energy from the Chicxulub impact event was geometrically focused such that the shockwave generated from the impact traveled around the Earth and through the crust and mantle, being focused into a point on the opposite side of the globe, which 65 million years ago, happened to be where India was. So the Dinosaurs were wiped out, presumably according to this theory, through a combination of the K-T impact event and the subsequent extreme volcanism it produced in India.

DavidMcC wrote: However, it is claimed that the dinosaurs were already going extinct, before the Chicxulub event.

laklak wrote:God pissed.

susu.exp wrote:

Rumraket wrote:Of relevance:

Basically the theory goes that the energy from the Chicxulub impact event was geometrically focused such that the shockwave generated from the impact traveled around the Earth and through the crust and mantle, being focused into a point on the opposite side of the globe, which 65 million years ago, happened to be where India was. So the Dinosaurs were wiped out, presumably according to this theory, through a combination of the K-T impact event and the subsequent extreme volcanism it produced in India.

Except that the Deccan traps were active before the impact hit. There are intertrap sediments with the Iridium anomaly.
The extinction scenario driven by volcanism still seems unlikely, because flood basalts simply don't release massive amounts of CO2 (the total CO2 emissions from the deccan traps were lower than anthropogenic emmission were in 2013 and 2014 combined) and the total SO2 output of the traps is about the same as the human emissions per decade(see Self et al. 2006).
If volcanism played a causal role, it's not in the production of either CO2 or SO2.

DavidMcC wrote: However, it is claimed that the dinosaurs were already going extinct, before the Chicxulub event.

And the response to that always has to be: Can you show this? Do you have data that shows a decline that can be distinguished from backsmearing?

DavidMcC wrote:I am relying on what I read in the scientific press, many years ago. I did not keep the reference, but I DO remember the claim. I think it was separate evidence, related to your own point about the flood basalt s starting before the Chicxulub impact. I thought that YOU would have the evidence!

susu.exp wrote:

DavidMcC wrote:I am relying on what I read in the scientific press, many years ago. I did not keep the reference, but I DO remember the claim. I think it was separate evidence, related to your own point about the flood basalt s starting before the Chicxulub impact. I thought that YOU would have the evidence!

I don't doubt that the claim has appeared in the literature. But I has never really been substantiated. Backsmearing is an effect that arises from the temporal imprefection of the fossil record - you generally don't get the last member of a species as a fossil. You can do statistical tests for this, though and they are rarely done by dinosaur people. It has been done for various groups of mollusks, where you can not distinguish the appearent gradual decline from a geologically instantaneous event. It has been done for microfossils where the decline happens in a sedimentary range that's often only mms below the boundary, or even precisely on it. I've recently had that type of discussion with somebody working on pterosaurs and his view was that the record of pterosaurs was too incomplete to allow the use of statistics. He strongly favoured a model of decline prior to the KT boundary, based on the raw data. For some reason there are quite a few people who think that an insignificant result combined with a low sample size implies certainty...

Basically, the worse the temporal resolution of the fossil record gets for a group the more likely people working on that group have not considered that the pattern they observe might be an artifact of the low temporal resolution of the fossil record.