Distribution of sample stars in [Fe/H] − v_Φ plane, for different intervals of [Mg/Fe] abundances, as indicated in legends at the top of each panel. [Mg/Fe] bins have been defined as in Fig. 4. The number of stars in each metallicity interval are also given in the lower-left corner of each panel. Colours of each point represent the [Mg/Fe] ratio as indicated in the colour bar on the right-hand side of the figure.