Define radioactive dating
Today, the radiocarbon-14 dating method is used extensively in environmental sciences and in human sciences such as archaeology and anthropology.
It also has some applications in geology; its importance in dating organic materials cannot be underestimated enough.
Increasingly though, students are learning about the principles of radiocarbon dates in archaeology, palaeontology and climate science degrees and can combine cross-disciplinary studies.
The method developed in the 1940's and was a ground-breaking piece of research that would change dating methods forever. Libby calculated the rate of radioactive decay of the C isotope (4) in carbon black powder.
It is oxidised quickly and absorbed in great quantities by all living organisms - animal and plant, land and ocean dwelling alike.
The next big step in the radiocarbon dating method would be Accelerated Mass Spectrometry which was developed in the late 1980s and published its first results in 1994 (3).
The other method is “Relative Dating” which gives an order of events without giving an exact age (1): typically artefact typology or the study of the sequence of the evolution of fossils.
There are three carbon isotopes that occur as part of the Earth's natural processes; these are carbon-12, carbon-13 and carbon-14.
As previously mentioned, the half life of the C isotope is 5,730 years - this means that it takes 5,730 years to reach half the radioactivity that the organism had at the point of death, another 5,730 years to reach 25% radioactivity it had at the point of death and so on.
Radiocarbon dating is simply a measure of the level of C isotopes in the atmosphere can vary.