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Name: Bason
Status: student
Grade: 9-12
Location:  TX
Country: N/A
Date: May 2006

Question:
Evolutionist say that they can date a fossil by the rock that its in and they can date the rock by the fossil. How can they do this?



Replies:
That is not actually accurate. First off, it is not just "evolutionists" that say that one can with reasonable accurately predict the age of a fossil...almost any reputable geologist, physicist, biologist, or chemist would agree. It depends on the age of the fossil...or for that matter biological sample. Carbon dating goes like this...

Carbon 14 is produced when nitrogen 14 is bombarded by cosmic rays in the upper atmosphere. The Carbon 14 makes its way throughout the atmosphere is absorbed from the air by plants through photosynthesis. When animals eat the plants they incorporate the C14 into their tissues. When an organism dies, it stops incorporating C14. The C14 that is already in the organism decays at a constant rate. Carbon 14 decays at a steady rate and changing to nitrogen 14. The half life of carbon 14 is 5730 years. In 5730 years half of the Carbon 14 that was in the organism when it died will have decayed into nitrogen 14. After about 50,000 years, the amount of C14 remaining will be so small that the fossil can't be dated reliably. Scientists are distrustful of their own measurements, so they like it when they can at the same time have some other system to ensure they are accurate. One of the most common ways scientists make sure of the accuracy of carbon dating is with tree rings. Another is with historical records. These only go so far back in history. For dating of samples older than 40-50 thousand years we use other isotopes but it is more complicated but still backed up in a variety of ways so that almost any reasonable person would believe it.

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