 Immobile elements such as Zr/TiO2 ratios should be used instead for classification.New data suggests that volcanic rocks in the Zedong terrane has a calc-alkaline composition, which is common for volcanic island arc but not necessarily intraoceanic island.Moreover, volcanic rocks in the Zedong terrane share a similar geochemical pattern with Lower Jurassic-aged volcanic rocks from southern Lhasa terrane of the Tibetan Plateau.