Microbial Biosignatures in Iron-Mineralized Phototrophic Mats at Chocolate Pots Hot Springs, Yellowstone National Park, United States

Research at Yellowstone National Park's Chocolate Pots hot springs reveals that iron permineralization can produce exceptionally well-preserved microfossils, challenging the long-held assumption that silica is required for high-fidelity fossil preservation. The study documents how phototrophic iron-oxidizing microbial communities form distinct biosignatures, including dendritic-like biofabrics and identifiable microfossils, preserved by 2-line ferrihydrite. By integrating microscopy, X-ray diffraction, spectroscopy, and elemental analysis, the authors link microbial physiology to biosignature formation, offering a new framework for interpreting ancient iron deposits. This work provides critical insights into the paleobiology of Precambrian iron formations, bridging modern microbial processes with deep-time geological records.

PARENTEAU, M. N., & CADY, S. L. (2010). MICROBIAL BIOSIGNATURES IN IRON-MINERALIZED PHOTOTROPHIC MATS AT CHOCOLATE POTS HOT SPRINGS, YELLOWSTONE NATIONAL PARK, UNITED STATES. Palaios, 25(2), 97–111. https://doi.org/10.2110/palo.2008.p08-133r