Biosignature Preservation Potential Among Diverse Calcium Sulfate Textures from the Atacama Desert, Chile

Calcium sulfate minerals are widespread on both Earth and Mars and have the capacity to preserve evidence of life over geological timescales. Many distinct textural varieties of sulfate minerals occur and, depending on their depositional environment and diagenetic history, each may offer distinct pathways for biosignature preservation (i.e., “taphonomic windows”). However, these processes remain underexplored due to the high solubility of sulfates and, hence, their relative scarcity in the earliest rock record. Here, we explore the potential to preserve remnants of microbial life including carbonaceous microstructures resembling known organisms, as well as biomarkers preserved in the intracrystalline sulfate matrix.