[M-IS21] Planetary Volcanology

[MIS21-P02] Reconsideration of age determination procedures of lunar mare basalts based on crater counting

*Tomokatsu Morota¹ (1.Department of Earth and Planetary Science, The University of Tokyo)

Keywords:Moon, mare basalt, crater chronology

The ages of lunar basalts are fundamental for understanding the duration and timing of mare volcanism and the lunar thermal evolution. The eruption ages of mare basalts have been estimated mainly by cratering chronology using image data. Recently, Chang'E-5 mission collected new basaltic samples from the nothern Oceanus Procellarum. The radiometric ages of returned samples are estimated to be ~2.0 Ga (Che et al. 2021, Li et al., 2021). On the other hand, previous studies based on crater counting have suggested various model ages from 1.2 to 2.5 Ga for the basaltic unit including the Change'E landing site. In the presentation, I will discuss what causes such large differences in estimated model ages among reseachers.