Iron Enrichment by Biological Iron Oxidation and Reduction in Microbial Mats of the Paleoarchean Moodies Group
MetadataShow full item record
Although life has existed on earth for at least 3.8 billion years, biogeochemical ‘fossils’ left behind by microbial life before the Great Oxygenation Event are contentious. The Mars 2020 rover will target Noachian age sites that show potential for once having harbored life, therefore it is essential that geochemical biosignatures capable of peering back into deep time be developed. In this experiment, μXRF, petrography, handheld XRF, and statistical analysis were utilized to examine if crinkled laminae within the Moodies Group tidalites contained geochemical biosignatures that would be both diagnostic of specific biological processes, and broadly applicable in similar rocks. A diagnostic proof of life, specifically of a complex iron cycling ecosystem, was found within the rocks, currently expressed as regions of chamositic clay deposition limited to areas within ‘crinkled’ laminae suspected of being the remnants of ancient microbial mats.
Neal, Charles Francis (2018). Iron Enrichment by Biological Iron Oxidation and Reduction in Microbial Mats of the Paleoarchean Moodies Group. Master's thesis, Texas A & M University. Available electronically from