A nice story by Bernard Baily, co-creator and long time artist on The Spectre & Hourman.
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House of Mystery #97, April 1960 © DC Comics
Art by Bernard Baily
Large impact events, such as Orientale Basin, locally modified the prebasin crater population to ~2 basin radii from the basin center. Basins such as Imbrium, Orientale, and Nectaris, which are important stratigraphic markers in lunar history, are temporally distinguishable on the basis of crater statistics.
The characteristics of pre- and postmare crater populations support the hypothesis that there were two populations of impactors in early solar system history and that the transition occurred near the time of the Orientale Basin event.
Ref.: Global Distribution of Large Lunar Craters: Implications for Resurfacing and Impactor Populations. 2010. James W. Head, III, et al. Science 329: 1504-1507.