Here's a New Scientist story about how the surface of Enceladus as viewed in the recent close flyby from Cassini is hard to understand. It is littered with boulders about 10 to 20 meters in diameter.
http://www.newscientistspace.com/article.ns?id=dn7692

Here's the image that inspired this story.


The image is a little blurry, I suspect because of the high speed that Cassini had relative to the target.

BTW, I was very surprised how few images of Enceladus' surface have been released even to the Raw Images section of the Cassini website. I wonder if there really were that few taken. Many seem to have missed the moon altogether.

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First impression-- it looks like expansion faulting from after the era of maximum bombardment. As they say, the scarcity of boulders in the low relief is very puzzling. S

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Pick one.

As a first guess, I'd say the scarcity of boulders in low relief is because of flooding of the trenches after the period of boulder distribution.

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