Using the chemical groups identified by Mitschang et al. (2014) on a local sample of around 700 stars by Bensby et al. (2014) and the new derived ages, I report some properties on the orbital parameters (Rmin, Rmax, e, Zmax, angular momentum) and their temporal evolution. We find that the < Rmax > is nearly independent of age with values from 9 to 11 kpc, while < Rmin > shows a clear trend with age. The < e > and < Zmax > for the chemical groups clearly increase with age.
These preliminary results show a significant variety of orbits for the members inside a chemical group, that may support the idea of the identification of co-eval groups (born same time, not necessarily same place) rather than co-natal (Anguiano et al. in prep.)