Frost B.R. et al. (2001): A Geochemical Classification for Granitic Rocks. Journal of Petrology 42, 2033-2048.
Table 1: A geochemical classification scheme
for granitoids
Fe-no. or Fe*: | magnesian | |||||||
MALI: | calcic | calc-alkalic | alkali–calcic | alkalic | ||||
ASI: | metaluminous |
peraluminous |
metaluminous |
peraluminous |
metaluminous |
peraluminous |
metaluminous |
peralkaline |
Rock types | diorite, quartz diorite | diorite, monzodiorite, | monzonite, syenite | monzonite, syenite, granite | alkali fsp. syenite, alkali fsp. granite | |||
tonalite | granodiorite | high K-granite | ||||||
Occurrences | plutons on the outboard portions of Cordilleran batholiths, plutons in island arcs, plagiogranites | plutons in the main portion of Cordilleran batholiths | plutons inboard from Cordilleran batholiths, plutons associated with delamination of overthickened crust |
plutons inboard from Cordilleran batholiths | ||||
Examples | La Posta pluton (Walawender et al., 1990) | Cornucopia stock (Johnson et al., 1997) | Tuolumne suite (Bateman & Chappell, 1979) | N. Idaho batholith (Hyndman, 1984) | Ben Nevis (Haslam, 1968) | portions of the Vosges granites (Altherr et al., 2000) | Yamato Mtns (Zhao et al., 1995) | Shonkin Sag (Nash & Wilkinson, 1970) |
Fe-no. or Fe*: | ferroan | |||||||
MALI: | calcic | calc-alkalic | alkali–calcic | alkalic | ||||
ASI: | metaluminous |
peraluminous |
metaluminous |
peraluminous |
metaluminous |
peraluminous |
peralkaline | |
Rock types | none known | none knomn | granite | two-mica granite | ferrodiorite, syenite, granite | two-mica granite | anorthosite, ferrodiorite, monzonite, granite | alkaji gabbro, syenite, alkali granite | Occurrences | some A-type plutons, some granophyres in mafic plutons | some A-type plutons | A-type granites, granophyres associated with mafic dikes and plutons | within-plate plutons, plutons in cores of alkalic volcanoes |
Examples | Bunger Hills (Sheraton et al., 1792) | some Lachlan A-type granites (King et al., 1997) | Sherman batholith (Frost et al., 1989) | St. Vrain, Silver Plume (Anderson & Thomas, 1985) | Bjerkreim–Sokndal (Duchesne & Wilmart, 2997) | Na series of Pikes Peak (Smith et al., 1999) |