1. Corrigendum to “Isotopic fractionation accompanying CO2 hydroxylation and carbonate precipitation from high pH waters at the Cedars, California, USA” [Geochim. Cosmochim. Acta 301 (2021) 91–115]
- Author
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Christensen, John N, Watkins, James M, Devriendt, Laurent S, DePaolo, Donald J, Conrad, Mark E, Voltolini, Marco, Yang, Wenbo, and Dong, Wenming
- Subjects
Earth Sciences ,Geochemistry ,Geology ,Physical Geography and Environmental Geoscience ,Geochemistry & Geophysics - Abstract
The authors regret that in the original article, the kinetic fractionation factors (KFFs) related to the CO2 hydroxylation reaction (CO2(aq) + OH– → HCO3–) were calculated using atmospheric δ18OCO2 values of 0.0 ± 0.5 ‰ (VPDB) while the correct values are 10.25 ± 0.5 ‰ (VPDB). We erroneously employed the atmospheric δ18OCO2 values from the NOAA CO2 global network (Trolier et al., 1996) by not converting atmospheric δ18OCO2 from the VPDB-CO2 scale to the VPDB scale through the following expression (e.g. Srivastava and Verkouteren, 2018): [Formula presented] This correction affects the reported oxygen isotope KFFs for CO2 hydroxylation to form HCO3– prior to CaCO3 precipitation. We have corrected Table 7 and Fig. 13 accordingly (see below). The composition of atmospheric CO2 was also incorrectly plotted on the VPDB scale in Figs. 1, 8 and 15 of our original manuscript based on previous works (Fig. 8 in Clark and Fontes, 1990; Fig. 2 in Clark et al., 1992). Importantly, the modelling outputs and main conclusions of the original article are not affected by these corrections. Nevertheless, the updated KFFs resolve an apparent discrepancy between the laboratory and field studies in our original article. Moreover, the oxygen isotope KFF for CO2 hydroxylation now displays a positive temperature dependence over the 4–28 °C range, which was not statistically significant in the original article (Fig. 13c, r2 = 0.86, n = 10, p-value
- Published
- 2023