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Oldest known impact crater found
Cardiff University ^ | Cardiff University

Posted on 07/08/2012 11:37:26 PM PDT by rjbemsha

A 100 kilometre-wide crater has been found in Greenland, the result of a massive asteroid or comet impact a billion years before any other known collision on Earth.

(Excerpt) Read more at cardiff.ac.uk ...


TOPICS: Miscellaneous
KEYWORDS: abiogenic; catastrophism; crater; found; greenland; impact; meteorite; oldest; thomasgold
According to the article, "...around 30% of [the 180 impact craters discovered on earth] contain important natural resources of minerals or oil and gas." This one may contain a bonanza of nickel.
1 posted on 07/08/2012 11:37:37 PM PDT by rjbemsha
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To: rjbemsha

I didn’t realize Greenland had that much “old” surface. There’s not much crust left that’s over 1 billion years old.


2 posted on 07/08/2012 11:40:38 PM PDT by Little Pig (Vi Veri Veniversum Vivus Vici.)
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To: Little Pig

At least, that hasn’t been extensively remodeled at some point.


3 posted on 07/08/2012 11:41:18 PM PDT by Little Pig (Vi Veri Veniversum Vivus Vici.)
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To: Little Pig
Over the 3 billion years since the impact, the land has been eroded down to expose deeper crust 25 km below the original surface. All external parts of the impact structure have been removed, but the effects of the intense impact shock wave penetrated deep into the crust - far deeper than at any other known crater - and these remain visible.
Just... WOW!
4 posted on 07/08/2012 11:51:18 PM PDT by LibWhacker
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To: SunkenCiv

ping


5 posted on 07/09/2012 12:15:27 AM PDT by Captain Beyond (The Hammer of the gods! (Just a cool line from a Led Zep song))
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To: rjbemsha

Hey better watch out, that is where the “Thing” is, don’t thaw him out.


6 posted on 07/09/2012 12:48:45 AM PDT by itsahoot (The Political Elites are the modern Royals, and the king shall have his due.)
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To: rjbemsha
The meat of the article:
"...
The previously oldest known crater on Earth formed 2 billion years ago and the chances of finding an even older impact were thought to be, literally, astronomically low. p> Now, a team of scientists have discovered the remains of a giant 3 billion year old impact near the Maniitsoq region of West Greenland.

Finding the evidence was made all the harder because there is no obvious bowl-shaped crater left to find. Over the 3 billion years since the impact, the land has been eroded down to expose deeper crust 25 km below the original surface. All external parts of the impact structure have been removed, but the effects of the intense impact shock wave penetrated deep into the crust - far deeper than at any other known crater - and these remain visible.

However, because the effects of impact at these depths have never been observed before it has taken nearly three years of painstaking work to assemble all the key evidence. (The team was...) left with a giant impact as the only explanation for all of the facts."

Only around 180 impact craters have ever been discovered on Earth and around 30% of them contain important natural resources of minerals or oil and gas. The largest and oldest known crater prior to this study, the 300 kilometre wide Vredefort crater in South Africa, is 2 billion years in age and heavily eroded.

Dr McDonald added that "It has taken us nearly three years to convince our peers in the scientific community of this but the mining industry was far more receptive. A Canadian exploration company has been using the impact model to explore for deposits of nickel and platinum metals at Maniitsoq since the autumn of 2011."
..."

7 posted on 07/09/2012 4:09:13 AM PDT by Repeal The 17th (We have met the enemy and he is us.)
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To: rjbemsha

I thought the 450-km diameter Hudson Bay’s Nastapoka Arc crater on the East side of Hudson’s Bay was the biggest.
http://media.photobucket.com/image/hudson%2527s%20bay%20crater%20size/VolvoHeretic/Assorted%2520Stuff/CopyofHudsonBayImpactCraterDWG.jpg


8 posted on 07/09/2012 5:00:26 AM PDT by BuffaloJack (Repeal Obamacare, the CITIZENSHIP TAX)
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To: rjbemsha
...contain important natural resources of minerals or oil and gas."

Who knew?

9 posted on 07/09/2012 5:29:49 AM PDT by depressed in 06 (6 November, 2012, the day our embarrassment is sent back to Kenya.)
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To: rjbemsha
A Canadian exploration company has been using the impact model to explore for deposits of nickel and platinum metals at Maniitsoq since the autumn of 2011."

Horrible! This precious crater should be preserved for all eternity in its natural state for the enjoyment of all. Hands off the crater! Stop the mining company exploitation!

10 posted on 07/09/2012 5:44:10 AM PDT by ProtectOurFreedom
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To: rjbemsha

11 posted on 07/09/2012 6:35:19 AM PDT by Hotlanta Mike (Resurrect the House Committee on Un-American Activities (HUAC)...before there is no America!)
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To: LibWhacker

When an impact crater is 3 billion years old, does that mean that it’s too old to be Bush’s fault?


12 posted on 07/09/2012 10:20:39 AM PDT by Verginius Rufus
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To: Captain Beyond; 75thOVI; agrace; aimhigh; Alice in Wonderland; AndrewC; aragorn; aristotleman; ...
Thanks Captain Beyond.



13 posted on 07/09/2012 3:41:24 PM PDT by SunkenCiv (https://secure.freerepublic.com/donate/)
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To: rjbemsha
Older than the Bob Dole campaign, even? Must belong to Carter...or McGovern.

Cheers!

14 posted on 07/09/2012 5:23:43 PM PDT by grey_whiskers (The opinions are solely those of the author and are subject to change without notice.)
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To: Little Pig; SunkenCiv; All

Is this visible now because there has been more melting of the ice or did people just not recognize it before?


15 posted on 07/10/2012 8:53:03 PM PDT by gleeaikin
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To: gleeaikin

Used to be there were no craters on the Earth, because of erosion. IOW, no one bothered to look for them, and when they were pointed out or obvious as hell, they were characterized either as erosional features (like the Carolina Bays still are by some people) or as “cryptovolcanic” (as the Barringer Meteor Crater was). Nearly 200 have been identified, mostly large like the Manicougan structure.


16 posted on 07/11/2012 3:30:07 AM PDT by SunkenCiv (https://secure.freerepublic.com/donate/)
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