The Chicxulub Asteroid Impact and Mass Extinction
11 comments
·June 6, 2025InfiniteLoup
Google search (for those who are still using it) comes up with a funny little Easter egg when you search for "Chicxulub asteroid" or "Chicxulub crater".
QuinnyPig
Too soon.
pmontra
TL;DR
> The temporal match between the ejecta layer and the onset of the extinctions and the agreement of ecological patterns in the fossil record with modeled environmental perturbations (for example, darkness and cooling) lead us to conclude that the Chicxulub impact triggered the mass extinction.
which is exactly what everybody believes. Was it still controversial in 2010, the publishing year of the paper?
southernplaces7
As another response to your comment already covers, in the last few years, a fair bit of debate emerged questioning if the asteroid was just a contributing coup de grace after a prolonged period of vast, exinction-level climatic destruction.
This because the impactor arrived right around the same time in which the Deccan Traps (gigantic lava producing volcanic zones, like slow moving, continent-destroying lava flows basically) were apparently already in full swing, creating their own climatic havoc around the world.
Even now, enough evidence exists in favor of the Traps being at least a major cause of devastation at the time that it's hard to be sure.
Basically, it could be that the Traps were doing their thing and would have caused some high amount of species extinction all by themselves, but perhaps not as much extinction as did happen, or it could be that they could have caused a mass extinction by themselves but that the asteroid -even if the Traps had not been active- would have anyhow caused the mass extinction that happened at the time. Thus, though it's definitely known that the asteroid hit and caused global cataclysm, it's debated if this by itself would have been enough in the absence of the Deccan Traps.
Obviously, because the traps were already destroying ecosystems and species doesn't mean that the asteroid couldn't have caused mass extinction all by itself, and the speed at which species died off according to fossil strata does indicate the much more sudden asteroid effects as the main culprit, but the coincidence of both together does muddy the waters a bit, so to speak.
southernplaces7
Also, there has been some speculation that the asteroid actually caused the Deccan Traps to get much worse, since their location on the Indian subcontinent was at the time very close to being the antipode of the Chicxulub impact area, but i'm not sure if this has been dropped as a real theory now. If it were the case, then the asteroid would definitely be the main culprit, just in a more complex and dynamic way.
miramba
I think a competing theory was/is that the mass extinction was caused by volcanism of the Deccan-Traps, briefly mentioned in the abstract “…occurred within the time of Deccan flood basalt volcanism in India”. This article seems to confirm a direct relation between the meteorite impact and the extinction with the deccan traps activity possibly serving as a contributing factor.
timdiggerm
There are still paleontologists [who?](I do not know; I'm sorry) who would like to substantially credit the Deccan Traps; this appears to be adding stronger analysis to the evidence that it really was the meteor impact.
tim333
I like the idea that the Deccan Traps were caused by the meteor, being roughly on the opposite side of the earth so a spreading circular shock wave would come to a focal point on the other side of the globe. I'm not sure the dates quite match but who knows.
If anyone has 1hr 6min to kill, https://www.youtube.com/watch?v=ya3w1bvaxaQ is a fun watch. Someone simulated what the shockwave might have looked like.
It was a good day to be a burrowing species that hibernated and ate carrion.