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Searching for Silicate Bioweathering on Earth and Mars. Martin Fisk, Oregon State University Michael Storrie-Lombardi, Kinohi Institute contributors Radu Popa, Portland State University Olivia Mason, Oregon State University Ed Vicenzi, Smithsonian Institution. Abiotic. Glass. Biotic.
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Searching for Silicate Bioweathering on Earth and Mars Martin Fisk, Oregon State University Michael Storrie-Lombardi, Kinohi Institute contributors Radu Popa, Portland State University Olivia Mason, Oregon State University Ed Vicenzi, Smithsonian Institution
Abiotic Glass Biotic (Sans Expert) Probabilistic Classification of Biotic Alteration in Basalts Elemental Abundance Signatures for Abiotic & Biotic Alteration of Ocean Basalts [Na, Mg, Al, Si, P, Cl, K, Ca, Ti, Mn, & Fe] PCA ANN Storrie-Lombardi, M. C. and Fisk, M. R. (2004) Elemental abundances in sub-ocean basalt glass and secondary minerals: evidence of biotic and abiotic alteration Geochem., Geophys., and Geosys. 5 (10), doi:10.1029/2004GC000755.
Oregon Dunite with microbial galleries and DNA fluorescence
Fisk, M.R, Popa, R., Mason, O.U., Storrie-Lombardi, M.C., and Vicenzi, E. 2006, Iron-Magnesium Silicate Bioweathering on Earth (and Mars?), Astrobiology, 6 (1), p. 48-68.
Observations in a Martian Meteorite Nakhla Nakhla
Why Choose an Ancient Igneous Rock Site? Provides information on earliest volcanism on the planet. Provides a record to test the hypothesis of early aqueous alteration. Igneous rocks preserve evidence of life for billions of years. Biosignature in igneous rocks can incorporate but do not depend on the presence of classical organic constituents [ H, C, O, N, P]. Biosignatures in igneous rocks are amenable to automated pattern recognition techniques. Igneous rock sites are dry and comply with planetary protection constraints. Multiple sites exist (many already well-surveyed) exhibiting low altitude, low latitude, minimal slope, and minimal wind characteristics.
Ideal Igneous Site Mandatory • Exposed Noachian igneous rocks. Excellent if • Prolonged exposure to water • Dry ever since for preservation. Ideally • “Go to” availability of sulfates and layered terrain And of course • Surveyed by MOC, MOLA, TES, THEMIS, HSRC, and OMEGA and targeted by MRO/CRISM. • Optimize engineering constraints for wind, altitude, latitude, and slope.
What Site? Site Location Altitude Proponent (km) NE Syrtis Major 10oN 70oE 0.5-1.5 Harvey Nili Fossae 22oN 75oE -0.6 Mustard Marwth Vallis 22.3oN 343.5oE -2 Bibring Eos Chasma 10.9oS 321.7oE -4.1 Hamilton