Characterization of microbialites and microbial mats of the Laguna Negra hypersaline lake (Puna of Catamarca, Argentina)

BOIDI, F.J.; MLEWSKI, C; GOMEZ, F.J.; GERARD, E.

Microbial Ecosystems in Central Andes Extreme Environments

Springer

Año: 2020;

Microbial carbonates provide an invaluable tool to understand biogeochemical processes in aqueous systems, especially in lacustrine and marine environments. Lakes are strongly sensitive to climatically-driven environmental changes and microbialites have recently shown to provide a record of these changes. Unraveling physicochemical and microbiological controls on carbonates textures and geochemistry is necessary to correctly interpret these signals and the microbial biosphere record within sedimentary carbonates. The Laguna Negra is a high-altitude hypersaline Andean lake (Puna of Catamarca, Argentina), where abundant carbonate precipitation takes place and makes this system an interesting example that preserves a spectrum of carbonate fabrics that reflect complex physical, chemical, and biological interactions. The extreme environmental conditions (high UV radiation, elevated salinity, and temperature extremes) make the Laguna Negra a good analogue to some Precambrian microbialites (e.g., Tumbiana Fm., Archean, Australia). In addition, the discovery of ancient evaporating playa-lake systems on Mars surface (e.g., ShalbatanaVallis, Noachian, Mars) highlights the potential of Laguna Negra to provide insight into biosignature preservation in similar environments. Given that microbial processes in the Laguna Negra can be studied with remarkable detail, this may provide insight into biosignature preservation in both, terrestrial and extraterrestrial settings.