Dino-killing asteroid could have thrust Earth into 2 years of darkness

or not.

There are two 300 km astroblemes in Australia, another 300 km astrobleme in Wilkesland, Antarctica and another 300-400 km meteor impact basin near the Falkland Islands. All four are tentatively dated to the 300 to 250 Mya. Each of these four craters is ~300km in diameter. End Permian dates to 252 Mya and is attributed to the Siberian Traps (a large outpouring of Basaltic Lava), not meteor impacts.

Chicxulub crater is ~180km in diameter.

https://www.nyu.e...est.html

The chicxulub meteor wasn't just another impactor, it hit in shallow seas and that made a huge difference in the spherules that started the fires. All those Permian impacts were deep water, and there was only one continent, populated with tougher, more naturally fringe living organisms, so, as usual, you're just spouting semi-validated data points, stringing them together, working backward from your a priori conclusion...only demonstrating that you're an objectionable, dotty old fart.

"End Permian dates to 252 Mya and is attributed to the Siberian Traps (a large outpouring of Basaltic Lava), not meteor impacts. "

There is a potential crater under the ice in Antarctica, detected using radar, that is also much larger than the Chicxulub crater, but is also on the opposite side of the world from where the Siberian traps were located at that time. The shock wave of impact would have gone through the earth and been concentrated at the Traps, potentially causing weakness in the crust that allowed the Traps to form in the first place. This was mentioned on an episode of 'What On Earth' on the Science channel.

Interesting article on impacts of impacts.

@Shootist; Ironhorse: Yes, none of the 5 major mass extinctions have been unarguably attributed. But impact events is considered minor plausibility in the others - including the through Earth refraction model, which is even fringe as far as I know - and specifically the end-Permian Siberian Trap correlation is increasingly robust. There was a recent paper that modeled the trap event phases to the dating of geological stages very precisely, for example.

Dino-killing asteroid could have thrust Earth into 2 years of darkness

or not.

There are two 300 km astroblemes in Australia, another 300 km astrobleme in Wilkesland, Antarctica and another 300-400 km[...]these four craters is ~300km in diameter. End Permian dates to 252 Mya and is attributed to the Siberian Traps (a large outpouring of Basaltic Lava), not meteor impacts.

Chicxulub crater is ~180km in diameter.

So what is your point, Shooty?

I don't even need to dispute or confirm any of your statements, as they are --every last one of them-- IRRELEVANT.

Chicxulub occurred ~66MYA, and wouldn't have been in any way affected by any effects of any of your precursors, the most recent of which --from your own comment-- occurred ~250MYA.

Incidentally, Siberian Traps also entrained the burning of vast amounts of hydrocarbons, which would have resulted in the creation of quite a bit of soot, much as they propose for the Chicxulub impact.

One would think a nuclear winter would kill off all life on the planet instead of being to pick and choose what lives as this is what fuels the folks on the History Channel's Ancient Aliens.

what/mammals/would/survive/impact/damage/plus/two/years/darkness?and/how?

Hey richk, I wonder...do any mammals live underground? You asked how, maybe that would help, ya think?

Hey richk, do you think any insects could have survived?
Fish maybe, crustaceans, how about molluscs or amphibians?
Are there any mammals that might eat some of the above?
Must have been a lot of dino carrion about and I imagine some flies and a bad smell.

Hey richk, do you think any insects could have survived?
Fish maybe, crustaceans, how about molluscs or amphibians?
Are there any mammals that might eat some of the above?
Must have been a lot of dino carrion about and I imagine some flies and a bad smell.

Think about all the fungus that must have flourished....

Fungusss, yum!

Must have been a rotten time to have lived through for our ancestors.

Sure it wasn't due to man-made global warming?

Sure it wasn't due to man-made global warming?

Scientists say Trump caused the extinction of the dinosaurs :D

@FM97, Trumpoids say scientists caused the extinction of the dinosaurs by discovering global warming.

There, fixed it for you.

Hey richk, I wonder...do any mammals live underground? You asked how, maybe that would help, ya think?

It sure would! However wouldn't be very hospitable for ANY other ones. Did we all make it here because of moles[...]
Two years of darkness would have extincted all ectotherms....that we have them still kinda blows a whole in the 2 years of darkness theory.

Well, biscuit, every school child knows --or should know-- that our mammalian ancestors were rodent-like, and only recently evolved late in the age of the dinosaurs, so that pretty much deals with that part of your comment.

No one has ever said that this period of darkness was complete, or that its effect was entirely uniform on a global scale, so that should settle the second and third parts of your comment.

Needless to say, it would only have taken a few survivors to then recolonize a planet full of now uncontested food resources following the proposed period of relative darkness.

Imagine fiery rain falling from the skies, back in the days.

Could an animal like a house cat survive this?

They don't swim that much, or go very deep when forced to, not really known for digging holes, burrows, they eat mostly meat, not big on fungi.

What do you think?

Well, there you go again, biscuit, interpreting to suit yourself. Nowhere in the article do they say that the effects were uniform, globally.

Are you aware of the meaning of the word average? or "could have"?

Do you think that if they meant global shut down of photosynthesis, that they would say so, instead of leaving it up to readers to interpret? Do you really think that there would be any marine plants in the ocean today if there had been a 100%, global shut down of photosynthesis? Do you mean to suggest that all marine plants extant have evolved since this impact occurred?

Do you question on what basis they claim global wildfires?

I don't suppose it matters. I made the unfortunate mistake of failing to qualify my assertion by adding that "no one(previously engaged in researching this event) said..." and
compounded the error by thinking you might possess any background understanding of this event.

Anyway, glad to have provided you with a fun time.

Well, then biscuit, thanks for clarifying that you were disagreeing with the article.

Also, you are, as I stated earlier, welcome for the fun.

Please allow me to return the favor, by providing you the answer to your earlier inquiry,

If you also want to go ahead and link us all to the evolutionary EVIDENCE transitioning subterranean rodentia to homosapiens that would be great...yeah...

While I don't recall making any claim regarding "subterranean", nevertheless, there's (Wiki, I know) this:

https://en.wikipe..._mammals

Indeed biscuit, all mammals --including Humans-- are descended from a small rodent-like progenitor.

While I don't recall making any claim regarding "subterranean", nevertheless, there's (Wiki, I know) this:

You didn't. Again, in the context of the article they would have been the only survivors. And unlike a lot of people here I don't mind links to Wiki...although I have read the one you provided a few times in the past for various references. I only referenced "subterranean" because the post of mine that you responded to had the quote from Bendbob about mammals that live underground.
Cheers

Hahaha!

Poor biscuit, reduced to a pathetic attempt to walkback an overstep.

No worries, biscuit.

I can certainly understand how, in your haste to ridicule, you took that one step too many.

Jeers!