A New Global Perspective on Recent Tectonism in the Lunar Maria

Abstract Earth’s Moon exhibits evidence that it is tectonically active. That evidence includes the Apollo Lunar Seismic Experiment detection of shallow moonquakes and the presence of geologically young tectonic features at the lunar surface. Lobate scarps are one such group of young tectonic features that are well studied and widespread across the lunar highlands. A separate, more recently identified class of young tectonic features on the lunar surface are the small mare ridges (SMRs). The SMRs appear to be formed in a similar timeframe as lobate scarps, but until recently, their global distribution and contribution to global lunar strain have remained unknown. Here we present the first global map and analysis of lunar SMRs. We demonstrate that SMRs are geologically young, formed via shallow-rooted thrust faults, and are widespread globally across the lunar maria. We also present an SMR fault displacement–length analysis and estimates of recent contractional strain in the lunar maria. Additionally, our results provide a new inventory of possible shallow lunar moonquake epicenters that are relevant to upcoming lunar exploration and landing site selection.