So this crater is formed by multiple meteorites, huh? Would you scientists like to try again?
Posted on 03/09/2005 10:19:19 AM PST by ZGuy
It's a mystery that has puzzled scientists for years but researchers said Wednesday they have discovered why there isn't much melted rock at the famous Meteor Crater in northern Arizona.
An iron meteorite traveling up to 12 miles per second was thought to have blasted out the huge hole measuring three-quarters of a mile across in the desert.
The impact of an object at that speed should have left large volumes of melted rock at the site. But British and American scientists said the reason it didn't was because the meteorite was traveling slower than previously estimated.
"We conclude that the fragmented iron projectile probably struck the surface at a velocity of about 12 km (7.5 miles) (per second)," said Professor H. Jay Melosh, of the University of Arizona, in a report in the science journal Nature.
Meteor Crater, which was formed about 50,000 years ago, was the first terrestrial crater identified as a meteorite impact scar.
Melosh and Gareth Collins, of Imperial College London, used a simple model to calculate the speed on impact. They showed the meteorite had slowed when it hit the Earth's atmosphere and broke into fragments before it struck the Earth.
They calculated the impact velocity was about 26,800 miles per hour.
"Even though iron is very strong, the meteorite had probably been cracked from collisions in space," Melosh said in a statement.
"The weakened pieces began to come apart and shower down from about 8.5 miles high. As they came apart, atmospheric drag slowed them down, increasing the forces that crushed them so that they crumbled and slowed more," he added.
The scientists said that at about 3 miles altitude, most of the meteorite was spread in a large cloud.
It's a matter of some fairly complex, but well tried and tested, chemical and radiological techniques.
Your average mainstream media science article isn't going to take about 10 pages filled with chemical formulas explaining how rocks and fossils are dated EVERY single time they mention some date from a scientist that annoys some idiotic Young Earth Creationist because it's older than 6,000 years.
In terms of the popular press probably the most extensive and understandable explanation of dating of rock is in the "Crossing the Craton" section of John McPhee's "Annals of the Former World."
And while you're there (Winslow), you can stay at the very nicely restored La Posada, a hotel left over from the great coast to coast railroad days. Designed by Mary Jane Coulter (no photos needed of that Coulter).
The trestle bridge over Diablo canyon is close and worth a side trip as well.
Yep, he musta been driving drunk and on his way to buy cocaine while he was AWOL from the TNG. Yep, that's it.
The suspicion that the crater is only 50,000 years old, giver or take about 3,000 years, comes from the fact that it is not terribly weathered. Anything over 100,000 years would be much more worn down or even obliterated.
Fortunately, the climate is fairly dry in that area, so the weathering influence comes mainly from the action of wind and sand, and not so much from rain, which can do much more damage to such a site.
In short, the age determination is rough, and more a process of elimination: no more than 100,000 years, and no less than 20,000 (and certainly more than 6,000 years) based on the amount of weathering and the amount of debris buildup in the bottom of the crater.
Hope this helps.
So this crater is formed by multiple meteorites, huh? Would you scientists like to try again?
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V66-48C8KYS-1FD&_user=99318&_handle=V-WA-A-W-BW-MsSAYWW-UUA-U-AAAWEDEECA-AAAUCZUDCA-EDADEWDZV-BW-U&_fmt=summary&_coverDate=09%2F30%2F1991&_rdoc=26&_orig=browse&_srch=%23toc%235806%231991%23999449990%23418848!&_cdi=5806&view=c&_acct=C000007678&_version=1&_urlVersion=0&_userid=99318&md5=aedd70e4125104f8c9860f3f12b29090
Studies like this are so pitifully stupid!
Sometimes there are no explanations for phenomenom like this.
Man, (the species) in general wants to say they understand everything in the world.
Somehow........it's just not that important.
Tax dollars are used for this group, I would imagine.(rolling my eyes)
Article wasn't that clear and I think people are misunderstanding what was said.
It wasn't a wide scattering of multiple meteorites...what they're saying is it wasn't a coherent big block when it hit; it was a grouping of pieces that were all right next to each other.
Good thing it is in the middle of nowhere. It would have been disastrous if it hit a city or something.
Yes, I am kidding.
Regardless of theories, the meteor strike blasted rock and bits of itself (nickle-iron) for miles. Owners of surrounding ranches still find pieces which they sell to rock shops. My sample weighs several ounces.
Are you for real or just trolling? Seriously.
1. It reminds me of what Mecca should look like if there's another 9-11 type attack.
2. Danny and geezer - go pick your fight on one of the evolution/creation threads.
1. Meteor craters have not been observed to happen, now or in the past.
2. Meteor craters have never been reproduced in the lab, and are thus not scientific.
3. Thomas Jefferson said: "Gentlemen, I would rather believe that two Yankee professors would lie than believe that stones fall from heaven."
4. The odds against a random rock falling from the sky, striking the earth, and making a crater are astronomical.
5. The second law of thermodynamics prohibits meteor craters.
6. Meteor craters are not mentioned in the bible, nor are "rocks from the sky."
7. Craterism is a product of materialism and a Godless, naturalistic worldview.
8. Belief that rocks can fall from the sky promotes hedonism and amoral, animalistic behavior.
9. Craterism makes no predictions and is untestable; it is therefore not scientific.
10. Craterists can produce micro-craters, but have no evidence of macro-cratering.
11. Aristotle didn't believe in Craterism. Nor did Galileo, Newton, or Einstein.
12. Einstein even said: "God does not play dice!" Are you smarter than Einstein?
13. Scientists are abandoning craterism because they know it is not supported by evidence.
14. Anyone who thinks there are rocks in the sky has rocks in his head.
15. It takes more faith to believe in Craterism than it does to believe in the Tooth Fairy.
16. More and more scientists are turning to "Intelligent Crater" theory (IC). Craterism is a theory in crisis!
A friend of mine and I drove to see this when we were both in grad school in Arizona. There is virtually nothing within miles of the place and the first comment out of our mouths when we walked up to the rim was "Wow, that is one big f***ing hole!" It is worth seeing but it doesn't impress as much some of the other scenic attractions in Arizona. When we walked up the rim of the Grand Canyon there was no comment for about a minute, obscene or otherwise, just an intake of breath.
You are kidding aren't you?
Thanks for the reply.
So it's nothing more than an educated guess. And the failure to account for a global flood and/or it's aftermath, or even a bad projection in sediment rates could cause 50,000 to be a bad date.
LOL! Nice parody.
Thank God it missed the road ;)
The article says 50,000. We have a right to question it. And the right to protest that the press never gives you the data or method of date determination to evaluate the date yourself.
The article says 50,000. We have a right to question it. And the right to protest that the press never gives you the data or method of date determination to evaluate the date yourself.
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