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Smectite clays in Mars soil - Evidence for their presence and role in Viking biology experimental resultsEvidence for the presence of smectite clays in Martian soils is reviewed and results of experiments with certain active clays simulating the Viking biology experiments are reported. Analyses of Martian soil composition by means of X-ray fluorescence spectrometry and dust storm spectroscopy and Martian geological history strongly suggest the presence of a mixture of weathered ferro-silicate minerals, mainly nontronite and montmorillonite, accompanied by soluble sulphate salts, as major constituents. Samples of montmorillonite and nontronite incubated with (C-14)-formate or the radioactive nutrient medium solution used in the Viking Labeled Release experiment, were found to produce patterns of release of radioactive gas very similar to those observed in the Viking experiments, indicating the iron-catalyzed decomposition of formate as the reaction responsible for the Viking results. The experimental results of Hubbard (1979) simulating the results of the Viking Pyrolytic Release experiment using iron montmorillonites are pointed out, and it is concluded that many of the results of the Viking biology experiments can be explained in terms of the surface activity of smectite clays in catalysis and adsorption.
Document ID
19800051894
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Banin, A.
Rishpon, J. (Jerusalem, Hebrew University Rehovot, Israel)
Date Acquired
August 10, 2013
Publication Date
December 1, 1979
Publication Information
Publication: Journal of Molecular Evolution
Volume: 14
Subject Category
LUNAR AND PLANETARY EXPLORATION
Funding Number(s)
CONTRACT_GRANT: NCA2-OR-660-704
CONTRACT_GRANT: NSG-7512
Distribution Limits
Public
Copyright
Other