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SUMMARY:  The March 2, 2004 NASA announcement of water, sulfates, and salts continues to point to a mineralogical assemblage of standard hydrothermal and volcanic origin.  Hydrothermal waters are a typical, late stage, fractional component of almost all cooling magmas.   In my opinion, the mineralogy (revealed in NASA press releases to date), argues against a fluvial, lacustrine, or oceanic origin for the environments currently under study by Rover instruments.   Further, NASA?s March 2 announcement is consistent with my Feb 27 posting regarding current Rover evidence of basaltic and volcanic deposits (please see copied post, below).

GEOLOGICAL ISSUE: As of March 2, surface outcrops examined by Spirit and Opportunity appear to be predominantly volcanic rocks overlain by recent aeolian sediments.  Therefore, it is not news that water was a major component in Martian vulcanism.  Water is the principal mobile constituent of all rock melts, and water comprises from one to eight percent of rock magmas.  (Whenever we take our morning shower, we are bathing in a fractional constituent of the magmas that formed our terrestrial crust.)   Briny solutions rich in halides (salts) and sulfates are a typical component of hydrothermal solutions.  Further, igneous calcium carbonate (CaCO3) is a well-documented water-associated component of terrestrial igneous rocks (fueling fierce debate in the early 1900?s as ?The Carbonatite Problem?). 

OPINION:  Is it appropriate for NASA scientists to persistently argue for a fluvial, lacustrine, or oceanic origin to explain a typical volcanic and hydrothermal environment?  We do not need to go to Mars to know that there is water on Mars.  Further, why does NASA not release the Rover scientific data as it is gathered, so that the public may draw its own conclusions?   Petrology teaches us the following:
1.  If volcanic rocks are found on Mars, then these rocks will almost certainly contain minerals formed by hydrothermal fluids; and
2.  Typical hydrothermal mineralogy includes halides, sulfates, and carbonates crystallized from water, as well as minerals altered by the pH extremes found in aqueous hydrothermal systems.

MINERALOGICAL ALTERATION:  March 2 press releases indicate the discovery of Jarosite on Mars, and also suggest mineralogical alteration by water.  To quote, "The second question we've tried to answer: Were these rocks altered by liquid water? We believe definitively, yes," Squyres said (CNN.com, March 2).   However, these press releases fail to explain that Jarosite is a mineral found in volcanic fumeroles.  Specifically, Jarosite; KFe3(SO4)2(OH)6; Potassium Iron Sulfate Hydroxide; a minor member of the Alunite group of sulfates.  Jarosite is noteworthy in its unusual occurrence  as concretions or mulberry-like forms known as 'moronolite?. Alunite, for which the group is named, can be formed through action of hydrothermal sulfuric acids reacting with potassium feldspars.  (Note:  I must do further research to determine if Jarosite is also a product of hydrothermal sulfuric acids, and thus comprises the evidence of "rocks altered by liquid water" indicated by NASA.)

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Posted: Feb. 27 2004, 13:39
Topic: Is Rover evidence arguing against water?

I fear this will not be a popular post...

QUESTION: Do folks on this site know where the ?general public? can locate more substantive scientific & mineralogical "press releases" that provide scientific data beyond what is released by NASA to the popular press and to high school students? I am interested in more specific mineralogical data that have been uncovered by Spirit & Opportunity. The Rovers have been on Mars for weeks now, grinding and analysing, so where are the details available?

REASON: As I review various articles and press releases for the current Rover mission, I find many NASA comments about "interesting", ?weird?, and ?surprising? features....but very limited specifics on Mars mineralogy or petrology uncovered by the current Mars Rover instruments. Various analyses and grindings have been performed for several weeks, and I have sent several emails to the Cornell/ Athena/ NASA/ JPL Contact email addresses, but have not received a reply. (However, I am sure they are quite busy to be answering lots of emails.)

OPINION: Unless I am mistaken, thus far it appears that Spirit & Opportunity have uncovered evidence that argues in favor of typical basaltic petrology, and against the presence of significant water in the regions of investigation, rather than in favor of significant water. All rock magmas possess some quantity of water, so any geologist knows without traveling to Mars that water was present in the geohistory of Mars. Indeed, water will be found on virtually ALL stony planets in the universe. However, was the quantity of Martian water adequate to generate life, and were the Martian aqueous environments favorable to the creation of life? NASA's Rover press released evidence thus far argues against it for the areas of investigation.

ROVER EVIDENCE: Specifically, the geological information listed below can be gleaned from the NASA Rover press releases as of Feb 27, 2004, and each of these argues in some way against signficant water or a sedimentary geological history in the Mars regions of investigation:

1. BASALT - Sol 1, First Rover landed in a basalt field, perhaps vesicular (basalt was immediately apparent in Rover photographs released on sol 1, as well as from subsequent analysis and core drilling).
2. OLIVINE - Presence of olivine (both in situ and in soil?), argues against significant surface water, due to olivine?s rapid erosion by water due to its disequilibrium with surface environments.
3. NO GOETHITE - Presence of crystalline hematite (Fe2O3), while simultaneously lacking evidence of an associated goethite or a gossan/ iron hat structure to indicate hydration effects of water on hematite (generally, Fe2O3 + HOH --> 2FeO(OH)). Gossans are how hematite is typically found on earth for iron mining.
4. VOLCANIC TUFF - A spheruled, layered, "salt and pepper" rock that looks very much like a typical, terrestrial volcanic tuff.
5. MAFIC VOLCANICS - General Martian geological features consistent with terrestrial mafic volcanic activity.
6. NO STRONG SEDIMENTARY/ GEOCHEMICAL EVIDENCE - No strong evidence thus far to indicate significant water-born sedimentary, evaporitic, or carbonate geochemical activity; versus mineralogical evidence that more likely points to carbonates and salts of igneous/ hydrothermal origin.
7. TYPICAL WIND-BLOWN DEPOSITS/ FEATURES - A variety of soil deposits and structures that seem to suggest wind-blown alluvial deposits (?Qal?) overlaying in situ outcrops of pyrochlastic and mafic lava flow petrology, versus deposits and structures of sedimentary origin.

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