Jung {GCDkit} | R Documentation |
This function estimates the temperature of a granitic magma based on measured Al2O3/TiO2 ratio and experimental constraints. The regression formulae were defined by Jung & Pfänder (2007).
Jung(model = NULL, plot = TRUE)
model |
specification of the model |
plot |
logical; should be shown a Al2O3/TiO2 vs. CaO/Na2O plot? |
As shown by Sylvester (1998), the Al2O3/TiO2 ratio in the granitic magmas is temperature sensitive, decreasing with the increasing temperature of the crustal anatexis. This probably reflects an increasing instability of Ti-bearing phases with progressive crustal fusion.
Jung & Pfänder (2007) compiled the available experimental data and defined a set of regression formulae (linear, power law and exponential) for several types of protoliths.
Any of the following models can be chosen: pelite melting, psammite melting, igneous rock melting, A-type granite melting, amphibolite melting after Rapp & Watson (1995) and amphibolite melting after Patińo Douce & Beard (1995).
Optionally, also Al2O3/TiO2 vs. CaO/Na2O plot could be displayed with three secondary axes annotated by the calculated temperatures.
Returns a matrix 'results
' with the following columns:
Al2O3/TiO2 |
wt. % ratio of Al2O3/TiO2 |
T_Al/Ti.power.C |
temperature in C, power law calibration |
T_Al/Ti.exp.C |
temperature in C, exponential calibration |
T_Al/Ti.linear.C |
temperature in C, linear calibration |
T_Al/Ti.mean.C |
mean temperature in C, based on the above three models |
Jung.r
As pointed out by S. Jung (pers. com. 2009), in Table 1 of their original paper were printed wrongly several of the regression coefficients. These are:
Rock | Model | Jung and Pfänder (2007) | Corrected |
A-type | power law | B = 0.992 | B = 9.921 |
amphibolite (Rapp and Watson 1995) | power law | A = 2.82x10^3 | A = 2.82x10^30 |
The function implements these corrected values.
Vojtěch Janoušek, vojtech.janousek@geology.cz
Jung S, Pfänder JA (2007) Source composition and melting temperatures of orogenic granitoids: constraints from CaO/Na2O, Al2O3/TiO2 and accessory mineral saturation thermometry. Eur J Mineral 19: 859-870 doi: 10.1127/0935-1221/2007/0019-1774
Patińo Douce AE, Beard JS (1995) Dehydration-melting of biotite gneiss and quartz amphibolite from 3 to 15 kbar. J Petrol 36: 707-738 doi: 10.1093/petrology/36.3.707
Rapp RP, Watson EB (1995) Dehydration melting of metabasalt at 8-32 kbar: implications for continental growth and crust-mantle recycling. J Petrol 36: 891-931 doi: 10.1093/petrology/36.4.891
Sylvester PJ (1998) Post-collisional strongly peraluminous granites. Lithos 45: 29-44 doi: 10.1016/S0024-4937(98)00024-3
data(sazava) accessVar("sazava") Jung("A-type") Jung("psammite",plot=FALSE)