Between Moss Crater and Marbach Crater lies an stretch of desert, maybe 100 km wide.
But what's that lying there in the middle of the desert? Take a good look!
You might think that it's an alien skeleton, or maybe a dead dog. However it really appears to be a strange system of canyons. The system is about 25 km in length. I have no idea how such a thing could have formed at that place.
Update 8/9/10: I've probably found an answer to this question: Dissolving subsurface-ice, making the ground collapse in some places, leaving valleys and buttes. However, why the ice was only present in this region and not in the surounding plain remains a mystery.