GMM decomposition of Gaia-ESO survey and APOGEE samples in the [α/M] vs. [M/H] plane. Points depict the APOGEE working sample. Contour lines draw the density distribution of Gaia-ESO survey GMM data groups. A vertical shift of Δ [α/ M] = 0.1 dex was applied to the APOGEE sample to obtain a better agreement between the two data sets. Color coding is set to be consistent with the one used to represent data groups throughout this paper.