At high geomagnetic latitudes, the carbon-14 spreads evenly throughout the atmosphere and reacts with oxygen to form carbon dioxide.Carbon dioxide also permeates the oceans, dissolving in the water. One of the most frequent uses of radiocarbon dating is to estimate the age of organic remains from archaeological sites. Carbon dating, also known as radiocarbon dating, is a method of estimating the age of carbon-bearing materials up to 60,000 years old.Think of it like a teaspoon of cocoa mixed into a cake dough—after a while, the ‘ratio’ of cocoa to flour particles would be roughly the same no matter which part of the cake you sampled.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.By measuring the ratio of the radio isotope to non-radioactive carbon, the amount of carbon-14 decay can be worked out, thereby giving an age for the specimen in question.But that assumes that the amount of carbon-14 in the atmosphere was constant — any variation would speed up or slow down the clock.
In other words, we have a ‘clock’ which starts ticking at the moment something dies.
The technique hinges on carbon-14, a radioactive isotope of the element that, unlike other more stable forms of carbon, decays away at a steady rate.
Organisms capture a certain amount of carbon-14 from the atmosphere when they are alive.
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