Earthlike Mars? Options

[glennwsmith]

All, I know this isn't the right place for this post, but I've looked around and can't find an appropriate, current UMSF forum (Doug, perhaps you could give me some guidance on establishing such) -- so here goes: I think a [the] new paradigm for Martian geology is rapidly coalescing, namely, that Mars is very much like the Earth in terms of the preponderance of water -- except that it is all frozen, and covered under a thin layer of dust/regolith! See, for example, this article:

http://www.skyandtelescope.com/news/41995902.html

Hence the "seepages" found in crater walls; hence the evidence of catastophic flooding -- the result of volcanism melting huge pockets of ice. And I am going to add my own wrinkle (probably not original): that the differentiation of Mars into a rougher southern hemisphere and smoother northern hemsphere represents something like Earth's Pangea stage, ie, the northern hemisphere is a vast frozen sea covered with a thin layer of ice.

[marsbug]

Reading this paper, which i'm sure most people here already have, the thought has occured to me that occasional exceptional events , like small meteorite impacts , could bring preserved ice to the surface in areas where it would not ordinarily be stable, and that this ice might in a smallest of ways melt (short lived thin films on rocks in the debris field etc). Over bilions of years, could events like this account for some of the chemical evidence we see of liquid water on mars? That could have some bearing on theories like an ancient northern ocean.

[centsworth_II]

...this ice might in a smallest of ways melt (short lived thin films on rocks in the debris field etc). Over billions of years, could events like this account for some of the chemical evidence we see of liquid water on mars?

I wonder what the relative contributions to water-mediated changes in mineralogy are of:
1) Hot steam released by the initial explosive impact
2) Lingering sub-surface water/mud created by the impact
3) micro-films as part of an ice-rich environment equillibrium

I wonder if the impacts add much to the changes caused already by near surface ice. There was evidence of water films at the Phoenix site as part of the normal equilibrium between ice, soil, and atmosphere. Why would the same films not exist in regions of near surface ice at lower latitudes even without the impacts?