Debon {GCDkit} | R Documentation |
Assigns data for Debon & Le Fort's B-A and P-Q diagrams into Figaro template (list 'sheet
') and appropriate values into 'x.data
' and 'y.data
'.
DebonBA() DebonPQ()
The B-A diagram as proposed by Debon and Le Fort (1983) defines six sectors (I - VI), reflecting alumina balance of samples. Following minerals are characteristic for individual sectors:
I | Peraluminous domain | muscovite > biotite |
II | biotite > muscovite |
|
III | biotite (+- minor amphibole) |
|
IV | Metaluminous domain | biotite, amphibole, +- pyroxene |
V | clinopyroxene, +- amphibole, +-biotite |
|
VI | unusual mineral associations (carbonatites ... ) |
Layout of the P-Q diagram of the same authors corresponds to cationic proportions of quartz, K-feldspar and plagioclase. Acronyms used as classification output represent following rocks groups:
label | plutonic rocks | volcanic rocks |
go | gabbro, diorite, anorthosite | basalt, andesite, kenningite |
mzgo | monzogabbro, monzodiorite | latibasalt, latiandesite |
mz | monzonite | latite |
s | syenite | trachyte |
dq | qtz diorite,qtz gabbro,qtz anorthosite | qtz andesite,qtz basalt |
mzdq | qtz monzodiorite,qtz monzogabbro | qtz latiandesite,qtz latibasalt |
mzq | quartz monzonite | quartz latite |
sq | quartz syenite | quartz trachyte |
to | tonalite, trondhjemite | dacite |
gd | granodiorite, granogabbro | rhyodacite |
ad | adamellite | dellenite |
gr | granite | rhyolite |
Parameters for the diagram are calculated by the function 'DebonCalc
'.
All of them are based on millications (1000 gram-atoms per 100 grams).
P = K - (Na + Ca)
Q = Si / 3 - (K + Na + 2 * Ca / 3)
A = Al - (K + Na + 2 Ca)
B = Fe + Mg + Ti
Note that the diagrams B-A and P-Q are recommended as complementary, i.e. resulting names should be used in conjunction (granite II etc.). For details, see Debon & Le Fort (1983) or (1988).
sheet |
list with Figaro Style Sheet data |
x.data |
P or B value. See details. |
y.data |
Q or A value. See details. |
Vojtech Erban, vojtech.erban@geology.cz
& Vojtech Janousek, vojtech.janousek@geology.cz
Debon F & Le Fort P (1983) A chemical-mineralogical classification of common plutonic rocks and associations. Trans Roy Soc Edinb; Earth Sci 73: 135-149
Debon F & Le Fort P (1988) A cationic classification of common plutonic rocks and their magmatic associations: principles, method, applications. Bull. Mineral 111: 493-511
classify figaro plotDiagram DebonCalc