Top plots: [Fe/H] − [α/Fe] trends for the streams selected from the GALAH and APOGEE data in action space in a square of nine regions defined by regions 01a_11a, 11a_21a, 21a_31a and 31a_01a. The solid lines show the running means of the [α/Fe] distributions in bins of [Fe/H], and the shaded regions give the 1-σ dispersions of the data around the means. The bin width when calculating running means is 0.05 dex. Bottom plots: normalised generalised metallicity distributions for the stellar samples shown in the top plots. Here each star is represented by a Gaussian with a central peak at the estimated metallicity and a width given by the uncertainty of the metallicity.