Timing and duration of mare volcanism in the central region of the northern farside of the Moon

Abstract

Age determinations of lunar mare basalts are essential for understanding the thermal evolution of the Moon. In this study, we performed new crater size-frequency measurements in mare deposits in the central region of the northern farside, consisting of Lacus Luxuriae, Buys-Ballot, Campbell, and Kohlschutter, using high-resolution images obtained by SELENE (Kaguya) Terrain Camera. The estimated model ages of the mare deposits range from 2.7 to 3.5 Ga. On the basis of model ages for all investigated mare deposits in the central part of the northern farside, considering the results of previous studies, we concluded that mare volcanism in this region began at least as early as 3.9 Ga and continued until ∼2.6 Ga. From a comparison of model ages in the region and the South Pole-Aitken basin, we found that mare volcanism in these regions ended at the same time, suggesting that the South Pole-Aitken basin formation impact had a minor effect on mare volcanism in the region.