How is carbon 14 dating done
Plants and animals naturally incorporate both the abundant C-12 isotope and the much rarer radiocarbon isotope into their tissues in about the same proportions as the two occur in the atmosphere during their lifetimes.
When a creature dies, it ceases to consume more radiocarbon while the C-14 already in its body continues to decay back into nitrogen.
It is naturally unstable and so it will spontaneously decay back into N-14 after a period of time.
It takes about 5,730 years for half of a sample of radiocarbon to decay back into nitrogen.
As soon as it dies, however, the C ration gets smaller.
In other words, we have a ‘clock’ which starts ticking at the moment something dies.
This is how carbon dating works: Carbon is a naturally abundant element found in the atmosphere, in the earth, in the oceans, and in every living creature.
C-12 is by far the most common isotope, while only about one in a trillion carbon atoms is C-14.
The fact that the C doesn’t matter in a living thing—because it is constantly exchanging carbon with its surroundings, the ‘mixture’ will be the same as in the atmosphere and in all living things.It takes another 5,730 for half of the remainder to decay, and then another 5,730 for half of what's left then to decay and so on.
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