In article , rodders2000
@comcast.net says...
http://www.lyle.org/~markoff/process...6L234567M1.JPG
Opportunity, Sol 103, Pancam.

I don't. But it sure looks like one. Could the wind do something like that?

The obliquity of Mars is believed to have changed periodically on a
relatively short timescale (millions of years). Snow pack layering could
have melted, creating such channels/gullies.

It could be a water drainage channel -- we know that there used to be
standing water here. It also could be the result of aeolian weathering
of a surface that has varying compositions. In the latter case, the
channeling would be controlled not by the erosive force but by the
structure of the materials being eroded.

Doug