Fig.1 QAPF classification diagram based on the actual minerals of volcanic rocks[2]

Fig.2 Chemical classification and nomenclature of (Na2O+K2O)-SiO2 diagram (TAS) for volcanic rocks [4]

Fig.3 Zr/TiO2-Nb/Y diagram ((a) Distribution range of different volcanic rocks in the Winchester and Floyd’s diagram[1]; (b) A new boundary fitted based on the density boundary of the data; (c) A comparison between the boundaries in the original and improved diagram (according to ref. [5]))

Fig.4 Accuracy of rock type identification by random forest method[5] (The accuracy by Random Forest Algorithm in the last line is the result of cross-validation of Random Forest in training stage)

Fig. 5 Alkaline versus sub-alkaline samples and peralkaline versus alkaline-subalkaline samples plotted in TAS (a), (c) and Zr/TiO2-Nb/Y diagram (b), (d) (Boundaries I and II in (a) are from refs.[7] and [8], respectively)