New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: We've recently made changes to our user database and have removed inactive and spam users. If you can not login, please re-register.

#1 2019-06-23 10:29:05

Void
Member
Registered: 2011-12-29
Posts: 2,994

Dry sponge model as a scaffold for fluid movements.

I choose to start a new topic, because I think that we may be missing some of the factors that determine how Mars worked, and how Mars now works, because we still see it in terms of an Earth model, and because since we focus on the movements of fluids on Mars, we forget about what it moves through.

By fluids, I mean liquids and vapors, and technically with the assistance of liquids and vapors, the movement of ice as well.  (Although glaciers are an method where ice can be fluid).

I don't think I am showing so much that is new in the various connectable items of fluidity, but I do want to think how these fluids can be facilitated in movements that may interconnect the various "Reservoirs" of fluids and the condensates associated with them.  I am trying to consider a "Whole System" notion for Mars, and other worlds like Mars.

The broken and porous regolith being part of a scaffold that the fluids can interconnect and move through.

Porosity and fractures are opposed by gravitation and cementing/filling processes.

So, Earth, Mars, and the Moon as "Dry Sponges" might presumably have a different nature of porosity.

The Moon, potentially having the most porosity, but that is not sure.  Mars is closer to the asteroid belt, and the outer solar system, so it has probably been battered quite a lot.  I don't have a measure for it, But I am guessing that both the Moon and Mars have a greater porosity than the Earth, even if you remove all of the fluids, and make them "Dry Sponges".  Even the Moon though is not an entirely dry sponge.  We are mostly used to pore spaces largely occupied by fluids, generally mostly liquid water.

For the Moon for all practical purposes there is no atmosphere.  However, there actually is an atmosphere, just rather temporary, and not very much like ours.  But for a dry sponge, should vapors traveling through the dry sponge be considered an underground atmosphere?  I choose to say yes.

For such fluids to move, temperature variations are helpful.  For the Moon, Mars, and Earth, these could be solar, geothermal, and perhaps chemical.  I am guessing that the Moon and Mars, are not very active chemically for this, it seems that they would have equilibrated over time.  But Mars is more likely to surprise.

On the Moon model, for it's atmosphere above ground, we have some condensing processes.  I will presume that water at high latitudes can both condense into near subsurface pore spaces, and also in a few favored locations, might actually condense from water vapor into ice sheets of very small proportions.  Shadowed craters.  The Moon does not have much climatic variation, the poles being relatively constant.  But, underground, in a state of a fairly high vacuum, I wonder if sublimation of ice could inject water vapor into the underground pore space, the underground atmosphere.  Variations in temperature would be helpful for this.  A day-night, summer-winter cycle could help.  Not much to go on there, for the Moon.  Still, a tiny amount of ground heat might erode ice deposits from below.  Probably for the Moon this is very weak.  So, I just wanted to look into its potential and limitations for the Moon.  If it did occur, then we can have a vapors to solids condensation to the very high latitudes, and underground, a solids to vapor sublimation into the regolith.  As I have said, I do not think it would be very powerful.  And I now understand that the solar wind protons + impactors>Hydrated minerals + impactors>Water Vapors>high latitudes (And space as well).  But if there is sublimation from ice deposits into the regolith, as a cold thin vapor, it should have a tendency to migrate towards the equator.  But the "Cap Ice" would run out rather soon I expect, and it could be vented to the above ground atmosphere.  It is interesting though that if there is and has been such a vapor flow, then it could replenish ice layers below some layer of dry regolith, down to slightly lower latitudes.  The drying process of the surface regolith would tend to remove the ice to the upper atmosphere, to be recycled to the poles, or lost to space.  But, the underground process might tend to replenish it.  A balance of powers.  I don't know how strong that can be on the Moon.

But for Mars, it should be rather strong.

And for Mars we have salts of various kinds, in the surface regolith, and presumably some in the lower layers.

So, Mars, having day/night cycles, seasonal cycles, and Precession of Axis, drivers of vapors underground should be much stronger.

So, where on the Earth, the circulation of moisture underground is primarily liquid, there should be less vapor transmission underground.  For ancient Mars, from the information we think we know, we expect that it was also more like that than it is now.

The possibility of very salty spring water emerging in low spots on Mars, seems worth considering, but I think a good model would be for reservoirs of liquids and solids, more joined by water vapor transfers.

For the moment, I see three most prominent types of liquid and solids reservoirs.  The polar caps of course.  A water table below, possibly in general planet wide.  I also see the potential of wet permafrost in places even at the equator.  That would be modified by salts, and would most likely tend to give up moisture from the above ground atmosphere, but be replenished by vapor flows from below ground.

I do think that limited solids>liquid flows could be assisted by underground heat, maybe geothermal, maybe chemical, but I think that generally those may be the lesser process, vapor flows being the greater process.

Analogs for the three reservoirs on Earth, would be Antarctica and Greenland as the major representatives, for the polar ice, a water table in general, with underground vapor flows being much less significant, and for wet permafrost, wet permafrost, and also floating sea ice over the Arctic Ocean.

It does not seem that Mars has now floating sea ice, but it likely did.  For now though, I am more thinking of moisturized near surface permafrost with salts, and perhaps brine channels, or going towards the surface, just tiny crystals of ice/droplets of brines.

The number I have seen for Calcium Perchlorate is potentially participating in a liquid water based solution down to -70 DegC.  There will be other salts that do not support liquid temperatures that low.

But the floating sea ice of our Arctic Ocean, is a more studied item for brine channels than is moist permafrost I think.  It is interesting for supporting photosynthesis inside of brine channels in the ice.

So, I believe that there should be thermal variation brine squeezes in moist permafrost both on Earth and Mars.  In this process salts are excluded from the ice during freezing.  Brine channels resist freezing, and could also thaw during the warm part of the cycle before the ice itself melts or sublimates.  For the Earth's Arctic Ocean, over many seasons this can generate ice which is marginally fit to melt and drink.

The brine channels contents?   Though called brine channels, and having a salt content, how much salt do they have relative to the Arctic waters below?  I am not sure.  They are channels, so perhaps it could be greater than the Arctic Ocean waters below.  I do know that the brine channels approach the surface ice, and allow for photosynthesis of tolerant microbes.

For Mars, I am not going to explore the possibilities for life, certainly not photo life.  Not very much.  Brine channels in moist opaque permafrost, might provide an environment for highly evolved organisms on Mars, or there is no such life on Mars, or even though brine channels may exist, they might be hostile to life.  I am thinking about the process.  Life is a question I set aside for now.

Looking at low temperature melting salts, and cycling variations in temperatures, and presuming a replenishment of moisture from ground vapor flows, I have a sort of model for separations which might occur.  More information is definitely needed to make any such model true to actual facts.  Many facts still not discovered or defined.

Periodic ice squeezing from cold, should push very salty low temperature water based fluids down with the assistance of gravity and perhaps wicking.  It should push ice with less salt upward.  Surface drying should limit the ices penetration to the surface.

So, a layer of a greater amount of Perchlorate salt solution should exist below the ice, to absorb any moisture flows from below.  The low temperature perchlorate fluids if near the solids ice (Which might have some brine channels, should periodically merge and unmerge with the fluids during temperature fluctuations.  Day/Night?  But more seasonal, and axial.

So, I am thinking that it may even be possible, that ice lenses could form below the soil by this process, pushing the relatively dry layer of soil above upwards.  The contest would be the average drying process on the surface, against the average accumulation of moisture into liquids and solids in the moist permafrost.

Snows might have produced thick layers of ice in the temperate areas, that persist against time, but I am thinking that this process could be responsible for maintaining such ice in places near the equator.  It may actually be able to generate the ice layers on it's own even without ancient snowfalls to the equator.

This looks suspicious.
https://www.space.com/38330-water-ice-m … uator.html
https://www.space.com/15859-mars-myster … igins.html
Quote:

Mystery Mars Formation May Be Ancient Volcanic Ash

So, if this is something like pumice, then perhaps porous, and thermally insulation very far down.  Perhaps a conduit for moist vapor flows from far below.  And the dust devils and global dust storms should produce perchlorates which might get into the "sponge" to alter water and ice behaviors.

…...

I have read that the isotopes of Carbon and Oxygen tested by the https://en.wikipedia.org/wiki/Phoenix_(spacecraft)
https://coyoteprime-runningcauseicantfl … ander.html
Quote:

The analysis revealed that carbon dioxide on Mars has proportions of carbon and oxygen isotopes similar to carbon dioxide in Earth's atmosphere. This unexpected result reveals that Mars is a much more geologically active planet than previously thought. In fact, the new results suggest that Mars has replenished its atmospheric carbon dioxide relatively recently, and that the carbon dioxide has reacted with liquid water present on the surface. "Atmospheric carbon dioxide is like a chemical spy," said Paul Niles, a space scientist at NASA's Johnson Space Center in Houston and lead author of the paper. "It infiltrates every part of the surface of Mars and can indicate the presence of water and its history."

……

Well, that is as far as I have gotten on this.  Certainly if some of it is true to facts discovered in the future, those facts will likely modify it.

It's my best try so far, I think.

……

It does suggest that perhaps the first settlement on Mars should be at the equatorial places where this process, if it exists would provide persisting near surface ice/brine deposits.  That is, if there is to be humans on Mars.  That question will be answered by people more powerful than I ever will be.

Done.

Last edited by Void (2019-06-23 12:02:07)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

Offline

Board footer

Powered by FluxBB