zrSaturationGervasoni {GCDkit} | R Documentation |
Calculates zircon saturation temperatures for the magma of the given major-element composition and Zr concentration. Alternatively, this function returns Zr saturation levels for the assumed magma temperature.
zrSaturation.Gervasoni(WR, T = 0, Zr = filterOut(WR, "Zr", 1))
WR |
numeric matrix; whole-rock data in wt. % |
T |
assumed magma temperature in °C (single value) |
Zr |
(optional) numeric vector with Zr contents in ppm |
Calculates Zr saturation concentration for the magma of the specified major-element composition, at assumed temperature.
Given 'T
' is the estimated temperature (°C) of the magma, the Zr saturation level
is given by equation of Gervasoni et al. (2016):
Zr.sat = exp(4.29-1.35*log(G)+0.0056*T)
where
G = (3*Al2O3 + SiO2)/(Na2O + K2O + CaO + MgO + FeO)
On the other hand, the saturation temperature (°C) can be obtained from the observed Zr concentration and magma composition expressed by the Λ parameter (assuming no zircon inheritance):
TZr.sat.C = (ln(Zr)-4.29+1.35*ln(G))/0.0056
Returns a matrix 'results
' with the following columns:
Zr.obs |
observed Zr concentrations in ppm |
G |
G value |
Zr.sat.G16 |
saturation levels of Zr (ppm) for assumed T |
TZr.sat.C.G16 |
zircon saturation temperatures in °C |
Saturation.r
Vojtěch Janoušek, vojtech.janousek@geology.cz
Gervasoni F, Klemme S, Rocha-Júnior ERV, Berndt J (2016) Zircon saturation in silicate melts: a new and improved model for aluminous and alkaline melts. Contrib Mineral Petrol 171:21 doi: 10.1007/s00410-016-1227-y
Scaillet B, MacDonald R (2001) Phase relations of peralkaline silicic magmas and petrogenetic implications. J Petrol 42:825-845. doi: 10.1093/petrology/42.4.825
sampleDataset("sazava") zrSaturation.Gervasoni(WR,T=800) # Example from Scaillet & MacDonald (2001) # mentioned by Gervasoni et al.(2016) z <- c(75.20,0.17,12.11,1.81,0.04,0.07,0.44,4.59,4.73,439) names(z) <- c("SiO2","TiO2","Al2O3","FeOt","MnO","MgO","CaO","Na2O","K2O","Zr") zrSaturation.Gervasoni(z,T=693)