Bicarbonate, carbon-14 dating

Fractionation and Contamination. The ratio 14C/12C in certain materials may be affected by isotopic fractionation. For example, the uptake of carbon dioxide and its incorporation into plant tissue may be accompanied by substantial fractionation that depends on the plant species. With marine organisms, fractionation may also be important, especially when inorganic carbonate and bicarbonate are involved. Corrections for fractionation must be made for precise radiocarbon dating. 

Table 4. Carbon-14 dating analyses for fulvic acid and bicarbonate...

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