Analysis: Dinosaur-killer impact threw up mountains taller than the Himalayas very briefly

Alessandra Kelley · Nov 17, 2016

http://www.bbc.com/news/science-environment-38019604

Scientists say they can now describe in detail how the asteroid that wiped out the dinosaurs produced its huge crater.

The reconstruction of the event 66 million years ago was made possible by drilling into the remnant bowl and analysing its rocks.

These show how the space impactor made the hard surface of the planet slosh back and forth like a fluid.

At one stage, a mountain higher than Everest was thrown up before collapsing back into a smaller range of peaks.

"And this all happens on the scale of minutes, which is quite amazing," Prof Joanna Morgan from Imperial College London, UK, told BBC News.

"Once we got through the impact melt on top, we recovered pink granite. It was so obvious to the eye - like what you would expect to see in a kitchen countertop," recalled Prof Sean Gulick from the University of Texas at Austin, US.

But these were not normal granites, of course. They were deformed and fractured at every scale - visibly in the hand and even down at the level of the rock's individual mineral crystals. Evidence of enormous stress, of having experienced colossal pressures.

The article includes an animation of a cross section of half the crater for the approximately ten minutes it took for the bolide impact to throw up gigantic mountains, which quickly collapsed and spread out.

Introversion · Nov 17, 2016

Wow. Glad to've missed that one.

King Neptune · Nov 17, 2016

Yes, I am also glad that I wasn't in the area.
Then there's this.
https://www.youtube.com/watch?v=b2S-IrZLbls

Alessandra Kelley · Nov 17, 2016

King Neptune said:
Yes, I am also glad that I wasn't in the area.
Then there's this.
https://www.youtube.com/watch?v=b2S-IrZLbls

Given the northwest-directed rain of acidic clay over the next few hours after impact, it really looks like all of North America was the area you wouldn't want to have been in.

blacbird · Nov 17, 2016

Alessandra Kelley said:
Given the northwest-directed rain of acidic clay over the next few hours after impact, it really looks like all of North America was the area you wouldn't want to have been in.

You wouldn't have wanted to be around anywhere on the planet. Not only were dinosaurs made extinct, everywhere, but so were most other big reptilian non-dinosaur groups, like pterosaurs, mososaurs, plesiosaurs and ichthyosaaurs. Plus ammonites, which dwelt in the upper portion of the water column in the oceans, and many other plant and animal groups. Curiously, crocodilians survived. And birds, the single surviving lineage from the dinosaur group.

caw

King Neptune · Nov 17, 2016

Alessandra Kelley said:
Given the northwest-directed rain of acidic clay over the next few hours after impact, it really looks like all of North America was the area you wouldn't want to have been in.

Yes, If I'd been on the planet, then I would have wanted to be in Australia.
L. Sprague de Camp wrote a time travel story about a group going back to watch from a long way off, Tennessee maybe, and they departed shortly after seeing the fireball.
http://www.baen.com/Chapters/9781625791115/9781625791115___3.htm

Alessandra Kelley · Nov 17, 2016

King Neptune said:
Yes, If I'd been on the planet, then I would have wanted to be in Australia.
L. Sprague de Camp wrote a time travel story about a group going back to watch from a long way off, Tennessee maybe, and they departed shortly after seeing the fireball.
http://www.baen.com/Chapters/9781625791115/9781625791115___3.htm

Tennessee, I believe, would have been within range of the initial tsunami (which could have possibly reached as far inland as Ohio).

I think they estimated the first airborne acid hit Colorado within twenty minutes, melting bedrock into a layer of clay.

And if, as some think, the impact generated clouds of sulfur trioxide, the top ten feet of all the Earth's oceans would have been something like lemonade in acidity within a day or two.

(All scientific claims based on muzzy memories of "T Rex and the Crater of Doom".)

Albedo · Nov 17, 2016

Hmm, a wave of liquid mountains, 10 kilometres high, approaching at nearly a kilometre a second. Anyone else thinking what I'm thinking? Woooo, surf's up!

jjdebenedictis · Nov 17, 2016

Oh, yeah. That's amazingly cool and amazingly scary.

Given it could happen again.

blacbird · Nov 18, 2016

jjdebenedictis said:
Oh, yeah. That's amazingly cool and amazingly scary.

Given it could happen again.

We like to think that this impact event was long ago, in a distant past. In terms of geologic age, it was around 65 million years ago. The planet is 4500 million years old. The math says that this even happened about 1.4% into our geologic past.

Like, geologically, purty recent.

caw

jjdebenedictis · Nov 18, 2016

blacbird said:
We like to think that this impact event was long ago, in a distant past. In terms of geologic age, it was around 65 million years ago. The planet is 4500 million years old. The math says that this even happened about 1.4% into our geologic past.

Like, geologically, purty recent.

caw

Oh, yeah. If there was oodles of complex life around when it happened, then it was definitely purty recent!

Analysis: Dinosaur-killer impact threw up mountains taller than the Himalayas very briefly

Alessandra Kelley

Sophipygian

Introversion

Pie aren't squared, pie are round!

King Neptune

Alessandra Kelley

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