Environmental Studies

A Dictionary of Ecology A Dictionary of Earth Sciences Further reading

carbon isotopes

A Dictionary of Ecology | 2004 | | Copyright

carbon isotopes The naturally occurring isotopes of carbon, of which there are three: ¹²C making up about 98.9 per cent; ¹³C about 1.1 per cent; and ¹⁴C whose amount is negligible, but which is detectable because it is radioactive. The relative abundance of these isotopes varies and the study of this variation is an important tool in geologic research, especially radiometric dating. Carbon-isotope dating is a method of radiometric age-dating using the amount of the heavy, radioactive isotope carbon-14 remaining in organic matter. Carbon-14 has a half-life of 5730 ± 40 years and the amount of the isotope present can be used to date materials up to about 50 000 years old (see radiocarbon dating). Measurement of the ratio of carbon-13 to carbon-12 allows the recognition of carbonate precipitated from a variety of different sources.

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MICHAEL ALLABY. "carbon isotopes." A Dictionary of Ecology. 2004. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>.

MICHAEL ALLABY. "carbon isotopes." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O14-carbonisotopes.html

MICHAEL ALLABY. "carbon isotopes." A Dictionary of Ecology. 2004. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-carbonisotopes.html

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carbon isotopes

A Dictionary of Earth Sciences | 1999 | | Copyright

carbon isotopes Natural carbon is composed of three isotopes: ¹²C making up about 98.9%; ¹³C about 1.1%; and ¹⁴C whose amount is negligible, but which is detectable because it is radioactive. The relative abundance of these isotopes varies and the study of this variation is an important tool in geologic research, especially radiometric dating. Carbon-isotope dating is a method of radiometric age-dating using the amount of the heavy, radioactive isotope carbon-14 remaining in organic matter. Carbon-14 has a half-life of 5730 ± 40 years and the amount of the isotope present can be used to date materials up to about 50 000 years old (see RADIOCARBON DATING). In diagenetic studies (see DIAGENESIS), measurement of the ratio of carbon-13 to carbon-12 allows the recognition of carbonate precipitated from a variety of different sources.

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AILSA ALLABY and MICHAEL ALLABY. "carbon isotopes." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>.

AILSA ALLABY and MICHAEL ALLABY. "carbon isotopes." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O13-carbonisotopes.html

AILSA ALLABY and MICHAEL ALLABY. "carbon isotopes." A Dictionary of Earth Sciences. 1999. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-carbonisotopes.html

Learn more about citation styles

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