Nanoscale characterization of mineral self-organized membranes in anoxic conditions: implications for the origin of life and life detection

Self-organized, iron-silica(te) membranes might have served as redox catalysts in the early Earth hydrothermal systems proposed as niches for the emergence of metabolism. Moreover, they have similar morphologies and composition to biologic iron filaments found in silica-rich rocks, including those considered the oldest on Earth. Yet, available information on the mineralogy of these nanocomposite membranes comes from experiments-analyses performed in presence of oxygen. To investigate their formation and composition in anoxic conditions that were prevailing in early Earth, we will perform the their growth in capillaries inside a glovebox chamber and characterize them at the nanoscale using high-energy X-ray scattering experiments, combined with PDF analysis, while maintaining them in inert atmosphere. These results will advance our knowledge on early Earth mineralogy, the catalytic role of such membranes in prebiotic chemistry and the recognition of traces of life in the rock record.