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Judi Lynn

(160,523 posts)
Tue Jul 20, 2021, 10:14 PM Jul 2021

52-foot-tall 'megaripples' from dinosaur-killing asteroid are hiding under Louisiana

By Laura Geggel - Editor about 4 hours ago

These are the largest known megaripples on Earth.



(Image credit: iStock / Getty Images Plus)

Ancient "megaripples" as tall as five-story buildings are hiding deep under Louisiana, and their unique geology indicates that they formed in the immediate aftermath of the asteroid strike that killed the nonavian dinosaurs, a new study finds.

The 52-foot-tall (16 meters) megaripples are about 5,000 feet (1,500 m) under the Iatt Lake area, in north central Louisiana, and date to the end of the Cretaceous period 66 million years ago, when that part of the state was underwater, the researchers said. The megaripples' size and orientation suggest that they formed after the giant space rock, known as the Chicxulub asteroid, slammed into the Yucatán Peninsula, leading to the Chicxulub impact tsunami, whose waves then rushed into shallower waters and created the megaripple marks on the seafloor, the researchers said.

The occurrence of "ripples of that size means something very big had to disturb the water column," study lead researcher Gary Kinsland, a professor in the School of Geosciences at the University of Louisiana at Lafayette, told Live Science. "This is just further evidence that the Chicxulub impact ended the Cretaceous period."

The project began when the energy corporation Devon Energy took a 3D seismic survey of Iatt Lake. A seismic survey entails creating loud sound waves (often made with "explosives or big thumps," Kinsland said) and placing surface detectors around the area that can capture the returning sound waves, which are reflected when they hit various underground rock layers. Data from these sound waves allow researchers to make maps of the underground geology.

More:
https://www.livescience.com/megaripples-tsunami-dinosaur-asteroid.html?utm_source=notification

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52-foot-tall 'megaripples' from dinosaur-killing asteroid are hiding under Louisiana (Original Post) Judi Lynn Jul 2021 OP
I have a hypothesis about this geological event. Cracklin Charlie Jul 2021 #1
Thank you so very much. This is utterly fascinating. niyad Jul 2021 #2
Sweet Lord Almighty... The Unmitigated Gall Jul 2021 #3
MegaRipple was my finishing move when I was a pro wrestler. nt Javaman Jul 2021 #4
I thought it was MagaNipple. ret5hd Jul 2021 #5
I stand corrected! LOL nt Javaman Jul 2021 #7
This message was self-deleted by its author COL Mustard Jul 2021 #10
I thought a MegaRipple was the jumbo-sized version of Fred Sanford's favorite drink. LudwigPastorius Jul 2021 #6
I Bow To Your Clearly Superior Sense Of Humor COL Mustard Jul 2021 #11
Great minds...etc. LudwigPastorius Jul 2021 #13
Either I'm In Great Company COL Mustard Jul 2021 #14
Ah yes. Unknown Beatle Jul 2021 #18
Another hippy-dippy potable: LudwigPastorius Jul 2021 #19
My dinosaur-loving grandkids locks Jul 2021 #8
Dinosaurs have been on this earth more recently than 66 million years ago FakeNoose Jul 2021 #9
I used to see a lot of dinos back in the 70s. LudwigPastorius Jul 2021 #12
Dinosaurs Old Okie Jul 2021 #15
Dinosaurs still exist in the GOP RainCaster Jul 2021 #16
Ten thousand years ago StClone Jul 2021 #17
Oh, great. Now all the "Jazz is for dinosaurs" people Pinback Jul 2021 #20

Cracklin Charlie

(12,904 posts)
1. I have a hypothesis about this geological event.
Tue Jul 20, 2021, 10:21 PM
Jul 2021

Haven’t read this yet. Can’t wait to see how this matches up.

The Unmitigated Gall

(3,804 posts)
3. Sweet Lord Almighty...
Wed Jul 21, 2021, 11:16 AM
Jul 2021

What that day must have looked like. Kind a hard not to wax biblical. I read somewhere once that they did an experiment and found that temperatures in burrows five or more feet deep remained tolerable for our little mammal forebears while absolute hellfire swept the ground above and made charcoal of the creatures that hunted and ate them.

Response to Javaman (Reply #4)

FakeNoose

(32,634 posts)
9. Dinosaurs have been on this earth more recently than 66 million years ago
Sat Jul 24, 2021, 05:51 PM
Jul 2021

If those dinos were killed off that long ago, then more came later. Because we have bone remnants from as recently as 1 million years ago. It seems evolution has been around the block a few times.

Old Okie

(142 posts)
15. Dinosaurs
Mon Jul 26, 2021, 11:18 AM
Jul 2021

After a google search for last dinosaur alive, found a Yale News article giving the age of the last dinosaur as 65 million years ago. Any source for the dinosaurs as recent as 1 million years ago?

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