isogeochem (version 1.1.1)

D48: Equilibrium carbonate D47 value

Description

D48() calculates the equilibrium carbonate D48 value for a given temperature.

Usage

D48(temp, eq)

Value

Returns the carbonate equilibrium D48 value expressed on the CDES90 scale (‰).

Arguments

temp

Carbonate growth temperature (°C).

eq

Equation used for the calculation.

• "Fiebig21": the CDES90 calibration of Fiebig et al. (2021).

• "Swart21": the CDES90 "PBLM1" calibration in Swart et al. (2021).

Details

"Fiebig21":

$$\Delta_{48, CDES90} = 1.028 \times (6.002 \times \frac{1}{T} - 1.299 \times \frac{10^{4}}{T^{2}} + 8.996 \times \frac{10^{6}}{T^{3}} - 7.423 \times \frac{10^{8}}{T^{4}}) + 0.1245$$

"Swart21":

$$\Delta_{48, CDES90} = 0.0142 \times \frac{10^{6}}{T^{2}} + 0.088$$

References

Bajnai, D., Guo, W., Spötl, C., Coplen, T. B., Methner, K., Löffler, N., et al. (2020). Dual clumped isotope thermometry resolves kinetic biases in carbonate formation temperatures. Nature Communications, 11, 4005. tools:::Rd_expr_doi("10.1038/s41467-020-17501-0")

Fiebig, J., Daëron, M., Bernecker, M., Guo, W., Schneider, G., Boch, R., et al. (2021). Calibration of the dual clumped isotope thermometer for carbonates. Geochimica et Cosmochimica Acta. tools:::Rd_expr_doi("10.1016/j.gca.2021.07.012")

Swart, P. K., Lu, C., Moore, E., Smith, M., Murray, S. T., & Staudigel, P. T. (2021). A calibration equation between D48 values of carbonate and temperature. Rapid Communications in Mass Spectrometry, 35(17), e9147. tools:::Rd_expr_doi("10.1002/rcm.9147")

See Also

Other equilibrium_carbonate: D47(), d17O_c(), d18O_c()

Examples

D48(temp = 33.7, eq = "Fiebig21") # Returns 0.237
D48(temp = 33.7, eq = "Swart21") # Returns 0.239