Biosignature Preservation in Sulfate-Dominated Hypersaline Environments

Introduction: Observations of Mars have revealed the existence of ephemeral paleolakes, today represented by widespread deposits of sulfate salts. Salts have long been documented as being capable of preserving a rich record of biological processes, having obvious implications for the search for life on Mars. Much of the work into biosignature preservation in hypersaline environments on Earth has focused on NaCl-rich systems, owing to the dominance of this salt type. MgSO4 systems, alternatively, are of interest given the stabilizing nature of the sulfate anion for biological molecules. Ongoing investigations into a range of sulfate deposits have revealed the preservation of DNA, amino acids, and cells on timescales of thousands to millions of years. Here we investigate the sulfate-dominated systems of the Basque Lakes, Clinton Lake and Last Chance Lake, in British Columbia, Canada and explore the preservation potential of these salts for (geologically-speaking) short-term and long-term biosignatures. Work will be conducted in the summer and winter months, sampling salt crusts, the water column, and the sediment. This builds on work that our group has previously conducted at Spotted Lake in BC.