  In this paper we present a crater age determination of several terrains
associated with the Raditladi and Rachmaninoff basins. These basins were
discovered during the first and third MESSENGER flybys of Mercury,
respectively. One of the most interesting features of both basins is their
relatively fresh appearance. The young age of both basins is confirmed by our
analysis on the basis of age determination via crater chronology. The derived
Rachmaninoff and Raditladi basin model ages are about 3.6 Ga and 1.1 Ga,
respectively. Moreover, we also constrain the age of the smooth plains within
the basins' floors. This analysis shows that Mercury had volcanic activity
until recent time, possibly to about 1 Ga or less. We find that some of the
crater size-frequency distributions investigated suggest the presence of a
layered target. Therefore, within this work we address the importance of
considering terrain parameters, as geo-mechanical properties and layering, into
the process of age determination. We also comment on the likelihood of the
availability of impactors able to form basins with the sizes of Rachmaninoff
and Raditladi in relatively recent times.
