When is carbon dating used
When a creature dies, it ceases to consume more radiocarbon while the C14 already in its body continues to decay back into nitrogen.So, if we find the remains of a dead creature whose C12 to C14 ratio is half of what it's supposed to be (that is, one C14 atom for every two trillion C12 atoms instead of one in every trillion) we can assume the creature has been dead for about 5,730 years (since half of the radiocarbon is missing, it takes about 5,730 years for half of it to decay back into nitrogen).If the ratio is a quarter of what it should be (one in every four trillion) we can assume the creature has been dead for 11,460 year (two halflives).After about 10 halflives, the amount of radiocarbon left becomes too miniscule to measure and so this technique isn't useful for dating specimens which died more than 60,000 years ago.
Another limitation is that this technique can only be applied to organic material such as bone, flesh, or wood. Carbon Dating  The Premise Carbon dating is a dating technique predicated upon three things: Carbon Dating  The Controversy Carbon dating is controversial for a couple of reasons.
First of all, it's predicated upon a set of questionable assumptions.
When is carbon dating used comments 

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