Near the perimeter of the crater below you can see where the lunar regolith on the left half of the rim, light color, shows three sets of curved deformations expanding outward. The question I have is, were these structures formed during the impact and compressed upward or are we seeing the beginnings of the integrity of the regolith around the crater's rim starting to weaken and settling/breaking away?
Quarter way up on right of photo strip http://wms.lroc.asu.edu/lroc/view_lroc/LRO-L-LROC-3-CDR-V1.0/M123424381LC
An expert will no doubt let us know! To me it looks like "waves" of impact melt, each solidifying to form a terrace.
Sorry to be coming so late to this thread. Looks like I missed a bunch of interesting discussions about a month back when my mom was in the hospital.
Terraces like these are often formed during the impacting processes, as blocks of the crater rim succumb to gravity and drop downwards. This happens at the end of the crater forming process, during what is called the modification stage. However, this type of process is usually associated with much larger craters, where very large terraces occur. It is interesting that we are now starting to see these smaller terraces on the smaller craters. I still think these smaller terraces are related to the crater-forming process, and not recent slope instability, but that has not yet been convincingly determined, one way or another.
I don't think these are "waves" of impact melt, because you would expect the melt to have an outward momentum when it lands on the surface. And, you wouldn't expect the melt to then flow back towards the crater, because there is a fairly steep rise towards the crater rim on the outside of the crater too. So, you wouldn't expect the melt to flow up hill when it's momentum is carrying it away.
I hope this is helpful and not confusing. Please feel free to ask for clarification if I've made a muddle of the explanation
Really great picture, by the way Tom128!