age-metallicity relation

The age-metallicity relation (AMR) is a reverse correlation between the age of stars versus their metallicity within the local Milky Way: older stars tend to have less metallicity. Additionally, those stars with a particular such age-metallicity relation tend to have a similar velocity dispersion, thus there exists a age-velocity-metallicity relation (AVMR). Such an AMR is consistent with the fact that as time passes, supernovae increase the metallicity of molecular clouds that are star forming. Age also affects the specifics of their abundances.