Isotopic Fractionation (Planetary Process)
The term isotope fractionation refers to subtle variations of isotopic abundances among coexisting solids, liquids, and gases. It can both take place at equilibrium and reflect kinetic effects. It can be mass dependent, when its amplitude is a monotonic function of the isotope masses, or else be mass independent. It is normally given in delta (δ) units, which represent the relative deviation of a particular isotopic ratio in a particular sample with respect to this ratio in a reference material.
American physical chemist Harold C. Urey (1947) and chemists J. Bigeleisen and M.G. Meyer (1947) must be credited for the first theoretical prediction of isotopic fractionation. J. M. McCrea (1950) calibrated the fractionation of oxygen isotopes between coexisting carbonates and liquid water.
Isotope fractionation results from slightly different chemical properties among the isotopes of the same element. These variations are large enough (typically 0.1–10 ‰, where ‰...
KeywordsIsotopic Ratio Carbon Isotope Oxygen Isotope Isotope Fractionation Vibrational Energy
References and Further Reading
- Criss RE (1999) Principles of stable isotope distribution. Oxford University Press, OxfordGoogle Scholar
- Sharp Z (2007) Principles of stable isotope geochemistry. Prentice Hall, Upper Saddle RiverGoogle Scholar
- Valley JW, Cole DR (2001) Stable isotope geochemistry, vol 43, Reviews in mineralogy and geochemistry. Mineralogical Society of America, Washington, DCGoogle Scholar