22-EPN3-007: SeisChem – The influence of seismic events on fluid and gas chemistry at the Icelandic planetary field site

Visit by John Edgar and Jon Telling (Newcastle University, UK) to TA1 – Iceland Field Sites, MATIS
Dates of visit: 12-21 September 2023

Measurable H₂ can be generated during active seismicity through the reaction of water with freshly created rock surfaces. Field measurements have shown that rock-water reactions during seismic events can also lead to significant changes in the pH and increase the concentration of H₂O₂ in geological fluids. Whilst prior studies have investigated locations representing felsic crust, a large proportion of the deep biosphere resides in basaltic terrains. H₂O₂ generated through rock-water reactions is greater in basaltic rocks and enhanced when temperatures exceed ~80 °C. Importantly, these elevated temperatures overlap the growth ranges of some hyperthermophilic microorganisms. The generation of H₂O₂ in these environments represents an understudied energetic window of opportunity for extant microbial life, and possibly for the origins of life on Earth.

This project sampled a seismically active hydrothermal area in Iceland where elevated temperatures were anticipated to lead to enhanced H₂O₂ generation from rock-water reactions.
The SeisChem team investigated the relationship between seismicity and the products of rock – water reactions in a geologically active hydrothermal system. The central objective of SeisChem was to bridge a knowledge gap between laboratory studies and field measurements by:

• Sample fluid and gas in time series, recording in-situ H₂O₂ and ancillary geochemical data
• Store and return samples to the laboratory for H₂ (g) and major ion (aq) analyses
• Compare and contrast field and laboratory data with local seismic activity.

Read the full scientific report with kind permission by John Edgar and Jon Telling.

22-EPN3-130: Biosignatures in Icelandic geothermal aerosols

Visit by Mark Fox-Powell and Ben Stephens (Open University, UK) to TA1 – Iceland Field Sites, MATIS
Dates of visit: 23-31 August 2023

The aim of our project was to capture and study microscopic aerosols ejected from bubbling geothermal springs in Iceland, as an analogue for the formation of cryovolcanic plumes at icy moons such as Enceladus. This project built on a successful Europlanet-funded field campaign in 2022. Our objectives in 2023 were to (i) comprehensively map size-dependent aerosol fluxes with increasing distance and elevation from the springs; and (ii) to collect simultaneous samples for microbiological and elemental analyses at multiple downwind locations.

We focused our investigations on Olkelduhals hot springs, near Hverageroi, where a pool with circum-neutral pH supporting thick microbial streamers experiences constant moderate gas flux. Our data from 2022 showed that this spring is a prolific and constant source of aerosols. We found that downwind aerosol size distributions changed with distance and with elevation from the spring. Four complete aerosol sample sets were taken downwind of the spring; each requiring a full field day. A background (upwind) air sample was also taken. Comprehensive samples for geochemical and microbiological analyses were taken from the spring, along with the collection of volatile and semi-volatile organic compounds using thermal desorption tubes. The sample set will form the basis of a new PhD studentship, beginning in October 2023 at the Open University, which will investigate the chemical composition, biomass content and microbial diversity of aerosols, and the volatile profiles of geothermal gases. Our data will provide the first insights from natural analogues into the formation of aerosols within cryovolcanic plumes.

22-EPN3-116: Fault Scaling at Southwest Iceland

Visit by Işık Su Yazıcı (German Aerospace Center DLR, Germany) and Sebastian Sturm (University of Freiburg, Germany) to TA1 – Iceland Field Sites, MATIS
Dates of visit: 02-10 August 2023

Fault population studies reveal the lithospheric stress and strength conditions. Geometric fault properties provide insights into mechanical and temporal evolution of fault systems, as well as past and future potential for seismic energy release. Understanding the displacement-length relationship of faults can also help to estimate the current seismicity level. Improved constraints on the current seismicity of Mars based on lnSight mission results, are the motivation for a renewed and detailed analysis of martian fault systems. Partly due to the limited number of reliable datasets, data on the relationships between fault displacement and length of extraterrestrial bodies are scarce. Using Digital Elevation Models (OEM) and corresponding orthoimages derived from High Resolution Stereo Camera (HRSC) data, we previously obtained information on the displacement distribution along faults and the maximum displacement (Dmax) at the Memnonia Fossae (MF) fault system on Mars.

The volcanic rifting zone in SW Iceland displays similar characteristics as MF. Specifically, the availability of airborne HRSC data (HRSC-AX) of an area characterized by widespread normal faults in the rift zone at Thingvellir, and well-exposed faults in Reykjanes, are exceptionally well-suited sites as analogues for the MF. Considering the scarcity of terrestrial analogue work complementing the analysis of planetary fault scaling, this field work helps to improve our understanding of fault scaling relationships: Our goal is to combine terrestrial remote sensing data (HRSC-AX) with ground truth to obtain a better basis for evaluating planetary fault scaling (which relies on remote sensing only).

Read the full scientific report with kind permission by Işık Su Yazıcı.

22-EPN3-061: Analogue Studies to Test the Scientific Potential of the First SERS Prototype Analysis

Marco Veneranda and Guillermo Lopez-Reyes (University of Valladolid, Spain) to TA1 – Iceland Field Sites, MATIS
Dates of visit: 24-30 July 2023

Iceland provides access to a great variety of environments that are widely considered potential analogues of hydrothermal processes on Mars). Previous investigation revealed a wide variety of microbial communities proliferating at the water side of Krysuvik and Hveradalir hydrothermal systems. Although providing crucial information on the dynamics of extremophilic life, the lack of low altered mineralogical samples prevented from: 1) fully comprehend the hydrothermal weathering dynamics of the primary rock (extrusive Fe-rich basaltic lava), and 2) determine the relation between microbial proliferation and the degree of hydrothermal alteration of the hosting mineral substrate. 

As these two aspects are of key importance to understand the habitability potential of the ancient hydrothermal systems found on Mars, Marco Veneranda and Guillermo Lopez Reyes performed a new campaign of analysis to address these two topics. On one hand, the two researchers investigated the mineralogical composition of the two analogue sites by using a portable emulator of the RLS Raman spectrometer onboard the ESA/ExoMars rover. Afterwards, a novel device for the automated synthesis of SERS nanoemulsions was used to investigate the organic content of the hydrothermal waters. The obtained results were then used to select optimal geological and biological samples to be returned in the laboratory for further investigation. As a whole, this research project aims at supporting the RLS team in defining and optimizing the potential scientific outcome of the RLS instrument once it will be operated on the surface of Mars.

Read the full scientific report with kind permission by Marco Veneranda and Guillermo Lopez-Reyes.

22-EPN3-011: Phototrophic Microorganisms in Cold Deserts of Iceland – Ecology and Diversity of Potential Analogues

Visit by Daniel Remias (University of Salzburg, Austria) and Lenka Procházková (Charles University, Czech Republic) to TA1 – Iceland Field Sites, MATIS
Dates of visit: 07-13 July 2023

Geology and climate of inland regions at Iceland are ideal prerequisites for exploring microbial adaptation to cold and dry habitats. Bare terrestrial ground surfaces and high­altitude melting snowfields represent niches at the edge of life on Earth. Soil samples were harvested at altitudes from almost at sea level up to more than 1000 m. Additionally, red snow caused by cryoflora (snow algae) from permanent snow packs in the Kerlingarfjoll Mountains were collected, and photosynthetic uptake rates were measured in situ with labelled carbon (¹³C). Red snow was transported to the lab and the pigments extracted and the UV-protecting pigments characterized by HPLC.

The main aim of the project was the molecular characterisation of the phototrophic microbial community for evaluation of abundance and diversity of terrestrial and frozen habitats. Barren, desert­like sites were compared with vegetated ones. Microalgae marker DNA were extracted with dedicated kits for environmental soil samples.

This study aims to shed light on how photoautotrophic microbial life could work at Earth analogues with similar or even worse climatical or soil conditions. Finally, Icelandic terrestrial microalgae will be tested as potential analogues compared to other worlds like Mars or icy moons.

Read the full scientific report with kind permission by Daniel Remias and Lenka Procházková.

Image credit: Desert-like sampling site close to Sandfell Mt. Credit: D Remias.

22-EPN3-060: A new apparatus for measuring the electrical charge of volcanic ash particles

Visit by Allan Fries, University of Geneva (Switzerland), to TA2.4 Planetary Environment Facilities (PEF), AU (Denmark)
Dates of visit: 02-11 August 2023

Report summary: The electrical charge carried by volcanic ash particles is known to play a crucial role in the formation of aggregates, which modulate the atmospheric transport and deposition rate of volcanic ash. However, direct field measurements of these charges remain rare, and more investigations are required to better comprehend both charge generation and aggregation mechanisms. This study aimed at building and testing a portable device to quantify the charge of individual volcanic ash particles and aggregates using a Through-Type Faraday Cage (TTFC) connected to a charge amplifier circuit capable of detecting the very small voltages induced by charged particles entering the TTFC.

After building the apparatus, 187 tests were performed, using different quantities and types of particles, as well as varying the measurement technique. First results show that the newly built device is capable of measuring charges down to 0.1 pC and that measurements agree well with alternative estimations obtained by directly integrating the current generated in the TTFC over time.

Beside the charge, results also suggest that the device can be used to obtain the particle settling velocity, based on the duration of the voltage signal. Few additionnal tests are now required to detect smaller particles (i.e., smaller charges) and the instrument will then be used for field analysis and laboratory experiments.

Read the full scientific report, with kind permission from Allan Fries.

22-EPN3-061: CO₂ Ice Crystals Formation Under Conditions in the Martian Polar Regions: Influence of Substrate Properties and Temperature Gradient

Visit by Ganna Portyankina, DLR (Germany), to TA2.4 Planetary Environment Facilities (PEF), AU (Denmark)
Dates of visit: 30 April – 01 October 2023 (two visits)

Report summary: The main goal of most recent tests conducted at the Planetary Environment Facilities at Aarhus University was to condense CO₂ from the chamber’s atmosphere under Martian conditions onto a specially designed set of different surface materials (martian regolith simulant, glass beads of various sizes, dust). We investigated ranges of temperatures and pressures and observed the texture of the created CO₂ ice. Our goal was to determine if CO₂ deposits over regolith/glass beads/dust differently compared to brushed aluminium. We have observed that various properties of substrate did not considerably alter the deposition morphologies of CO₂ observed in our previous work. Most importantly, we find that under conditions usual for Martian polar areas in fall and winter, CO₂ ice always deposits as a translucent slab.  Under deviating conditions, i.e. colder temperatures and lower pressures, CO₂crystals assume different shapes including opaque slab and highly porous multi-crystalline. Such CO₂crystalline morphologies require further investigations, because of their relevance to icy satellite surfaces as well as CO₂ cloud formation.

Read the full scientific report, with kind permission from Ganna Portyankina.

21-EPN-FT1-012: Zebra dolomites revised: clumped isotope analysis as a tool to assess recrystallisation and dolomite cementation in overpressured settings

Visit by Swennen Rudy, KU Leuven (Belgium), to TA2 Facility 17 – Isotoptech Stable/Clumped Isotopes Laboratory (Hungary).
Dates of visit: 22-26 May 2023.

Report Summary: Zebra dolomites are marked by an alternation of millimeter thick dark colored, as recrystallised interpreted bands and white cement bands. Disruption of the banding is manifested by displacements that gradually increases and subsequently deceases before disappearing. This disruption also occurs at intracrystalline scale with crystal rehealing features as observable under cathodoluminescence. This disruption of the zebra dolomites is explained by dolomitization in relation to overpressured fluid flow.  

In the framework of the Europlanet project zebra dolomite samples from 3 deep Belgian boreholes (Soumagne, Soiron and Bolland) were selected for clumped isotope analysis.  The aim was to sample and analyse the dark fine crystalline and white coarse dolomite cements separately to infer the original (re)crystallization temperature.  The following research questions were raised: i) is there a systematic difference in deduced temperature between the dark and white dolomite bands.  If so then this could help to better constrain the recrystallisation and cementation.  This would allow to assess the potential resetting of the original clumped isotope signature of the dark bands due to recrystallisation; ii) if the cement phases display uniform temperatures then this temperature can be compared with the minimum crystallization temperature deduced from primary fluid inclusion microthermometry [1]. The discrepancy between both temperatures, which links to the pressure correction, normally allows to quantify the overpressure of the system; iii) based on deduced crystallization temperature and δ¹⁸O_PDB, the δ¹⁸O_SMOW of the fluid can be assessed, allowing to constrain the origin of the dolomitizing fluids, certainly when combined with Sr isotope analysis.

22-EPN3-128: Northwestern Amazon regional convection and its role in the control of extreme events and the isotopic signal in Quito, Ecuador.

Visit by Maria Sheila Fabiola Serrano Vincenti, Universidad Politécnica Salesiana (Ecuador), to TA2 Facility 17 – Isotoptech Stable/Clumped Isotopes Laboratory (Hungary).
Dates of visit: 22-26 May 2023.

Report Summary: The goal of the 2023 visit to the TA Facility was to measure rainwater δ2H and δ18O values sampled at daily and monthly resolution from October 2022 to May 2023 in three different monitoring sites at North, South and Valley sites in Quito-Ecuador. Due to the complex orography, the sites experience varying intensities of rainfall and hailstorms. These measurements are part of a project aiming to understand the dynamical processes that contribute to the observed heavy and extreme precipitation events in the Tropical Andes, specifically in Quito.

Understanding these isotopic data will help the interpretation of the variations in δ²H and δ¹⁸O during intense rainfall events and subsequent fractionation due to local and upstream convection, orographic lift and moisture recycling. In addition to the measured isotopic signals, rainfall amount, pH, conductivity, and Total Dissolved Solids (TDS) data will be statistically analysed from the sites. Similarly, instrumental daily precipitation and cloud coverage information from instrumental and satellite data will be examined for convective rainfall (thunderstorms) and moisture provenance characterisation.

Read the full scientific report with kind permission by Sheila Serrano-Vincenti.

22-EPN3-086: Exploring the Effects of H+, On+, and Sn+ Irradiation of Water Ice, plus an ISM relevant Molecule, as a Potential Prebiotic Europa Ocean Analogue

Visit by Alexandra Corrigan, University of Kent (UK) to TA2.12 Atomki-Queen’s University Ice Laboratory for Astrochemistry (Hungary).
Dates of visit: 15 May – 06 June 2023

Report Summary: At the AQUILA chamber in the ECRIS Laboratory at the Atomki Institute for Nuclear Research the effects of H⁺, O²⁺, and S⁵⁺ irradiation of water ice, plus Formamide, as a potential prebiotic Europa ocean analogue were explored. Three sodium chloride windows, covered with a 1:1 ice mixture of water and Formamide, were irradiated with ion beams. The windows were cooled down to 90K in vacuum, and a 200-250 nm thick ice layer was deposited at them. In the first experiment, the sample was irradiated using a 15keV H⁺ ion beam in 12 steps, up to a total fluence of 1.1x 10¹⁵ ion/cm². After each irradiation steps an infra-red (IR) spectrum was taken to observe the irradiation products. After completing, the sample was warmed up to 300K in 30K increments, taking an IR spectrum at each interval. During both irradiation and heating, the sputtered molecules were monitored by QMS. Finally, after a full warming up of the cold parts we opened the chamber, removed the sample (for post-TA residue analysis using LCMS/MS), replaced the NaCl window, and pumped the chamber. This protocol was repeated (with different irradiation fluences) for 30keV O²⁺ and 60keV S⁵⁺ ion beams. All the sample windows have been taken for residue analysis. From initial analysis of the spectra it seems that the Formamide was broken, and formed products such as CO, CO₂, OCN^–, and CN^–. Further investigation is required to confirm these results and to determine what other products were created during the irradiation. 

22-EPN3-088: Scrutinising bio- and geo-signatures in support of the Raman interpretation of space missions data

Visit by Ana de Dios Cubillas, CSIC-INTA (Spain) to TA2.19 Center for Microbial Life Detection, Medical University Graz (Austria).
Dates of visit:17 – 28 April 2023

Report Summary: This project is devoted to investigate geo- and biosignatures that can be preserved in mineral assemblages formed in extreme aqueous terrestrial environments. Environments such as subaerial hot springs that could had existed on early Mars, and cold-seep marine environments that can develop in icy-moon oceans are particularly interesting for astrobiology. In order to achieve this goal, we use information obtained by Raman spectroscopy and SEM/EDX microscopy.

Raman spectroscopy is a recently incorporated analytical technique in the payload of several space missions: SHERLOC@Perseverance, Supercam@Perseverance, RLS@ExoMars and RAX@MMX. It is based on the scattering effect generated by the interaction of photons with the electron density of the chemical bond of a molecule. The position and width of the Raman bands give information on the structure, chemical and isotopic composition and crystallinity of mineral. Studying changes in Raman frequencies allows to evaluate the biological or inorganic origin of the sample. This methodology is relevant for the in-situ identification of geo- and bio-signatures in soil/rock samples collected during space missions.

Several bio-mediated minerals sampled from several hydrothermal and cold-seep areas were characterised by micro-Raman spectroscopy coupled with scanning electron microscopy (SEM/EDX). Obtained Raman spectrum was correlated with its texture in order to identify patterns that would allow us to assess the biological or inorganic origin. We observed Raman band shifting and width changes. These results should be complemented by further experimental work to determine the involvement of bio-mediation processes.

Read the full scientific report, with kind permission by Ana de Dios Cubillas.

22-EPN3-107: Characterising the electron-impact-induced emission of CS2 to constrain sulfur abundances in cometary and planetary atmospheres

Visit by Steven Bromley, Auburn University (USA), to TA2 Facility 13 – Electron Induced Fluorescence Laboratory (Slovakia).
Dates of visit: 08 – 19 May 2023

The main goals of the 2023 visit were to study the electron impact emission cross sections, spectral features, and dissociation thresholds of CS₂ gas. The products of CS₂ – atomic sulfur and its ions, CS, excited CS₂, and CS₂⁺ – make CS₂ a rich target of inquiry. Further, the products CS and atomic S are routinely observed in near-nucleus observations of comets (see e.g. discussion in Noonan et al. 2023). Measurements of sulfur abundances in comets show discrepancies between remote and in-situ observations, and improved electron-impact data for CS₂ may help resolve this discrepancy. The present experiments are part of a long-term campaign to understand diagnostic electron-impact driven emission and ionization of diatomic/polyatomic molecules in cometary atmospheres. We expect these data will provide valuable insights in one of our ongoing projects to investigate sulfur abundances through analyses of 100+ archived comet observations. In the first week of our visit to the EIF lab, we measured the electron-impact spectrum of CS₂ gas at various electron energies between 0 – 100 eV, with energies chosen based on known thresholds for CS, CS₂⁺, and atomic fragment production. During this time, we also began developing an emission model for CS in order to simplify the future analyses of these data. In the second week of the visit, higher-resolution spectra and several cross sections were measured in order to begin comparisons to existing literature. We also identified, for the first time, the emissions of atomic fragments (S I, S II) in the near-infrared red-ward of 600 nm.

22-EPN3-032: Soil carbonate clumped isotope-based reconstruction of temperature evolution over the Mid-Pleistocene Transition and the Late Pleistocene

Visit by Ramona Schneider, Uppsala University (Sweden), to TA2 Facility 17 – Isotoptech Stable/Clumped Isotopes Laboratory (Hungary).
Dates of visit: 20 February – 03 March 2023.

Report Summary: This study describes the use of carbonate clumped isotope thermometry as a method of reconstructing paleotemperatures from soil carbonate concretions. The method is based on the tendency of rare, heavy isotopes of carbon and oxygen to clump together in a single CO₂ molecule, which is temperature-dependent. 

The analysis was performed on 12 samples that forme under a Mediterranean climate regime in Tajikistan to investigate the suitability of these samples for clumped isotope thermometry. The reconstructed temperatures of the Tajik Holocene soil carbonate nodules from three different locations show promising results, indicating that the Δ₄₇ clumped isotope method provides reliable results for this sample type.

The obtained temperature values showed that these carbonates record temperatures that are biased towards summer temperatures. This is likely due to their formation during the summer when temperatures are highest and precipitation ceases after the maximum annual rainfall period. Even the results from older soil carbonates that formed under glacial and interglacial stages dating several glacial cycles back (MIS 11-12 and MIS 21) are well constrained, but a clear difference in formation temperature between glacial and interglacial stages could not be observed. This result can possibly be explained by formation processes of the soil carbonates, but more chronological and temperature data is required to further test this assumption and to investigate which exact period of the geological history is represented by the reconstructed temperatures. Despite these uncertainties, these initial results are very promising and highlight the potential of this method for paleotemperature reconstruction in Central Asia.

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.