Microbialite Niches Across the Archean and Paleoproterozoic

Abstract Changes in microbialite abundance during the Archean and Paleoproterozoic have been attributed to a variety of environmental and biological factors, yet past work looking at large‐scale patterns of microbialite abundance generally assumes shallow marine deposition rather than incorporating specific settings. We compiled Archean and Paleoproterozoic microbialite occurrences and depositional environment information to assess how microbialite development and preservation changed across settings. Microbially induced sedimentary structures formed a significant part of the record, but may be undercounted as they were identified mostly in units that also contained stromatolites. While broad trends in abundance resembled previous compilations, critically, we found that more microbialites formed in tidal environments than subtidal marine. The proportion of terrestrially influenced (including tidal) microbialites peaked during periods of craton development and following the Great Oxidation Event and Huronian Glaciations. These findings highlight the importance of continental landmasses and tectonic processes in defining the distribution and preservation of early life.