Ancient Meteorite Debris Found In Minn.
Forest Fire Reveals Rock Dust From Impact 1.85 Billion Years Ago In Canada
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The blast that hit Sudbury, Ontario 1.85 billion years ago created a crater more than 150 miles across, scattering rock and dust over nearly a million square miles. (www.fas.org)
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Interactive Leftovers From Outer Space! Learn about asteroids, comets and meteoroids, and map some of the greatest hits on Earth.
When the Ham Lake fire burned more than 118 square miles in northeastern Minnesota and Ontario in May, geologists had a field trip scheduled along the Gunflint Trail for the annual meeting of the Institute of Lake Superior Geology.
The fire closed access to most areas the group had planned to visit, so Minnesota Geological Survey geologist Mark Jirsa went up the trail to scout new locations.
In a spot he had never visited, with fire in three directions, Jirsa found evidence of a cataclysm that probably no one but a geologist would have noticed — debris from the Sudbury impact.
That blast created a crater more than 150 miles across, scattering rock and dust over nearly a million square miles.
"It's fairly dark rock," Jirsa said. "They look like concrete, but in this concrete you would throw pieces of rock of all sizes and shapes and in all possible orientations."
The rock includes balls the size and shape of a large taconite pellet which Jirsa believes formed in the impact's huge, hot cloud of dust, much as hailstones form in a storm cloud.
Jirsa says the Gunflint area probably was in or near a shallow sea when the meteorite stuck. He says there are indications that a huge tsunami may have ripped up the sea bottom and seashore, mixing them with rocks fallen from the sky into the concrete-appearing geological mess he found.
University of Toronto geology professor James Mungall, who has researched and written about the Sudbury meteorite for the scientific journal Nature, said the meteorite was probably traveling between 12 and 37 miles per second when it hit Earth with a force equal to several billion Hiroshima-sized atomic bombs. Temperatures soared above 10,000 degrees, 6,500 cubic miles of rock melted and the huge crater formed.
"The object was probably between 10 and 20 kilometers in diameter, and some of us think it was more likely to have been a comet than an asteroid, but there is no definitive evidence," Mungall said.
Previously, material thrown out by the meteorite's impact had been found as far from Sudbury as Hibbing. But the Hibbing materials — tiny fragments of shocked quartz and small ejecta — were found in core samples from 800 to 1,000 feet below the Earth's surface, while the Gunflint site lies exposed.
Jirsa said there's still much work to be done in the field to determine what secrets the Gunflint site holds that other sites don't.
"That's the critical thing. This is a different geological setting; it's a little farther away from the impact, the rocks are altered differently. It may reveal some secrets about the impact that other discoveries haven't yet. That's what we're hoping," Jirsa said.
"I think the excitement for the people of Minnesota is that we are one place in the world where you can see evidence of an ancient meteorite impact," said University of Minnesota geology professor emeritus Paul Weiblen, who is studying the debris. "This is the second-oldest and second-largest impact crater in the world."
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Best-selling author Mitch Albom on his first nonfiction work since "Tuesdays with Morrie."





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See all 42 CommentsAlso, I went to private school. When I was about 8 years old, I asked "If God created the world in 7 days, how can the dinosaurs have lived millions of years before us?" I was told that a 'day' could have been millions of years. The Bible was written before 'scientists' had calculated things like the earth's rotation, revolution around the sun, etc.
Most real 'Christians' are open-minded and accept that anything is possible. We are not all fanatics that try to push our beliefs on everyone else. Singingrick reminds me of the Jahovah's Witnesses that used to come knocking on my door EARLY on Sunday mornings to tell me that I was a sinner for believing something differently than them. They finally stopped after I invited them in to debate - I won. Score! I haven't heard from them in years!
I thought being Christian was loving thy neighbor.
SinginRick -- You claim everyone who has responded to your initial comment is intolerant and full of hatred. You also seem to suggest that they are against Jesus or God. From what I have read thus far it 'seems' that you have done the majority of maligning and had you not cast the first stone ... If you have something pertinent to say in regards to a very interesting article than by all means please share your thoughts, but I don't believe that this forum was intended for preaching.
NO! Dam you, take your phucking religion, jesus, god and bibull krap ELSEWHERE! you stupid idiots worhip a scheming murdering wicked piece of garbage and then come here and foist this religious krap off on the rest of us, this is a SCIENCE article not Sunday school- GET OUT and take your dam cross and jezus with you! Some of us have grown up past Santa Claus, jesus and the tooth fairy, it's time YOU DO TOO or produce this jesus on TV in person, or on live stage and PROVE it exists.
s'ick, put your pants on & get some air.
None of this has any business being attached to a science article.
I like the way you think. You are not an atheist. You understand that the Creator just might be clever enough to create a dynamic universe...a universe capable of evolving.
The belief that God created the lion to lay beside the lamb (and not have lunch) is reading a metaphor and taking it "as gospel." Hence the term "as gospel." True Believers see the scriptures alone. They don't understand that Christ spoke in parables and maybe, just maybe, the Old Testament is a parable.
They refuse to use the powers of observation given to us by our creator. So rick will *** science and keep his faith in Christ.
Some of us have both.
Science is just so foolish. To think that beings created by God could have enough intelligence to figure anything for themselves.
As for old sing-rick he should just keep singing because no one has ever implied that men evolved from monkeys other than anti-darwinites and igits. It's more likely that we ascended from rat like creatures and maybe a fish or two. Our body has almost the exact same elements by weight as sea water so it's likely we came from the sea in some form in our god-given distant past. Some of you should take the time to read the oldest testment - the stories our planet and the cosmos can tell us rather than some greed driven poltically motivated history "lesson" extracted from oen religion's good book.
Thank's for the offer rick. Not necessary to post your e-mail however.
"Miracle of birth" - Does that include the births of all animals are now miracles? I thought it was just reproduction.
"The mere fact that this planet is floating in the middle of outer space and can contain life is a miracle."
The earth was made as lot's of space dust came together over a very long time, attracted by the force of gravity. Since this dust was swirling around a bit as it came together to make the earth, the earth ended up spinning, and the rest is history. When something is spinning it has a property we call angular momentum. The angular momentum of an object can not change unless outside forces are exerting twists on it.
Well, I guess if I listened and had faith in what you say about miricles Rick, I wouldn't need those *** scientists and their explainations.
Or the history channel with the show universe last night. Great show bye the way.
Who is Jesus to you anyhow? Just a nice guy who taught good morals?
A murder victim, because of religious followers, teachers and the power elite.
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