Those blast walls are very perculier, I presume they were generated by a blast wave from an impact. ...
the zoomed in images in the article look as if someone sprinkled talcum powder of rocks and pebbles.
Dave L. on facebook , See my images in flickr
Chairman. Shannonside Astronomy Club (Limerick)
Carrying around my 20" obsession is going to kill me,
but what a way to go.
+ 12"LX200, MK67, Meade2045, 4"refractor