22-EPN3-087: Evolution and Icy Satellite Deformation through the Investigation of Glacial Environments and the Characterisation of Earth Analogues

22-EPN3-087: EVIDENCE – EVolution and Icy satellite Deformation through the investigation of glacial ENvironments and the Characterisation of Earth Analogues

Visit by Costanza Rossi (INAF-Astronomical Observatory of Padova, Italy) and Riccardo Pozzobon (University of Padova) to TA1.6 Argentinian Andes (Argentina).
Dates of visit: 20 February – 01 March 2024

Report Summary: The Tierra del Fuego glaciers in Patagonia (Argentina) represent optimal analogues for the study of the deformation of icy planetary surfaces, and in particular those of Jupiter and Saturn icy satellites. The multi-scalar approach of the EVIDENCE project addresses to the relation of the glacier’s deformation structures from local-scale to regional-scale. Such investigation provides pivotal support for planetary analysis, to better understand the expected local-scale structural pattern. Through the fieldwork in the Tierra del Fuego glaciers, scaling laws of deformation in icy surfaces have been identified from the tectonic setting at local-scale at both surface and depth.

The fieldwork in the Ushuaia area has allowed the identification of structures (fractures/faults) in Vinciguerra, Martial, Ojo del Albino and Alvear glaciers and in the Cueva del Jimbo. Field data have been acquired by UAV detection and structural geology survey and integrated in virtual outcrop models. Both high-angle extensional and strike structures and low-angle thrusts have been recognised at local-scale. Such data will be then compared with the structures visible on regional-scale satellite images of the investigated glaciers. This comparison will allow to understand analogies and differences of the structural pattern between the investigation scales and to gain knowledge that will be in turn applied to the regional-scale data of analogue areas in the surfaces of the icy satellites. In addition, structural measurements in bedrock outcrops surrounding the glaciers have been performed to understand the relationship between the underlying bedrock tectonics and glacial deformation.

21-EPN-FT1-003: Biogeochemical tools to search for biosignatures in microbial carbonates from extreme environments

21-EPN-FT1-003: Biogeochemical tools to search for biosignatures in microbial carbonates from extreme environments

Visit by Sylvie Bruggmann, University of Lausanne (Switzerland) and Camila Areias, Vrije Universiteit Amsterdam (Netherlands), to TA1.6 Argentinian Andes (Argentina).
Dates of visit: 10-16 December 2022

Report Summary: Microorganisms evolved under extreme conditions as the first forms of life on Earth. In the geological record, signatures of these microbial communities can be preserved in the chemistry of sedimentary rocks as microbialites. The identification of their biogenicity, however, is often ambiguous, as biosignatures can be overprinted, and abiotic processes may form similar signatures. Microbialites forming under extreme conditions on the modern Earth can be used as analogues to better understand the formation of biosignatures, and to improve their identification in sedimentary rocks from Earth and Mars.

The TA1 Facility 6 in the Argentinian Andes provides an ideal environment where carbonaceous microbialites form under extreme conditions, such as cold temperatures, low precipitation and high UV radiation. To better resolve the ambiguity of biosignatures, we use a combined approach of organic and inorganic biogeochemical tools to examine sediment and water samples. The organic tool focuses on lipid biomarkers that can be attributed to specific biogenic sources, such as cyanobacteria. In addition, the inorganic tool utilises elemental concentration and isotope compositions of biologically relevant metals, such as Fe or Sr, which can record information of a biogenic or abiotic origin. The combination of these organic and inorganic tools can improve the identification of biosignatures and their credibility can be enhanced.

21-EPN-FT1-018: Assessing analogues to early Earth environmental conditions in high-altitude hypersaline Andean lakes

21-EPN-FT1-018: Biogeochemistry in extreme environments: assessing analogues to early Earth environmental conditions in high-altitude hypersaline Andean lakes

Visit by Alexandra Rodler, Austrian Academy of Sciences (Austria) to TA1.6 Argentinia Andes (Argentina).
Dates of visit: 11-16 December 2022

Microbial activity leaves fingerprints in the sedimentary record, for example, by changes in trace element and isotope ratios. If distinguishable from purely abiotic processes, these traces can potentially be used as biosignatures for geobiological and astrobiological research. Modern analogue environments are useful for better understanding traces of microbial life in the geologic record. This can help to define search criteria for potentially habitable environments on other terrestrial planets. The test site for this project is the Precambrian-analogue TA1 Facility 6 in the Argentinian Andes. This is a shallow lake system with extensive microbial mats, hypersaline conditions at slight acidity, with extreme temperature fluctuations and high-UV ray influx.

Using samples from this site, this project compares between chemically- and microbially influenced carbonate precipitation to further explore if trace element behaviour is related to biological processes, and if specific elements can be used as potential biosignatures. Furthermore, this project investigates trace element behaviour along redox gradients between hydrogenetic and diagenetic microbialite growth. To address if certain elements can serve as biosignatures, we pair petrographic/mineralogical approaches with high-resolution sampling for analysing trace elements as well as redox-sensitive elements and their stable isotopes. The results of this work are integrated in ongoing work focused on the geochemistry of carbonate phases of modern and ancient microbialites as well as the ongoing microbiological work including microbial diversity and metagenomics at this site. This ensures that the results are integrated in and compatible with these diverse fields of research.

21-EPN-FT1-026: Biogeochemical cycling in the lake systems of the Argentinian Puna

21-EPN-FT1-026: Biogeochemical cycling in the lake systems of the Argentinian Puna: An investigation into the microbial communities of an exceptional Hesperian martian analogue

Visit by Ben Tatton, The Open University (UK) to TA1.6 Argentinian Andes (Argentina).
Dates of visit: 17-26 April 2022

Report Summary: Fieldwork undertaken as part of the Europlanet fast track funding call took place between 16/04/22 and 26/04/22 as part of an international team of scientists from The Open University, The Università degli Studi della Tuscia, and The Universidad Nacional de Córdoba.

Fieldwork was conducted at two high-altitude Andean Lake (HAAL) sites, Laguna Negra, and Laguna de Antofagasta. The focus of the research was to collect sediment cores and water samples from Laguna de Antofagasta to assess how microbial communities change as a factor of depth within the sediment. During the trip, a total of 5 x 30 cm cores, 5 x 250 ml of lake water for culturing, and 15 x lake water samples for geochemical analysis were collected. Furthermore, environmental variables were taken with pH, temperature, conductivity, redox potential, and UV monitored. The trip was a resounding success with enough samples taken to permit the progression of my PhD. The data gained from the trip will contribute to two or three data chapters. These chapters will focus on the geochemical characterisation of the site, the microbiology of the site, and potentially simulation experiments which will focus on Noachian/Hesperian Mars relevant metabolisms. We expect to find that LDA is a suitable geochemical analogue for Gale Crater during the Noachian Hesperian transition. We also expect that the types of metabolisms found within the sediments are similar to those predicted to have been present on Noachian/Hesperian Mars.