Cratering history of Miranda: Implications for geologic processes

Miranda's surface is divisible into cratered terrain and coronae. The cratered terrain is the most heavily cratered of the terrains and presumably is the oldest. The frequency of craters in the cratered terrain is variable and related to position on the satellite. The coronae are also variably cratered. Elsinore and Arden Coronae have similar crater frequencies and may have formed simultaneously. They are of intermediate agompared to the cratered terrain and to Inverness Corona, which is the youngest major terrain. Graben formation appears to have occurred both before and after the formation of the coronae reflecting periods of global expansion. Miranda's surfaces are, in general, the least cratered and therefore inferred to be the youngest within the Uranian system.