Abstract: Mare basalts were formed from partial melting mantle followed by volcanic eruption to the lunar surface. The thickness of mare basalt plays an important role in the study of magmatic process during Moons evolution and can reflect the depths of the mare basalts source region. It can help us understand the regional volcanism and provide the basic constraints for the thermal and/or magma evolution of entire Moon. Also, the thickness of mare basalt can be used to estimate basalt volumes and indicate the total amount of magma eruption and the thermal state of the Moon. In this paper, by using multi-source remote sensing data and combing the crater morphological characteristics with crater excavation method, we estimated the thickness of Mare Australe basalts in crater and intercrater and analyzed the area, volume, age and magmatic activities. The results showed that the thickness of basalts in crater ranged between 0.11 and 4.75 km with an average thickness of 1.32 km, and the total area and volume of exposed basalts were approximately 57.0610791.66 km2 and 10.2551260.38 km3, respectively. The thickness of basalts in intercrater was found to be 0.012.18 km with an average thickness of 0.34 km, and the total area and volume of exposed basalts were about 6487.8933170.55 km2 and 2711.9711609.69 km3, respectively. As a result, we estimated the thickness of basalts in Mare Australe to be 0.014.75 km and averaged at 600 m, and the total area and volume of exposed basalts to be approximately 2.12×105 km2 and 2.71×105 km3, respectively. By analyzing the ages and distribution characteristics of basalts, we found that the magma eruption activities were mainly concentrated between the Imbrian and Eratosthenian era, along with many localized multi-stage magmatic eruptions and filling processes in Mare Australe, which led to coexistence of the early and late stage basalt in a same basalt unit simultaneously, and the unique distribution characteristics of Mare Australe basalts are related to their topography.

Key words: Mare Australe, Moon, thickness estimation of basalts, magmatic activity