  Recently a number of studies have identified small lunar geologic structures
to be <100 Ma in age using standard remote sensing techniques. Here we present
new crater size frequency distributions (CSFD) and model ages using craters D>
10 m for 5 small target units: 1 Irregular Mare Patch (IMP) in Mare Nubium and
4 regions located on lunar wrinkle ridges in Mare Humorum. For comparison we
also date another IMP found in a recent study in Mare Tranquillitatis (Braden
et al., 2014). Absolute model age derivation corresponds to 46$\pm$5 Ma and
22$\pm$1 Ma for Nubium and Sosigenes IMP. We show that for IMPs and in nearby
control mare regions similar production-like cumulative log-log SFD slopes of
-3 are observed. In contrast control mare regions in Mare Humorum exhibit
shallower equilibrium slopes from -1.83 to -2. 3 out of 4 wrinkle ridges appear
to be in equilibrium but with crater life times lower than on the corresponding
maria. Low crater frequencies on one wrinkle ridge result in an age of
8.6$\pm$1 Ma. This study region contains 80% fresh craters which suggests that
the crater population is still in production indicative of a recent resurfacing
event.
