SEISMICALLY INDUCED REGOLITH POOLS IN SIMPLE CRATERS ON THE MOON

Previous studies have shown impact induced seismic shakings may erase craters on comets and asteroids, and alter the shape of craters on larger planetary bodies such as the Moon. Here, we use computer simulations and remote sensing to demonstrate this diffusive process causes the formation of pools of fluidized regolith funneled from the crater walls onto its floor. We implement a surface evolution numerical model that includes primary and secondary cratering, realistic ejecta that is affected by topography, and seismically induced slope diffusion. We identify several craters whose floors are submerged with regolith in images obtained by the Lunar Reconnaissance Orbiter Camera (LROC), and use our model to explain preferential rock burial in topographic depressions on these craters’ floors. Finally, we postulate this thicker regolith may act as a diffusion barrier for ice deposits cold-trapped within permanently shadowed craters near the poles of the Moon. Our findings may help explain recently published results showing ice is more abundant on the Mercury and the Moon than previously thought.