ice tectonics --mars a candidate?

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bonzelite

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could possible thermal expansion/contraction of vast ice plates beneath the martian surface be initiated under influence of 1. a geothermal source, however scant and 2. from bombardment of UV, penetrating beneath ground from heating the surface? or a confluence of both? this assumes the heating leads to sufficient melting of ice, and then refreezing as heat is removed, to create adequate subterranean movement. <br /><br />or would <i>presently known</i> conditions of soil density, composition, surface and subsurface average temperature, interior temperatures, be prohibitive to such tectonic processes <i>assuming for sake of argument such ice plates or sheets did actually exist?</i>
 
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CalliArcale

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I seem to recall seeing pictures of Mars that showed what looked like ice floes that might be somewhat like what you're talking about. But my memory is hazy. It's definitely not global.<br /><br />I would think that for ice tectonics to occur on a large scale on Mars there would need to be a lot more ice than there is, which would cause Mars to have a much lower density than it does. But that's just my gut feeling. I hope someone more knowledgeable is available to answer your questions. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
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bonzelite

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good points. <br /><br />i'm just wondering if there is a region beneath the surface that is not necessarily very thick, maybe less than 1km to maybe a few metres, that is an ice bed that interacts with the atmosphere in a cycle. and would this region be robust enough in localized zones to create any subsurface movement <i>en masse</i>, over prolonged periods.
 
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JonClarke

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I would guess that the most likely candidate for the process you are thinking of are the polygonally fractured northern plains, particularly in Acidalia, parts of Cydonia, and Chryse. These are very large scale features, wioth polygons 10's of km on a side. <br /><br />When first seen by Mariner 9 they were hypothesised to be giant permafrost polygons, but they are at least two orders of magnitude larger than those found in the terrestrial Arctic. Because of the scale issue presenty cooling of lava flows or compaction of sediments over buried topography is favoured. But you never know.<br /><br />On a smaller scale there are numerous examples of down slope plastic flow suggesting the presence of shallow ice, rock glaciers, etc.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>
 
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jatslo

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Can't say I have heard of ice tectonics; however, I know a little. Flowing fluids create friction, which creates heat, and numerous ways to get the juices flowing, so of which you outlined. Water is fluid until it reaches a certain temperature, after which, it stops flowing, and just breaks. Breaking causes friction, etc. Ice flows moving downhill cause friction, etc. All of the friction points cause warmth, heat, etc.<br /><br />Now, water would boil off when the pressure no longer supports it, so if there were constant flow outpourings, you would see fog or clouds. It is likely that any glacial activity has stopped, because it is not actively snowing. However, I heard through the grapevine that ice sheets are receding; therefore, this might set some things in motion, or offer evidence that there might be more to Mars than meets the eye.<br /><br />Your tectonics, or macro-fissure events could possibly create lightning, which is essentially friction on a grand scale. I can imagine that if the hypothetical oceans of Mars were capped off by an ice sheet, then it is possible for large fissures to erupt, for whatever reason. These fissures would fill with fluid, then refreeze or evaporate, in the case of Mars, until the oceans emptied of all fluidity, leaving only ice.<br /><br />Ice: Cherenkov Radiation like blue light could cause heat, and polar melting too. UV?! ... could melt exposed ice, yes. Much of Mars ice is buried, and UV does not penetrate the ground much. Microwaves can melt ice, and penetrate layers too. Let's see, did I leave anything out? Probably. <img src="/images/icons/wink.gif" />
 
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CalliArcale

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<blockquote><font class="small">In reply to:</font><hr /><p>Your tectonics, or macro-fissure events could possibly create lightning, which is essentially friction on a grand scale.<p><hr /></p></p></blockquote><br /><br />Lightning is not friction. It is a large discharge of static electricity. The static electricity can be generated by friction, which may be what you were thinking about. However, you're not going to get that kind of a buildup from tectonics. You'll only get a buildup like that in something that isn't grounded, and the ground is, well, grounded. <img src="/images/icons/wink.gif" /><br /><br />I wouldn't be surprised if you could build up a nasty charge in a Martian sandstorm, though. Not enough to cause widespread melting, though. It'd be extremely localized. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
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jatslo

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Yes, you are correct; I typed pretty fast.<br /><br />Ball lightning phenomena has been observed preceding earthquakes, but no Ice that I am aware of. A large piece broke off recently that is the size of a state, and I heard nothing about lightning. However, I am open to the possibility; for example, there was a recent fissure eruption on a Saturian moon that could be related to fricition/plasma, or statiic, like you said... I am open to it, is all. Mount St. Helen's had a lot of ash induced lightning. ...er, friction fracure ball lightning has been duplicated in a lab, I think. <br /><br />No ice lightning, though...
 
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bonzelite

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not to sidetrack on EM too much, but dust particles act the same as convecting moisture that creates separation of charge. the dust storms on mars are, then, gigantic electrical events, on can argue. <br /><br />you do mention that UV does not penetrate too far into the ground. so you mean, possibly, that UV alone is not going to create sufficient heating to affect thousands of cubic km of ice? that is a possbile detractor, yes <img src="/images/icons/frown.gif" /><br /><br />john mentions the huge tracts of the northern plains with massive scale polygonal fractures. after reading most of Hartmann's book on mars, it got me to thinking that mars may have either been once nearly totally covered in ice and it retreated, or there was always a firm bedding of subsurface ice that continually interacted with the atmosphere. the polar caps that sublimate in warmer climes may be, so to speak, only the tip of the iceberg. <br /><br />i'm impatient for MRO to come online.
 
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jatslo

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Someone said something about snow on Mars; you would most certainly have to have precipitate to have glaciers. Equatorial ice sheets would support your idea about fast oceanic ice sheets, but I don't know enough about the topography of Mars to be able to comment on that. I know that a small area of ice is visible above the water, (1% of the ice, for example), so sheet of ice floating 10 cubit feet out of the water would be 10,000 cubic feet submerged. Something like that. It would be difficult to speculate on the depth of the ocean, unless you could track the ice sheets movements, as it scraped to bottom somewhere. Don't know. !?!?!?!?!
 
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bonzelite

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i'm skeptical of any subsurface ocean on mars. as well, couldn't any extant ice sheets act without regular precipitation? i suppose if there was a cycle between the ground and the air, that would imply precipitation. and if it was snow, how would that get farther beneath ground without actually melting and liquifying --something i doubt happens. <br /><br />i'm wondering, though, if there is any liquification, how thick this layer is beneath any ice sheets. and would liquid be necessary to create movement of ice? <br /><br />it would seem that if any subsurface ice is there, it could melt and sublimate, rising to the surface and then to the atmosphere. but, then, how would it become subsurface again without actually flowing back underground as a liquid? i can see it settling back down as frost, as this already happens. so even if it snowed, how does that reunite with subsurface ice sheets, buried beneath miles of regolith? <br /><br />i'm sort of thinking out loud here.
 
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jatslo

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Ice cannot unfreeze by itself. <img src="/images/icons/wink.gif" /> There is a very long list of things that could support your idea; so much, that ICE BLOCKS almost guarantee that you have subsurface water, until you start talking about large reservoirs close to the surface that is. Speculating, with respect to depth of past oceans is difficult. I don't have a problem with oceans on Mars at all, and this should come into light in the very near future, because I some of what I think are ICE sheets/burgs are really massive.<br /><br />Of course, that does not mean that they are thick, though.
 
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bonzelite

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<font color="orange"><br />Ice cannot unfreeze by itself. There is a very long list of things that could support your idea; so much, that ICE BLOCKS almost guarantee that you have subsurface water, until you start talking about large reservoirs close to the surface that is.</font><br /><br />yes. <br /><br />i'm all for liquid water, but i'm very skeptical of some giant underground ocean or reservoir. i'm imagining, as on earth glaciers, water movement under the ice, that which is held as a liquid under the pressure of the ice's mass. <br /><br />and even though Hartmann suggests massive catastrophic flooding on the surface, as is seen in Margaritifer Terra, at the eastern mouth of Vallis Marineris, dumping into the plains of the Chryse, and environs, it could have maybe been a completely under-ice movement of liquid instead of direct exposure to the air, that was allegedly thicker. what i'm imagining is an atomosphere that was not really much thicker. maybe a little. but not lushly thick, like earth. <br /><br />and then this leads to the question of where did, then, mars even get it's water from? and where did the earth get it's oceans from? and was the acquisition process the same between the two planets? or was the process different? <br /><br />in other words, does an atmosphere of sufficient pressure need to be necessarily present to introduce water onto a planet's surface at all? does the water always derive from precipitation? <br /><br />i would think that if there is discovered massive ice sheets beneath the surface of mars, and they are water ice, then they would have been there for billions of years. and without sufficient atmospheric pressure to precipitate <i>anything</i> back to the sub-surface, let alone water, then they sure as h##$%LL are being fed from something.
 
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yurkin

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The polygon features and long cracks that Oppy observed Meridiani Planes may have been caused by permafrost. That’s a theory that changes in the permafrost over the ages caused the cracks in the otherwise even desert. I think what your talking about is a little more dramatic then that.
 
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jatslo

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I think the ice would have to be several hundred feet thick for its weight to support lakes; there are examples on Earth. Sure, all of these phenomena's could have occurred under the ice, as if the ice were a blanket. Biology is very efficient at converting minerals to water, and energy. In fact, water can be used to make more water, by these critters. because water makes it easier to digest the minerals, so you would think that it would be in the best interest of microbes to manufacture water.<br /><br />How is that for all over the map?
 
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bonzelite

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<font color="orange"><br />The polygon features and long cracks that Oppy observed Meridiani Planes may have been caused by permafrost. That’s a theory that changes in the permafrost over the ages caused the cracks in the otherwise even desert. I think what your talking about is a little more dramatic then that.</font><br /><br />right. and i'm suggesting that the features, being so giant, are <i>beyond</i> mere permafrost cracks. whether i'm correct or not is indeterminant. but, yes, more dramatic! <img src="/images/icons/wink.gif" /> i'm even thinking such features could create marsquakes, with perpendicular movement to the surface as well as lateral. <br /><br />and jatslo, good for all over the map, but yet is on topic <img src="/images/icons/smile.gif" />
 
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jatslo

Guest
Where is the evidence for water production from comet's? There is more evidence that microbes convert abiotic petroleums to water than there is for water production from comets. You asked where the water came from, too. <img src="/images/icons/wink.gif" />
 
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bonzelite

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i follow you, but you mention petroliums. where, then, would that have come from? i think there was a thread here not so long ago about oil on mars. i recall the thread was pages and pages long. you have a link to that thread?
 
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yevaud

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Yeah *Snuffle, cough* (frakkin' flu). There was, and I seem to remember he did join in as well. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>
 
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jatslo

Guest
nope. it is in here though. "A" and "B" types. Actually, I think there are few. I was defending a minority in one, I think. Made a good case for oil, as well. <img src="/images/icons/smile.gif" />
 
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