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How do you tell the age of a fossil?
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English - April 16, 2020 04:00 - 5 minutes - 2.35 MB - ★★★★★ - 12 ratingsNews news adirondacks north country public radio Homepage Download Apple Podcasts Google Podcasts Overcast Castro Pocket Casts RSS feed
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(Apr 16, 2020) Unlike organic material, which can be dated using carbon-14, stone and fossils often contain no carbon, or may be older than the carbon method can track. Radioactive potassium dating measures the ratio between a radioactive variety of potassium and the substance it breaks down into, argon gas. That can age material back billions of years. One problem: you need the gas to have been trapped in bubbles of volcanic ash.
Martha Foley and Curt Stager discuss the problems of reading the geological clock.