Phosphoric acid fractionation factors for calcite and aragonite between 25 and 75 °C: Revisited

  title={Phosphoric acid fractionation factors for calcite and aragonite between 25 and 75 °C: Revisited},
  author={Sang-Tae Kim and A. Mucci and B. Taylor},
  journal={Chemical Geology},
This paper reports the results of an investigation to re-determine the phosphoric acid fractionation factor for calcite and aragonite in order to improve the accuracy and limit the uncertainty of this very important quantity. The 18 O/ 16 O ratio of 100% of the oxygen in calcite and aragonite was determined directly by combining data from a two-step procedure involving thermal decomposition of the carbonate, followed by fluorination of the residual CaO using BrF5. The oxygen isotope composition… Expand

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