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Fossil magnetism helps prove mass extinction theory
University of Bristol ^ | May 4, 2009 | Unknown

Posted on 05/05/2009 6:13:30 AM PDT by decimon

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Meteor May Have Started Dinosaur Era
by Kenneth Chang
May 17, 2002
In the layer of rock corresponding to the extinction, the scientists found elevated amounts of the rare element iridium. A precious metal belonging to the platinum group of elements, iridium is more abundant in meteorites than in rocks on Earth. A similar spike of iridium in 65 million-year-old rocks gave rise in the 1970's to the theory that a meteor caused the demise of the dinosaurs... The levels are only about one-tenth as high as those found at the later extinction. That could mean that the meteor was smaller or contained less iridium... In the same rock layer, Dr. Olsen and his colleagues found a high concentration of fern spores -- considered an indicator of a major disruption in the environment. Because spores carried by the wind can travel long distances, ferns are often the first plants to return to a devastated landscape. The scientists found more evidence of rapid extinction in a database of 10,000 muddy footprints turned to rock in former lake basins from Virginia to Nova Scotia... Because the sediment piles up quickly in lake basins, the researchers were able to assign a date to each footprint, based on the layer of rock where it was found. They determined that the mix of animals walking across what is now the East Coast of North America changed suddenly about 200 million years ago. The tracks of several major reptile groups continue almost up to the layer of rock marking the end of the Triassic geologic period 202 million years ago, then vanish in younger layers from the Jurassic period...

21 posted on 05/05/2009 6:32:43 PM PDT by SunkenCiv (https://secure.freerepublic.com/donate/____________________ Profile updated Monday, January 12, 2009)
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To: An.American.Expatriate

Gen 7:11 & thereabouts - reset button hit for sure.


22 posted on 05/05/2009 6:41:06 PM PDT by MrB (Go Galt now, Bowman later)
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To: decimon
The Doctor Fun Page

23 posted on 07/29/2009 2:43:23 PM PDT by SunkenCiv (https://secure.freerepublic.com/donate/__Since Jan 3, 2004__Profile updated Monday, January 12, 2009)
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