Further clays found by Spirit in the Columbia Hills?

[exoscientist]

Saw this on the Unmannedspaceflight.com site:<br /><br />P12A-04 <br />TI: First Low-Iron Materials on Mars and Possibility of a Major Montmorillonite Component.<br />"Chemical trends implicate Mg sulfates and Ca phosphates are important but minor accessory minerals. Moessbauer analysis indicates some or all Ti to be present as ilmenite. The remaining component has high Al and Si abundances in proportions within the range of classical montmorillonite compositions found at various locations on Earth, including their correspondingly low concentrations of major cations. Typically the result of weathering of basaltic ash and often associated with more arid environments, the formation of montmorillonite or its alteration-product precursor implies that significant aqueous activity to facilitate geochemical separations occurred."<br /><br />Montmorillonite is a type of clay.<br /><br />Steve Squyres had mentioned that Independence rock, among those that appear to contain clay, was very unusual:<br /><br />Mars rovers keep breaking new ground <br />Opportunity traverses sandy ‘maze’; Spirit studies strange bedrock. <br />By Leonard David <br />Updated: 8:56 p.m. ET July 19, 2005 <br />"During its ascent of Husband Hill within the Columbia Hills, the robot came across a “very cool outcrop” of layered bedrock that has been tagged as Independence Rock, Squyres said. <br />“We’ve thoroughly worked it over with all of the arm instruments now, and it’s very strange stuff,” Squyres reported. He said it was one of the oddest things seen at Gusev. <br />“I’m not ready to go into much detail here about the chemistry and mineralogy yet, since we’re still chugging through the data,” Squyres noted. The rock is clearly highly altered, sporting an unusually low iron <div class="Discussion_UserSignature"> </div>

 

[bonzelite]

jon has got to drop in here and sound off on this one.

 

[JonClarke]

Someone called?<br /><br />All sounds reasonable to me. The clay alteration seems very localised. This suggests: 1) hydrothermal alteration along fluid pathways, 2) buried weathering horizons along the tops of flow units, 3) relatively thin interflow sediments (inc. altered tuffs, 4) combination of some or all of the above.<br /><br />Just guessing of course.<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>

 

[paulanderson]

Good stuff.<br /><br />And another good clay article posted today on Scientific American:<br /><br /><b>Martian Claymation</b><br />An ancient, watery Mars was not always an acid bath<br /><br />http://www.sciam.com/article.cfm?chanID=sa004&articleID=0003A221-B3F9-137B-B35983414B7F0000<br /><br />Again about the carbonates though, what about the traces that Spirit saw at the beginning of the mission and the trace levels seen globally from orbit, as mentioned in the same MER update from 2004? I posted the link before, would have to find it again now...<br />

 

[silylene old]

Montmorillonite clay is one of the catalysts found to photoreduce CO2 to methane. It is interesting this clay is now being reported.... <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[bonzelite]

that is interesting. it may add credence to an abiotic methanogen.

 

[jatslo]

As a trapped gas that is eroding out at a constant rate? Mars is very corrosive, so I thought.

 

[bonzelite]

yes. you're right. a superoxide surface. as well, as has been stated many times by others, CH4 will decay very quickly in the thin, UV bombarded air of mars. if the clay were prevalent enough, chemically reacting with CO2 to get CH4, it may outgas at the surface constantly. <br /><br />i know this is asking a lot of the clays. it may contribute, then, to the methane source, but not be solely responsible. the olivine idea seems the best yet and "safe." i'd like to think it was biogenetic. but what i like and what is actually there may not be in agreement.

 

[jatslo]

If that were true, then the CH4 concentrations would be strongest at the source, and it is too bad the rovers cannot sniff it out. <img src="/images/icons/frown.gif" />

 

[bonzelite]

probably so, yes.<br /><br />as well, there is an idea that the outgassing of the CH4 comes from pourous cliff walls or crater walls, ie, venting. <br /><br />even though i want life to be responsible, i have taken a shine to the olivine theory of CH4 creation. i know that theory may be wrong, and i indeed hope it is, but it offers a sensical geologic explanation.

 

[paulanderson]

A new methane update from Vladimir Krasnopolsky:<br /><br /><b>Some problems related to the origin of methane on Mars</b><br /><br />Icarus - December 15, 2005<br /><br />http://tinyurl.com/cjf69<br /><br />If clays contribute to the methane at all, shouldn't there be a correlation between the clay deposits and localized sources of the methane? I don't know if there is yet or not, just an observation.<br />

 

[JonClarke]

The last line of the abstract (can't access the whole paper) is the most interesting:<br /><br />"The overall results strengthen the biogenic origin of martian methane and its low variability."<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, based on Earth models, I consider life the primary basis for CH4 until proven otherwise. <img src="/images/icons/wink.gif" /> For instance, I red the following just recently:<br /><br /><font color="orange">"If you add <font color="white"><i><b>hydrogen cyanide, acetylene and water together in a test tube, and give them an appropriate surface on which to be concentrated and react, you'll get a slew of organic compounds including amino acids and a DNA purine base called adenine</b></i></font>" said co-author Geoffrey Blake of the California Institute of Technology in Pasadena. “Now, we can detect these same molecules in the planet zone of a star hundreds of light-years away." REF#154846</font><br /><br />That sounds like a good jump on potential life-forms to me. <img src="/images/icons/smile.gif" />