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Background Photo: Betsy Kleba (Microbiologist from Westminster College) and Brenda Bowen (Geologist from University of Utah) work with undergraduate students at the Bonneville Salt Flats, UT to explore the microbial ecology and geochemistry of this dynamic and extreme environment.

UT

ScPIs: Betsy Kleba and Brenda B. Bowen

We hypothesize that there is a diverse microbial community inhabiting the various strata of the Bonneville Salt Flats salt crust and that there are spatial variations in their abundance and/or diversity related to chemical and compositional variations in the salt sediments. Work to date by the geoscience team (Bowen and students) has focused on identifying stratigraphic variations in salt crust composition. We have identified seven different distinct strata types based on texture and composition. Mineralogical and geochemical differences are characterized with visible-near infrared reflectance spectroscopy, X-ray diffraction, and X-ray fluorescence. Salt crust strata include varying amounts of halite (NaCl), gypsum (CaSO4(H2O)2), trona (Na3H(CO3)2.2H2O), calcite & aragonite (CaCO3), and phyllosilicate clays including montmorillonite ((Na,Ca) (Al,Mg)2(Si4O10)(OH)2•nH2O) and illite (K,H3O)(Al,Mg,Fe)2(Si,Al) 4O10[(OH)2,(H2O)]), as well as black, green, and orange organic matter. The microbiology team (Kleba and students) is using fluorescence microscopy and culture-dependent techniques to demonstrate the existence of microbial life within each layer and to calculate cell densities. We have documented the presence of viable cells within all subsurface strata tested to date. Moreover, preliminary data indicate that cell density varies between layers suggesting a dynamic microbial community inhabits the crust. We are now using molecular tools to characterize microbial community composition within each layer. This information will be paired with geochemical and mineralogical data as a first step toward examining the relationship that exists between microbial life and chemical composition of the strata of the Bonneville Salt Flats salt crust. Results from this project will inform our understanding of habitable zones within evaporite systems- information with the potential to influence the search for life or biosignatures on other planetary bodies. www.nasa.gov/epscor/stimuli

Geomicrobiology of the Bonneville Salt Flats: Interdisciplinary astrobiological characterization of microbial and geologic relationships in an extreme earth environment.

Rydge Mulford and Brian Iverson examining the blackbody cavity and heat flux probes used to provide radiative heating.

NASA EPSCoR Stimuli 2014-15

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EPSCoR Stimuli 2014-15  

NASA Office of Education’s Aerospace Research & Career Development (ARCD) is pleased to release NASA EPSCoR Stimuli, a collection of univers...

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