A hollow bone impact caused a depression where rivers flow today, in a place known as the Pacific Gulf in the eastern United States. It turns out that she melted everything, but did not harm the bacteria that were inside the rocks just below the crater
About thirty million years after the extinction of 90% of the most common species on Earth, including the dinosaurs and marine reptiles, they faced another extinction due to an asteroid impact near the Pacific Gulf. The impact crater was recently examined for the first time, and they show that life was flexible enough to overcome the disaster.
The impact crater is currently buried under 120-350 meters of sand, silt and clay. Its area is twice the area of the island of Manhattan. The large valley that was created helped create what we now call the Pacific Gulf, which stretches across the states of Maryland and Virginia, not far from the capital, Washington. The American Geological Service (USGS) reports that about ten thousand years ago the ice layers began to melt and the river valley that was dry before was filled with water. The rivers of the Pacific region flowed directly over the buried crater.
The asteroid or comet, which is estimated to be 2-3 kilometers in diameter, is moving at tens of kilometers per minute, says Greg Gohan, director of the Pacific Gulf Impact Crater Project at the US Geological Survey. It created a crater about 85 kilometers wide and a bedrock crack about 2 kilometers deep. Today these rocks affect groundwater flow in southeastern Virginia.
Gohan and his colleagues analyzed samples from two holes drilled into the ground into the crater, near its center. "I believe that we wanted to dig into the central part of the crater and get as long a core as possible to understand the processes that caused the layers to be in the order in which we found them. Within seconds of hitting the bone, the rocks were thrown into the air. The force of the impact carved a large cavity and caused heat to rise, turning brittle rocks into a toffee-like mass. After that the material that was on the rim of the crater fell inward into the bowl-like crater as in an avalanche.
The scientists discovered that bacteria of the type common today were also found at a great depth under the crater, in old layers, and the conclusion is that they managed to survive the event, and after the ground cooled, they returned and filled every possible crevasse of dirt. Understanding the biological impact of an asteroid impact sheds light on the potential for life below the surface during the Archean period, which spanned from 3.8 billion years ago to 2.5 billion years ago when impacts from the sky were more common than today. The results also have implications for the prospect of finding life in the deep Martian biosphere. The consensus today is that if microscopic life exists on Mars it is below the surface.
The project, detailed in the June 27 issue of the journal Science, was funded by the US Geological Survey, NASA, the National Science Foundation, the Austrian Science Foundation and DOSECC.
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I agree with Ami Bachar's analysis July 1, 2008 at 12:41 pm.
Most likely the speed of the asteroid was several tens of kilometers per second (this is the speed of asteroids that hit the Earth)
Regarding the sentence "...they faced further extinction due to an asteroid impact near the Pacific Gulf", it was also written without any logical basis. The reason - the asteroid that destroyed the dinosaurs 65 million years ago was five times larger in diameter, meaning it was more than a hundred times larger in mass.
In short, the article is full of speculations that are unacceptable to the average knowledgeable reader.
Good Day
Sabdarmish Yehuda
Thanks to my father for the correction!!!
Hanan
Hanan and Avi Bilizovsky,
I suggest you read carefully what Avi Bilizovsky wrote in the first sentence of the article:
"About thirty million years after the extinction of 90% of the most common species on Earth, including the dinosaurs and marine reptiles, they faced another extinction due to an asteroid impact near the Pacific Gulf."
If so, the extinction of 90% of the species that included the dinosaurs and marine reptiles was about 65 million years ago. 30 million years later was about 30 million years ago (give or take a few million years, as I wrote in my first message). Everything is in Hebrew. This collision was about 30 million years ago, about thirty million years after the extinction of the dinosaurs.
I agree with Hanan who says that he does not think that the experiment can link bacteria today to an event that occurred millions of years ago. It certainly seems strange and downright unbelievable, for reasons I mentioned in a previous post.
Avi,
Both the definitions of bacterial species and their existence (even in our time, let alone in past times) are very problematic to the point of impossible. In most cases, bacteria cannot be identified even if they are alive and on the palm of the hand. It is clearly impossible to identify bacteria that have undergone decay processes and left only traces of fossils. Fossils show form. Find a small circle or filament and say it's a bacterium. It may resemble something today, but bacteria have several basic forms and they are all similar in shape. I reject your statement that they found species that were before and after. It is not possible and impossible.
Greetings friends,
Ami Bachar
Hanan, it's not about the extinction of the dinosaurs 65 years ago, where it was a few thousand kilometers south of there - in the Yucatan, it's about a minor local extinction
To my people, they found bacteria of the same species, and that those species were common before and after the event.
1. It seems to me that the extinction of the dinosaurs was more than 60 million years ago and not 30 million.
2. Does the asteroid move at a speed of tens of kilometers per minute, it is a very slow speed. Is it possible that there was a mistake?
I don't think the experiment can link bacteria today to an event that happened millions of years ago, but bacteria as bacteria show us how much living things are able to develop resistance. Bacterial spores can withstand no less extreme conditions and can probably survive in the vacuum and radiation of space.
Hanan Sabat
http://WWW.EURA.ORG.IL
I do not accept the explanation or rather the hypothesis that the bacteria survived the direct hit. It could be that this is indeed what happened, but it cannot be determined based on finding bacteria in that place.
First, in such a direct impact the temperatures are probably so high that they dissolve any organic material. So whoever was in the heat zone must have evaporated at that moment. There is a boundary layer, somewhere deep enough, where the temperatures were cold enough to allow life inventions and from there certain microorganisms that could handle the pressure and heat survived. Second, at the same time, thirty million years later (about today, give or take a few million years) is a very long time for bacteria to repopulate a completely abandoned area. The rate of growth and migration of bacteria from one place to another is very great, and even if no bacteria had survived the initial contact of the asteroid, after such a long time, it is expected that bacteria will be found for the first time.
Greetings friends,
Ami Bachar
About thirty million years after the extinction of 90% of the most common species on Earth
When was the injury?