d17O_c()
calculates the equilibrium d18O, d17O, and D17O values of a
calcite grown at a given temperature.
Usage
d17O_c(
temp,
d18O_H2O_VSMOW,
D17O_H2O = 0,
min = "calcite",
eq18 = "Daeron19",
lambda = 0.528
)
Arguments
- temp
Calcite growth temperature (°C).
- d18O_H2O_VSMOW
Water d18O value expressed on the VSMOW scale (‰).
- D17O_H2O
D17O value of ambient water calculated using a lambda of
0.528
. Default0
.- min
Mineralogy. Options are
"calcite"
(default),"aragonite"
,apatite
,siderite
, and"dolomite"
.- eq18
Equation used to calculate the 18O/16O fractionation factor between calcite and water. Options are like in
a18_c_H2O()
. Default"Daeron19"
.- lambda
Triple oxygen isotope reference slope. Default
0.528
.
Value
Returns a data frame:
d18O value of the carbonate expressed on the VSMOW scale (‰).
d17O value of the carbonate expressed on the VSMOW scale (‰).
D17O value of the carbonate expressed on the VSMOW scale (‰).
Details
$$\theta_{A/B} = \frac{\alpha^{17}_{A/B}}{\alpha^{18}_{A/B}}$$
$$ \delta'^{17}O_{H2O,VSMOW} = \beta \times \delta'^{18}O_{H2O,VSMOW} + \gamma \textrm{ , where } \beta=0.528 \textrm{ and } \gamma = 0 $$
$$\Delta^{17}O_{CaCO3,VSMOW} = \delta'^{17}O_{CaCO3,VSMOW} - \lambda \times \delta'^{18}O_{CaCO3,VSMOW} $$
NOTE: Due to a lack of experimental and theoretical data, the theta values for all carbonate mineralogies - except aragonite - are calculated with the calcite equitation from Guo & Zhou (2019):
$$\theta_{aragonite/water} = \frac{78.1173}{T^{2}} - \frac{1.5152}{T} + 0.5299$$
$$\theta_{calcite/water} = \frac{59.1047}{T^{2}} - \frac{1.4089}{T} + 0.5297$$
References
Guo, W., & Zhou, C. (2019). Triple oxygen isotope fractionation in the DIC-H2O-CO2 system: A numerical framework and its implications. Geochimica et Cosmochimica Acta, 246, 541-564. doi:10.1016/j.gca.2018.11.018
Examples
d17O_c(temp = 10, d18O_H2O_VSMOW = -1) # Returns the data frame (length = 3)
#> d18O_c d17O_c D17O_c
#> 1 32.43637 16.91235 -0.08357564
prime(d17O_c(temp = 10, d18O_H2O_VSMOW = -1)[, 2]) # Returns the d'17O value
#> [1] 16.77093
d17O_c(temp = 10, d18O_H2O_VSMOW = -1)[, 3] # Returns the D17O value
#> [1] -0.08357564