Mare filled craters on the Moon

Abstract

The lunar craters filled with lava materials represent direct evidence of post-modification processes, and such craters are globally widespread. This study mapped these craters and analysed their diagnostic characteristics, such as approximate infilling lava depth, presence/absence of a central peak, and post infilling floor modifications (e.g. floor collapse and fractures). We have identified 324 mare filled craters, whose diameter ranges from ∼4 km to ∼270 km, with infilling lava depths varying from crater to crater and among regions. We have considered mare filled craters with unbreached rims to investigate the infilling process from the subsurface and categorised mare filled craters into five classes (1a, 1b, 2, 3 and 4). We observed that the location of these craters is predominantly at the periphery of the mare region and at the rims of impact basins, while only a few are found in the highlands and within the mare/basins regions. These craters' infilling age spans from ∼4 to ∼1.7 Ga, which is compatible with our current models of mare chronology. We observed lava filling in several simple craters, which ought to be sourced from relatively shallower recent magma reservoirs. Our study reveals that 54% of floor fractured craters (FFCs) are resurfaced and modified to different degrees by lava emplacement. Therefore, such craters have witnessed multiple events and are referred to as Mare Modified-FFCs (MM-FFCs). Overall, this study provides an understanding of the global distribution and characteristics of craters modified by lava infilling and how they vary globally, suggesting heterogeneous sources.