The transition from lunar complex crater to peak-ring basin: Constraints on the morphology and volume of central features

• Published in: Geosystems and Geoenvironment
• Main Authors: Nan Wang, Jie Zhou, Lingli Guo, Ian Somerville, Sanzhong Li, Guangzeng Wang, Pengcheng Wang, Bo Liu
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2022
• Subjects: Lunar; Fresh complex craters; Central feature; Volume; Peak-ring basin; Physical geography; GB3-5030; South Pole; Aitken; Lola; South pole
• Online Access: https://doi.org/10.1016/j.geogeo.2021.100014; https://doaj.org/article/88aefd2c6f054f68954a2c1874e17b4c

The transition from complex crater to peak-ring basin is a hot topic in lunar research. There are many controversies about the formation process of the ring basin, and its formation is closely related to the central features. The data obtained from DEM can determine the volume and morphology of the central features in the complex craters more accurately. We complied a data set of 52 fresh complex craters from the Global Lunar Orbiter Laser Altimeter (LOLA) DEM, and established the Vi-D (internal volume–crater diameter) and Vcf-D (central feature volume-crater diameter) relationships for complex craters in the highlands, mare, mare-highland border, and South Pole Aitken-Basin (SPA) terrain. In general, the Vcf increases as the Vi increases, and the Vcf of the complex craters with similar Vi changes significantly. According to the morphological characteristics, the central features of complex craters can be categorized into 5 main types: the tiny-peak, the multi-peak, the single-peak, the mountain-peak, and the incomplete or complete peak-ring types. The ratio of Vcf/Vi shows the increasing trend from tiny-peak to peak-ring types. The central features of complex craters have significant differences in volume and morphology due to the different terrain conditions. The transition from complex craters to peak-ring basins is closely related to the central features and collapsed blocks. The tectonic uplift collides or thrusts with the collapsed blocks driven by the inward gravity of the instantaneous crater rim, resulting in an upward movement of materials within the transient cavity to form a peak-ring with prominent internal topography. And a larger peak-ring in the morphology and thickness may occur on the highlands due to the stronger collision and compression. We support those peak-ring formation theories that involve the collision and interaction of inwardly collapsing crater rims.