49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083) 2782.pdf A WRINKLED MOON T. J. Thompson1, M. S. Robinson1, T. R. Watters2 1Lunar Reconnaissance Orbiter Camera, School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA; 2Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, DC 20560, USA. (
[email protected]); Introduction: Wrinkle ridges are tectonic land- forms characterized by linear topographic highs with complicated surface expressions involving a broad arch and a sharp ridge interpreted as the result of thrust fault- ing from comparison with earth analogs [1, 2]. These features were discovered through telescopic observa- tions of the Moon [3], and were later found on several terrestrial bodies by observing spacecraft [2, 4]. Lunar wrinkle ridges are concentrated in the mare basalts of the Moon’s nearside (Figure 1). The question of why wrinkle ridges are confined to mare basalts is partially Figure 1: Global map of orientations of wrinkle ridges com- addressed in the mascon tectonic model in which im- pared to nearest spot on the bounding mare boundary. Light pact basins are filled with approximately 4 kilometers blue features are selected as being 10 degrees or less differ- of basalt denser than the average lunar crust, causing an ent than the near segment on the boundary. Pink features are adjustment in the crust to accommodate the added mass, selected as being 80 or more degrees different than the near where this accommodation generates the compressional segment on the boundary. stress necessary to form wrinkle ridges [5, 6, 7, 8, 9].