Re: Q.E.D.: Clathrate Reactions on Mars
First off, you did indeed say that, and you said it in the post immediately previous.
Second, the reference to this particular MGS image was given, and you can answer all of your questions yourself by going to the referenced image.
As you examine the image, remember that there are a number of these linear trenches on Mars, and that they also show up in the Viking images, and that they have been known about by most serious marseologists for quite some time.
Third, Mars is Mars-like, not Earth-like, dammit. Unlike the Earth, Mars does not have much of an atmosphere.
Fourth, therefore, unlike the situation on Earth, any "skips" would take place close enough to the surface of Mars so that they would produce thermal effects on the surface.
ep