Provenance of Ejecta and Regolith Thickness in the Vicinity of the Chang'e-6 Landing Site

The Chang'E-6 mission (CE-6) marks a significant advance in lunar exploration as the first mission to return samples from the Moon’s farside. The study focuses on the pre-selected landing region for CE-6， which comprises three mare units (designated F， L， and B)， to investigate their geological context， with particular emphasis on the regolith's thickness and stratigraphy. Analyses indicate that the regolith thickness ranges from 1.6 to 8.3 m， with a median value of 5.7 m. At the landing site within the F region， the regolith thickness is estimated to be approximately 2.8 m， greater than the maximum drilling depth yet below the regional average. Moreover， the F region exhibits a higher density of concentric craters， suggesting enhanced rock exposure and providing insights into the area’s geological characteristics. Ejecta modelling demonstrates considerable variation in deposit thickness， with the CE-6 site featuring a thinner ejecta layer (0.9?m) compared to other locations， such as CE-4， thereby indicating a distinct depositional history for the CE-6 landing site. Furthermore， the stratigraphic sequence map developed for the landing site offers valuable information regarding the Moon’s subsurface composition and geological history.