Rocky substratum in MERs' images

The new images from Meridiani apparently show a similar folded or corrugated
substratum of rock to the "Mars mud" at Gusev, like hastily applied cake
icing---apparently cleaned of sand or dust by the airbag retraction around
the rovers. Lava flows? If Rover2 is in a crater, some peculiar impact
dynamics? If both materials, from opposite sides of the planet, are really
formed in similar ways, what are the implications?

As I remember, my last reading on Martian "geo-"logy (a SciAm article,
probably out of date), said that Mars lacks the equivalent of Earth's plate
tectonics, so that all Martian vulcanism was of the "crust melt-through"
variety. How would this affect the development of Mars' terrains and
climate?

JJ Robinson II
Houston, TX
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* JOKE *
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* SERIOUS, *
* (HONEST!) *
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* SARCASTIC *
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