L Roebuck
Technical Support
Caving
^V^ Just a caver
Posts: 2,023
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Post by L Roebuck on Sept 20, 2008 10:09:44 GMT -5
Tucson geologists dispute study dating Grand Canyon to 17M years agoTucson Citizen " Radioactive dating of mineral deposits shows caves in and around the canyon dried out as long ago as 17 million years, when canyon cutting pulled down the water table, Polyak, Carol Hill and Yemane Asmerom wrote in Science.
But only two of the 10 caves analyzed by the New Mexico scientists showed ages beyond the widely accepted 5 million to 6 million years, and both are miles from the canyon proper. Though the caves were likely dried out at the times the study showed, it was not because the Grand Canyon was emerging, the Arizona scientists said in a technical comment published Friday in Science. " Full Article
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