20-EPN-FT1-024: Untangling rock-inhabiting microorganisms and their biosignatures from the Mars-like area of Puna Plateau, Argentinian Andes
Visit by Lorenzo Aureli and Gerardo Antonio Stoppiello, University of Tuscia (Italy), to TA1.6 Argentinian Andes (Argentina).
Dates of visit: 17-23 April 2022
Report Summary: The hostile current conditions on the surface of Mars entail that, if any form of life exists or ever existed on the planet, it may have adopted survival strategies like those evolved by terrestrial microorganisms inhabiting extremely harsh regions. Here, one of the most common strategies observed is endolithic growth, defined as the colonisation of the small interstices and cracks inside rocks where microorganisms can be protected from external hostile conditions. On the other hand, environments exhibiting a strong negative hydrological balance can be characterised by the sporadic presence of pools saturated in minerals. Here, microorganisms can induce carbonate precipitation along with the physicochemical factors occurring in these environments, causing the formation of sedimentary structures in which they can be trapped.
From an astrobiological perspective, several studies showed how the early Mars environment may have exhibited an overall desertic environment hosting localised water basins. Therefore, the possibility that microbial forms of life may have existed on Mars makes hypothetical endolithic habitats and evaporite deposits on the planet interesting targets for the search for tracks of past life. In this optic, the southern end of the Puna Plateau in the Argentinian Andes (Catamarca province, Argentina) may represent an excellent model to understand how putative microorganisms may be adapted to the early Martian environments and how to detect their signatures. For this reason, a sampling campaign was performed at the Laguna Negra Lake (Puna Plateau region) in April 2022, with the purpose to characterise different microbial habitats hosted in the site.
Read the full scientific report, with kind permission by Lorenzo Aureli.