Top: probabilities of stellar migration (blurring + churning) adopted in this work (see text); they are shown for three birth radii (4, 8 and 12 kpc) and for three snapshots (after 4, 8 and 12 Gyr). Middle: fractions of stars which are born in radii 4, 8 and 12 kpc and are found in galactocentric radius r in the end of the simulation, at T = 12 Gyr. Bottom: fractions of stars found at the end of the simulation in radii 4, 8 and 12 kpc according to their birth radius r. In all panels, radial bins are Δr = 0.5 kpc wide, as indicated by the bin width of the histograms and the size of the coloured boxes.