Posted on 04/04/2019 8:16:25 AM PDT by centurion316
The most immediate effects of the terminal-Cretaceous Chicxulub impact, essential to understanding the global-scale environmental and biotic collapses that mark the CretaceousPaleogene extinction, are poorly resolved despite extensive previous work. Here, we help to resolve this by describing a rapidly emplaced, high-energy onshore surge deposit from the terrestrial Hell Creek Formation in Montana. Associated ejecta and a cap of iridium-rich impactite reveal that its emplacement coincided with the Chicxulub event. Acipenseriform fish, densely packed in the deposit, contain ejecta spherules in their gills and were buried by an inland-directed surge that inundated a deeply incised river channel before accretion of the fine-grained impactite. Although this deposit displays all of the physical characteristics of a tsunami runup, the timing (<1 hour postimpact) is instead consistent with the arrival of strong seismic waves from the magnitude Mw ∼10 to 11 earthquake generated by the Chicxulub impact, identifying a seismically coupled seiche inundation as the likely cause. Our findings present high-resolution chronology of the immediate aftereffects of the Chicxulub impact event in the Western Interior, and report an impact-triggered onshore mix of marine and terrestrial sedimentationpotentially a significant advancement for eventually resolving both the complex dynamics of debris ejection and the full nature and extent of biotic disruptions that took place in the first moments postimpact.
(Excerpt) Read more at pnas.org ...
http://www.freerepublic.com/focus/f-chat/3738988/posts
The best popular press account comes from the New Yorker that can be found here:
https://www.newyorker.com/magazine/2019/04/08/the-day-the-dinosaurs-died
For those who want to read the scientific paper, this is the place to go. It is long and detailed but most of it is easily understood by amateurs and those interested in paleontology.
The principle researcher, Robert DePalma is making quite a stir and the long knives in the bone digger crowd are out in full cry. You see, he doesn't have his PhD yet and he doesn't have the proper appointment in an accepted research center. In other words, he is an outsider. If fact he has been to known to have sold some of his finds and of course, this find, is potentially the biggest in the history of the discipline has a few upset. The cat fights have just begun.
With news like this, we can all take tomorrow off.
Ping.
L
Well, duh!........................
I notice there is no mention of dinosaurs in this article so it may be better received.
That’s an issue because there is very little evidence for dinosaurs within 100,000 years of the asteroid impact time.
Reading this gives me insight to where Frank Herbert got his naming ideas for Dune...
There are no mentions of dinosaurs in the published paper. In the New Yorker article, DePalma says that he has found dinosaur fossils in the same sediments with tektites and iridium, including skin fossils. These finds need to be described and published in a follow on paper which he has said he will do. Those who have seen the site and have seen many of the finds estimate that it will take at least 50 years to research the site and there is more that has yet to be discovered.
The inhabitants should have saved themselves by adopting the green new deal...
If you are a classic Doctor Who fan then you will know that it was Adric who manned the out of control space ship into the Earth, killing lots of stuff.
I favored the Bond films.
I favored the Bond films.
Yeah, the girls were far better looking, but no large crater 60mya was created in Bond films. So we’re stuck with Adric or as he’s fondly remembered: Crater Boy.
It use to be 65 million years ago and the KT boundary.
BC / AD is now CE
Next they will want us to use the metric system.
Thanks Lurker. This may be related to a recent topic regarding a K-T death assemblage.
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Thanks Lurker.
If only they had signed the Paris Climate Accords, it wouldn’t have happened . . .
very interesting New Yorker article as you point out
If I have timeI may upload a couple of enhancements I did of images from the earlier article -- for a colleague who is working to re-introcuce the paddlefish to a Texas waterway drainage and lake...
TXnMA
For those who like pictures or have grandchildren interested in this kind of thing, the link below has some nice graphics.
https://news.berkeley.edu/2019/03/29/66-million-year-old-deathbed-linked-to-dinosaur-killing-meteor/
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