Converting isotope delta from VPDB to VSMOW

to_VSMOW() converts d18O value expressed on the VPDB scale to the VSMOW scale.

Usage

to_VSMOW(d18O_VPDB, eq = "IUPAC")

Arguments

d18O_VPDB

d18O values expressed on the VPDB scale (‰).

eq

Equation used for the conversion.

• "IUPAC" (default): the IUPAC recommended equation listed in Brand et al. (2014) and Kim et al. (2015).

• "Coplen83": the equation listed in Coplen et al. (1983) and the Hoefs book.

Value

Returns the d18O value expressed on the VSMOW scale (‰).

Details

The IUPAC recommended equation to convert between the scales is:

$$\delta^{18}O_{VSMOW} = 1.03092 \times \delta^{18}O_{VPDB} + 30.92$$

References

Coplen, T. B., Kendall, C., & Hopple, J. (1983). Comparison of stable isotope reference samples. Nature, 302, 236-238. doi:10.1038/302236a0

Brand, W. A., Coplen, T. B., Vogl, J., Rosner, M., & Prohaska, T. (2014). Assessment of international reference materials for isotope-ratio analysis (IUPAC Technical Report). Pure and Applied Chemistry, 86(3), 425-467. doi:10.1515/pac-2013-1023

Kim, S.-T., Coplen, T. B., & Horita, J. (2015). Normalization of stable isotope data for carbonate minerals: Implementation of IUPAC guidelines. Geochimica et Cosmochimica Acta, 158, 276-289. doi:10.1016/j.gca.2015.02.011

See also

to_VPDB() converts d18O values expressed on the VSMOW scale to the VPDB scale.

Examples

to_VSMOW(0)
#> [1] 30.92
to_VSMOW(0, eq = "Coplen83")
#> [1] 30.91