Simulations Show Liquid Water Could Exist on Mars / New Phoenix Lander results

[JonClarke]

There is always one in the room <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /><br /><br />With VERY few exceptions, minerals are always denser than brines. Ammonium minerals are very unusual because of their solubility. the most common ammonium sulphate minerals are the ammonium jarosites and alunites.<br /><br />Ammonium minerals almost always form complex salts. One such mineral is ammonioalunite, with a density of 2.4. The most common ironsulphate is jarosite. Like ammonium salts, enough simple iron sulphates are very rare. I have no idea why. The density of jarosite is 2.7.<br /><br />Almost all sedimentary minerals have densities of />2.<br /><br />Two useful web sites on minerals are http://webmineral.com/data/ and http://un2sg4.unige.ch/athena/mineral/mineral.html<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>

 

[bonzelite]

ok, given the high hematite content of the blueberries, ie, density greater than saline, how then are these spherules scattered about like buck shot everywhere, separated out from their concretion matrices? why do they survive as they are? <br /><br />it somewhat makes a case for floating spherules, albeit a tenuous one, considering your specific gravity idea. as well, they could have been simply deposited there by runoff, tumbling and settling at low spots of drainage. <br /><br />if my memory serves me, i recall seeing pics of blueberries embedded in sedimentary rock layers. over aeons, as the sediment pulverizes, the blueberries are liberated.<br /><br />

 

[rlb2]

<font color="orange">Almost all sedimentary minerals have densities of >2.<font color="white"> <br /><br />I hate to be a pain in the but, but, as you know better than I do the geological processes on Mars was different than on earth, Earths density is 5.5 and Mars is 3.9- Mars gravitational field is .38 of Earths. The rover did some easy rock crushing and some of that might be because the rocks aren’t as dense on Mars as they are on Earth, more filled with voids. On earth it may be more a matter of if something is buoyant or not by how much empty voids are in the material thus the large steal reinforced supertankers can move across the oceans, for instance pumice-stone has a specific gravity of .641, I understand that pumice is an extreme example because it is very porous, but....<br /><br /><font color="orange">There is always one in the room<font color="white"> <br /><br />You can throw that piece of chalk at me now.<br /></font></font></font></font> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[JonClarke]

They are concentrated on the surface because they are harder. The concretions are haematite, which is moderately strong (although sometimes they are crushed by the rover) in a matrix of mostly sulphate which is easily crushed by the rover or drilled by the RAT. The difference is beautifully shown in those images of concretions on stalks. So what happens is the concretions tend to form a resistant lag. You see the similar things on earth. For example sometimes you get gravelly sand, the sand gets blwon away but the gravel is left behind, forming a layer that resists erosion. Or you get in lateritic weathering environments growth of haematite granules in the soil. When the soil is erode they granules form a surface lag. <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>

 

[JonClarke]

What you are seeing there is the difference between minerals and rocks.<br /><br />Minerals have a very specific set of properties including a distinctive composition and a definite crystal structure (amorphous substances such as glasses are not minerals). Thus minerals are characterised by invariable properties visible in hand specimen such as hardness, density, cleavage, form, streak, etc. Plus a whole range of more arcane properties such as conductivity, electron density, fluoresence etc. Change one of the basic properties and you have a different mineral. Graphite and diamond are both chemically C, but because of different crystal structure, have very different properties and are classed as different minerals. So diamond will be diamond and graphite graphite on earth, the Moon, Mars, or planet in orbit round Vega.<br /><br />Rocks are aggregates of minerals or other particles. Thus their properties vary markedly. A sandstone can be as hard as granite or so friable you can crush it in you hand - even if made of a mineral like quartz whgich is harder than steel. The strength of rocks is due to many factors - the properties of the minerals in the rock, their size, how they interlocked, how they are cemented etc. What we see on Mars is the response of unconsolidated materials and rocks - aggregates of minerals - in response to the rover actions. Some, like the basalts are hard, others like the sediments are weak but coherent, some like the dust and sand deposits are unconsolidated.<br /><br />Lastly, gravity does not seem to have major effect on mineral formation. Meteorites, which form in essentially zero gravity, have mostly familiar minerals, as do lunar rocks and martian meteorites. There are unique minerals in meteorites, lunar rocks, and doubtless on Mars, but these are new compositions or crystal arrangements, not familiar minerals with different fundamental properties.<br /><br />Hope this makes sense!<br /><br />Jon <br /><br /> <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>

 

[jatslo]

My sluice traps gold that way. <img src="/images/icons/wink.gif" /> Of course, water works much better than the wind. <img src="/images/icons/smile.gif" />

 

[bonzelite]

i understand. the concretions, spherules of hematite, remain behind whilst the looser sulfate matrix, sand/sediment, erodes away. the sulfate/hematite indicates the past presence of water.

 

[rlb2]

<font color="orange">What you are seeing there is the difference between minerals and rocks.<font color="white"><br /><br />I’m not a geologist like you I'm more a sideline interested participate. One of my three Engineering degrees is in Civil engineering; however I’m not practicing in that field today, I had to know about Hydrology, Soils, Fluids, Inorganic Chemistry, Physics etc, etc. etc. <br /><br />I have no problem with what you said however there may be more void spaces in Mars rocks than here on Earth especially on the surface therefore the rocks as a hole would be less dense. <br /><br />I’m not debating the composition of the materials as such, even that varies, ie that’s how we can tell difference between a Martian rocks and Earth rocks. Most meteorites we found on earth are the hearty type, they were very dense before entering the earths atmosphere and had a better chance of surviving the fiery entry therefore our judgment of the density of all asteroids may be skewed. If you look at the density of asteroids then they vary widely. <br /><br />The hematite may only be a surface coating on the Spherules. They only came to that conclusion about the Spherules containing hematite after checking out a group of them together, I don’t know if they know anymore about what other type material they are made out of.<br /></font></font> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[rlb2]

<font color="orange">it somewhat makes a case for floating spherules, albeit a tenuous one, considering your specific gravity idea.<font color="white"><br /><br />True, someday we may know the rest of the story when they send better instruments that can check things out in the micro scale and give us good color images and spectro readings of the micro world like we were peering through a microscope.<br /></font></font> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[rlb2]

1P185979083EL5M1 <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[bonzelite]

"The hematite may only be a surface coating on the Spherules. They only came to that conclusion about the Spherules containing hematite after checking out a group of them together, I don’t know if they know anymore about what other type material they are made out of."<br /><br />--this is actually a very far-reaching idea, imho. that the rovers can crush some of the spherules makes a case for their densities, and perhaps their compactedness/concreteness, being very porous, like "dirt clods." <br /><br />in other words, instead of them being like lead mini-balls from civil war era rifles, they may be more chalky, as if to crumble. this incites speculation as to their texture, ie, what they would behave like in a human palm when rubbed to identify texture. <br /><br />for that matter, the structures throughout mars may be very delicate and easily disrupted or destroyed by earth-like forces upon the land: mars is less dense, smaller, with less gravity, and with a far thinner atmosphere. i never quite thought about this unti just now. <br /><br />we may get to mars with a human presence only to swiftly destroy vital clues and unprecedented beauty because of a potential heavy-handedness that is endemic to earth life.<br />

 

[JonClarke]

A sluice is a good analogy for the formation of lags. They of course occur under water, on the sea floor and in rivers, as well as in wind eroded regimes.<br /><br />I am not sure whether a water or air would be more effective. Water is a denser fluid, so a more effective transport, and more viscous, so more efficient a separating out very dense materials. However the density contrast for most normal materials (gold excepted) is higher in air than water. I don't know the fluid equations well enough to give a definitive answer on this.<br /><br />As an aside, economic lags occur in wind-eroded regimes as well as water eroded ones. In Nambia diaomonds have been mined from lags between dunes. In areas with scarce water dry blowing has been developed as an alternative to water sluicing for gold mining and prospecting.<br /><br />Jon<br /><br /><br /><br /> <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>

 

[JonClarke]

The concretions seem to be texturally and compositionally homogenous throughout, judging from ones that have been rated. They are probably haematite all the way through.<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>

 

[JonClarke]

"True, someday we may know the rest of the story when they send better instruments that can check things out in the micro scale and give us good color images and spectro readings of the micro world like we were peering through a microscope. "<br /><br />MSL and ExoMars should deliver close to that, all being well. <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>

 

[jatslo]

<font color="yellow">A sluice is a good analogy for the formation of lags. They of course occur under water, on the sea floor and in rivers, as well as in wind eroded regimes.</font><br /><br />Correct, stratification is the means by which the heaviest elements are extracted via natural or mechanical processes. Earthquakes, sound, etc will also impact sediments. I also use metal detectors to locate pockets, and on occasion, I use black lights to look for phosphorous like opals, gemstones, etc. In areas with high concentrations of hematite, I do the best in. Copper, silver, lead, platinum, etc.<br /><br /><font color="yellow">I am not sure whether a water or air would be more effective. Water is a denser fluid, so a more effective transport, and more viscous, so more efficient a separating out very dense materials. However the density contrast for most normal materials (gold excepted) is higher in air than water. I don't know the fluid equations well enough to give a definitive answer on this.</font><br /><br />Water is far more efficient at extraction, or liquids, because I can alter the state of water to increase the performance of extraction. For example, I can add detergent to decrease viscosity. <br /><br /><font color="yellow">As an aside, economic lags occur in wind-eroded regimes as well as water eroded ones. In Namibia diamonds have been mined from lags between dunes. In areas with scarce water dry blowing has been developed as an alternative to water sluicing for gold mining and prospecting.</font><br /><br />Yes, locating the source involves sampling in these places; however, the actual mining occurs on top of the extinct volcano that spewed them, because those tubes are more dense (more diamonds per cube). The diamond miners use lots of water and UV. Diamonds refract/reflect light; mostly blue, I think.

 

[JonClarke]

We are getting right off topic here....<br /><br />Would adding detergent reduce viscosity? Or am I thinking of surface tension? <br /><br />Whereabouts do you do your prospecting?<br /><br />The Nambian deposits are all reworked from pipes further inland. The major mines are located on beaches, modern or ancient, some mined beaches are uplifted to well above sea level, some are under over 100 m of water. Alluvial channels have been mined as well. The aeolian accumulatons are minor, largely because of grainsize issues, I believe.<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>

 

[jatslo]

I mine in Northeast and Southwest Oregon mostly, but I like Northern California, Idaho, and Washington too. I would love to mine Mars. <img src="/images/icons/wink.gif" /> When do you think humanity will start classifying materials on Mars? <br /><br />Surface tension, plus, cleans microgold out of sticky substances.

 

[JonClarke]

We have started classifying Martian materials chemically, mineralogically, and according to mechancial properties. Obviously it will take centuries to really get to know the surface, even with human missions.<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>

 

[jatslo]

Well I would like to see some work rovers up there, excavating cubes, and classifying materials similarly to how archaeologists work, and then we can cover the hole and pressurize in preparation for humans. For example, we could pour the excavated materials into a vibrating classifier that send materials along a conveyor that passes underneath a number of scopes for spectra analysis of possible fossils or whatever. The team will dig a hole, and our human team can cover and pressurize the hole when they get their. Let's get some real work accomplished; let us move a truckload.

 

[bonzelite]

i agree.

 

[JonClarke]

Definitely! I assume you had read about the robotic village concept which would do this sort of work? I suspect we would see this done first on the Moon, the need is more pressing there, and then applied to Mars.<br /><br />But we digress!<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>

 

[jatslo]

Nope; I just made it up, because that is pretty much how I gold mine with various vacuums and accessories. When it rains, I place a tent and tarp over the dig, if I am, in fact, working dry with a shopVac.

 

[jatslo]

http://www.robotvillage.com/

 

[JonClarke]

People talk about mining on Mars sometimes, and you get the impression they mean something the scale of a big strip mine. When in fact the level is going to be much more like what you might do. At least at first.<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>

 

[jatslo]

Yep, I imagine just a couple of rovers could dig a pretty good hole in about one year. One 12" cube per day would make a significant hole. It is a lot easier to dig in cemented materials than actual rock, but rock might make a better habitat. I average between 1 to 3 cubic yards per day, depending on how much rock I have to pry away, and I make about $80 per yard on a good day.