Earth Planets Space, Vol. 63 (No. 1), pp. 5-13, 2011
Tomokatsu Morota1, Junichi Haruyama1, Makiko Ohtake1, Tsuneo Matsunaga2, Taichi Kawamura1, Yasuhiro Yokota2, Chikatoshi Honda3, Jun Kimura4, Naru Hirata3, Hirohide Demura3, Akira Iwasaki5, Takamitsu Sugihara6, and LISM Working Group
1Institute of Space & Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara 229-8510, Japan
2Center for Global Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
3University of Aizu, Ikki-machi, Aizu-wakamatsu 965-8580, Japan
4Center for Planetary Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan
5Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan
6Center for Deep Earth Exploration, Japan Agency for Marine Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa 236-0001, Japan
(Received August 19, 2009; Revised January 25, 2010; Accepted February 22, 2010; Online published February 21, 2011)
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 Kohlschütter, 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.
Key words: Moon, mare volcanism, lunar farside, Feldspathic Highland Terrane, the South Pole-Aitken basin, crater size-frequency measurement.