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The evolution of the Ladon basin has been marked by intense geological activity and the discharge of huge volumes of water from the Martian highlands to the lowlands in the late Noachian and Hesperian. We explore the potential of the ExoMars Trace Gas Orbiter/Color and Stereo Surface Imaging System color image data set for geological interpretation and show that it is particularly effective for geologic mapping in combination with other data sets such as HiRISE, Context, and Compact Reconnaissance Imaging Spectrometer for Mars. The study area displays dark lobate flows of upper Hesperian to early Amazonian age, which were likely extruded from a regional extensional fault network. Spectral analysis suggests that these flows and the underlying rocks are ultramafic. Two distinct altered levels are observed below the lobate flows. The upper, yellow-orange level shows hundreds of structurally controlled narrow ridges reminiscent of ridges of listwanite, a suite of silicified, fracture-controlled silica-carbonate rocks derived from an ultramafic source and from serpentine. In addition to serpentinite, the detected mineral assemblages may include chlorite, carbonates, and talc. Kaolin minerals are detected in the lower, white level, which could have formed by groundwater alteration of plagioclase in the volcanic pile. Volcanism, tectonics, hydrothermal activity, and kaolinization are interpreted to be coeval, with hydrothermal activity and kaolinization controlled by the interactions between the aquifer and the hot, ultramafic lobate flows. Following our interpretations, East Ladon may host the first listwanite ridges described on Mars, involving a hydrothermal system rooted in a Hesperian aquifer and affecting ultramafic rocks from a magmatic source yet to be identified.

This paper presents the petrographic and textural characterization of some ornamental limestones widely used in UNESCO World Heritage sites in northeastern Italy, and the assessment of the main decay factors present in the environment where they are employed. Eleven carbonate building materials have been here considered, all commonly present in the built environment of northeastern Italy: two different varieties of Vicenza Stone (Nanto and Costozza), of Verona Stone (Red and Brown Verona), of Asiago Stone (Pink and White Asiago), and of Chiampo Stone (Ondagata and Paglierino), the Istria Stone (Orsera), the Aurisina Stone, and the Botticino Stone. The Carrara marble is also considered, and used as a reference material for the determination of the grain-size distribution. Stone durability was measured by accelerated ageing tests which reproduced freeze-thaw and salt crystallization cycles, among the main causes of deterioration in the region. Petrographic and textural features of these carbonate rocks as well as their porosity resulted to strongly influence their deterioration rate, and their knowledge is therefore essential when trying to predict stone decay as a function of the local environmental forcings.

The European Space Agency’s ANALOG-1 experiment is the culmination of 12 distinct METERON experiments carried out since 2011. These all address aspects of teleoperating a robotic asset from an orbital platform, i.e., technical implementation, user interfaces, autonomy and operations. The ANALOG-1 technology demonstration and operations concept experiment is based upon the surface mission scenario segment of the notional EL3 sample return mission. This segment focuses on the control of a lunar surface robotic asset from the Earth and from the Lunar Gateway. The experiment is taking place in two parts, with the first successfully completed from the ISS in November 2019. It assessed the effectiveness of a state-of-the-art robotic control interface to control a complex mobile robot from orbit, as well as evaluating the scientific interactions, during robotic-assisted geology exploration, between crew in orbit and scientists on the ground. Luca Parmitano operated the robot while he was on the ISS. For this experiment, a complex control station had been installed on the ISS. The experiment demonstrated the advantage of having an immersive control station and high level of robotic dexterity, with Luca finishing all his assigned and secondary geology targets ahead of time.

32 páginas.- 3 figuras.- 2 tablas.- 260 referencias, Nearly half a century ago, two papers postulated the likelihood of lunar lava tube caves using mathematical models. Today, armed with an array of orbiting and fly-by satellites and survey instrumentation, we have now acquired cave data across our solar system-including the identification of potential cave entrances on the Moon, Mars, and at least nine other planetary bodies. These discoveries gave rise to the study of planetary caves. To help advance this field, we leveraged the expertise of an interdisciplinary group to identify a strategy to explore caves beyond Earth. Focusing primarily on astrobiology, the cave environment, geology, robotics, instrumentation, and human exploration, our goal was to produce a framework to guide this subdiscipline through at least the next decade. To do this, we first assembled a list of 198 science and engineering questions. Then, through a series of social surveys, 114 scientists and engineers winnowed down the list to the top 53 highest priority questions. This exercise resulted in identifying emerging and crucial research areas that require robust development to ultimately support a robotic mission to a planetary cave-principally the Moon and/or Mars. With the necessary financial investment and institutional support, the research and technological development required to achieve these necessary advancements over the next decade are attainable. Subsequently, we will be positioned to robotically examine lunar caves and search for evidence of life within Martian caves; in turn, this will set the stage for human exploration and potential habitation of both the lunar and Martian subsurface., The following funding sources are recognized for supporting several of the contributing authors: Human Frontiers Science Program grant #RGY0066/2018 (for AAB), NASA Innovative Advanced Concepts Grant #80HQTR19C0034 (HJ, UYW, and WLW), and European Research Council, ERC Consolidator Grant #818602 (AGF), the Spanish Ministry of Science and Innovation (project PID2019-108672RJ-I00) and the "Ramon y Cajal" post-doctoral contract (grant #RYC2019-026885-I (AZM)), and Contract #80NM0018D0004 between the Jet Propulsion Laboratory, California Institute of Technology and the National Aeronautics and Space Administration (AA, MJM, KU, and LK).

We provide details about the procedure employed for the three-dimensional geological modelling of the lobes of comet Churyumov-Gerasimenko (67P). The two lobes of 67P are characterized by well visible terraces and elongated cliffs that revealed a pervasive layering arranged in an onion-like fashion. None of the layers can be traced for a continuity large enough to provide a means of stratigraphic correlation. Therefore, an explicit modelling approach of the layered structure is not easily applicable. We show how a very simple modelling strategy based on implicitly-defined analytical surfaces (spheres or ellipsoids), and requiring very limited operator decision-making, can be successfully applied to produce a geological model that easily fits the available scattered attitude observations. Our formulation has the advantage of providing a small set of parameters with a precise geometrical meaning that can be compared with other parameters of the lobes (i.e. center of ellipsoids and center of mass). The presented method originates outside commercial geological modelling software packages and required devising some ad-hoc solutions for the visualization of the resulting models in comparison with observations made on OSIRIS images. Some extracts of the visualization code, helpful for applying this procedure in similar operational contexts, are also presented.

The assessment of potential radon-hazardous environments is nowadays a critical issue in planning, monitoring, and developing appropriate mitigation strategies. Although some geological structures (e.g., fault systems) and other geological factors (e.g., radionuclide content, soil organic or rock weathering) can locally affect the radon occurrence, at the basis of a good implementation of radon-safe systems, optimized modelling at territorial scale is required. The use of spatial regression models, adequately combining different types of predictors, represents an invaluable tool to identify the relationships between radon and its controlling factors as well as to construct Geogenic Radon Potential (GRP) maps of an area. In this work, two GRP maps were developed based on field measurements of soil gas radon and thoron concentrations and gamma spectrometry of soil and rock samples of the Euganean Hills (northern Italy) district. A predictive model of radon concentration in soil gas was reconstructed taking into account the relationships among the soil gas radon and seven predictors: terrestrial gamma dose radiation (TGDR), thoron (220Rn), fault density (FD), soil permeability (PERM), digital terrain model (SLOPE), moisture index (TMI), heat load index (HLI). These predictors allowed to elaborate local spatial models by using the Empirical Bayesian Regression Kriging (EBRK) in order to find the best combination and define the GRP of the Euganean Hills area. A second GRP map based on the Neznal approach (GRPNEZ) has been modelled using the TGDR and 220Rn, as predictors of radon concentration, and FD as predictor of soil permeability. Then, the two GRP maps have been compared. Results highlight that the radon potential is mainly driven by the bedrock type but the presence of fault systems and topographic features play a key role in radon migration in the subsoil and its exhalation at the soil/atmosphere boundary.

Introduction. The ASI Space Science Data Center (SSDC) has a long-standing experience in space data management. Among its tools, MATISSE (Multi-purpose Advanced Tool for Instruments for the Solar System Exploration [1]) was created in 2013 to search, visualize and analyze data from planetary exploration missions. MATISSE, whose v2.0 update [2] is available at https://tools.ssdc.asi.it/Matisse/, allows users to analyze data from different missions, such as NASA Messenger and NASA Dawn, and the possibility of visualizing the data directly on the 3D shape of the targets greatly helped in reaching stunning scientific results. The work here presented points at improving and expanding the functionalities of the MATISSE tool for the Mercury explorations, by including the possibility to merge together the outputs of a thermophysical code of Mercury surface and the study of planet’s surface from a geological point of view. MATISSE for Mercury exploration. The ESA-JAXA BepiColombo mission is the first European mission to Mercury; the spacecraft will study in detail the surface, the exosphere and the magnetosphere of the planet. We have developed a thermophysical model with the aim to analyze the dependence of the temperature of the surface and of the layers close to it on the assumptions on the thermophysical properties of the soil. The code solves the one-dimensional heat equation, assumes purely conductive heat propagation and no internal heat sources; the surface is assumed to be composed of a regolith layer with high porosity and density increasing with depth. Calculations have been carried out to analyze the thermal response of the soil as a function of thermal conductivity. The model has been also used to study the sodium content in the planet's exosphere, whose origin is under investigation [3]; the MESSENGER mission has measured the exospheric sodium content as a function of time, detecting an increase at the "cold poles" (so called because of their lower than average temperature). In order to study the effect of surface temperatures on the sodium content in the exosphere, the temperature distribution calculated with the code has been used together with an atmospheric circulation model that calculates the exospheric sodium content [4]. Figure 1. Total sodium exospheric content as function of time and true anomaly angle, calculated in two cases: surface temperature from the thermophysical code (red line), and reference temperature (T proportional to ¼ power of cosine of illumination angle, blue line). A simplified version of the thermophysical code is available to the scientific community through MATISSE and, therefore, it could be crucial to interpret the data acquired by the instruments on board the BepiColombo mission, especially if it is taken into account that, through MATISSE, it is possible to analyze the surface of Mercury with data from NASA Messenger based on queries looking for specific geological units (as is already possible for Mars, Mercury and Ceres). Thanks to the data from the MDIS (Mercury Dual Imaging System [5]) camera on board the MESSENGER, it was possible to create a global map of the planet's surface. The identified lithologies can be analyzed and subsequently uploaded to our MATISSE tool in order to have the possibility to study the surface of Mercury directly from the site. On MATISSE it will be possible to select the data not only with the usual geographical coordinate, but on the basis of geological maps, so that the user can analyze observational and modeled data collected on areas with well-defined geology that allow to study the effects of the heterogeneity of surface. Figure 2. MATISSE homepage and selection of parameters to be observed. Example of selection of the Hokusay crater on Mercury's surface. The possibility of studying the Mercury surface directly from the tool will allow not only to make a detailed study of the terrain but understanding its formation will help science to understand how the solar wind affects some materials. For this reason our work will allow planetologists and astrophysicists to have all the available data for the study of the planet. In collaboration with the PlanMap and GMap teams, we are currently working to include the geological units identified on the surface of Mercury in order to be ready with the data that will come from the Bepi Colombo mission in order to have everything you need to study this planet in depth. Next steps. We plan to add in the tool all geological units mapped by GMAP team on Mercury surface. Moreover we will expand in the tool the possibility of searching for data based on the morphologies that the user wants to analyze (e.g. craters, valleys). Another goal will be to expand the use of the tool, making it similar to the geographic information system (GIS). We will expand the possibility of selecting specific areas to be analyzed, having clear the geographical position of the data. It will also be possible to obtain topographic profiles, select more data to be observed. All these analyses will be performed directly on the 3D models. The inclusion of these functionalities in the tool could produce a sensible step forward in the study of planetary geology, with the possibility of better exploiting different datasets and taking also into account the collaboration of different teams already leaders in this field. References. [1] Zinzi A. et al. (2016) Astron. Comput., 15, 16-28 [2] Zinzi A. et al. (2019) EPSC-DPS Joint Meeting 2019, id. EPSC-DPS2019-1272 [3] Rognini, E., et al. (2022), Effects of mercury surface temperature on the sodium abundance in its exosphere, Planetary and Space Science, 212 [4] Mura, A., et al. (2009), The sodium exosphere of Mercury: Comparison between observations during Mercury’s transit and model results, Icarus, 200, 1-11 [5] Hawkins et al., (2007). The Mercury Dual Imaging system on the MESSENGER spacecraft, Space Science Reviews, 131, 247–338

Póster presentado en Europlanet Science Congress 2022 Granada, Spain 18-23 September 2022

Introduction: Despite the large amount of information from orbital and in situ missions, the characteristics and evolution of Mars’ early climate are still widely debated among the scientific community. Morphological evidence dating back to about 3-4 billion years ago, such as valley networks [1], and the presence of several hydrated minerals [2] seem to indicate that Mars once had a “warm and wet” climate with abundant water on the surface and possibly even an ocean in the northern lowlands [1-3]. These conditions eventually changed through time leading up to the hyperarid and cold planet we observe today. The area of Meridiani Planum (MP), located SW of Arabia Terra, is well known for retaining multiple evidence of past aqueous activity [4] and a varied hydrated mineralogy [5]. The majority of the terrains exposed in MP formed at the Noachian-Hesperian boundary [6], that is between two important epochs of Mars: the Noachian (4.1-3.7 Ga), where most of the evidence for water is found, and the Hesperian (3.7-3.0 Ga), which is characterized by increasingly water-limited conditions. Constraining the potential water environment at the NH boundary is fundamental to understand Mars’ early climate and its evolution. In this study, we select 7 craters in Northern MP (figure 1) showing evidence of NH sediment infillings with hydrated materials (e.g., clays and sulfates) to assess in detail the stratigraphic sequence of the mineralogical units and understand their origin and diagenetic history. The craters are roughly aligned SE to NW following the general slope of the area from the highlands to the lowlands. If Mars experienced a “warm and wet” period, MP would represent a transition zone between the subaerial alteration environment of the highlands and the subaqueous environment of the Martian ocean. Therefore, the area would be easily affected by climatic changes whose evidence should be retained in its sedimentary sequences. We show here some preliminary results from 2 out of the 7 craters selected for the study: 1) a 15-km-wide crater named Mikumi, centered at Lat. 2.45°N, Lon. 359.96°E; 2) an 18-km-wide unnamed crater centered at Lat. 4.25°N, Lon. 2.85°E. Figure 1: THEMIS daytime image of Meridiani Planum. Selected craters are evidenced with points. Name (if given) and coordinates of the center for each crater are also indicated with a label. Most of the craters are unnamed. The arrows indicate the two craters described in this abstract. Datasets and methods: We investigate the mineralogy of the craters’ terrains through CRISM [7] hyperspectral data cubes mainly in the range 1.0-2.6 μm. This interval retains part of the key spectral features of primary rock-forming minerals, which constitute the Martian crust, and of most minerals produced by secondary processes such as aqueous circulation and alteration (e.g., clays and sulfates). MOLA, THEMIS, CTX and HiRISE data are then used for morpho-stratigraphy and camera imaging. Results: Two types of clays (smectites) with different Fe/Mg content, polyhydrated sulfates and monohydrated sulfates are observed in both craters (figure 2). Fe/Mg-clay spectra (e.g., nontronite and saponite) show absorptions at around 1.4, 1.9 and 2.3 μm with additional overtones at 2.4 μm. The exact position of the 2.3 μm feature depends on the relative Fe/Mg content in the clay mineral. We find some areas with clays richer in iron (e.g., nontronite), showing this feature centered at 2.305 μm, and clays richer in magnesium (e.g., saponite) where the absorption is centered at 2.310-2.315 μm. In Mikumi crater, polyhydrated sulfates (Mg sulfate) and monohydrated sulfates (kieserite) are detected stratigraphically below the clay-bearing layer. For the unnamed crater, the stratigraphic relationship of the units is still to be investigated. Figure 2: (top) CRISM spectra of detected mineralogy. Fe/Mg clays (smectites) are from Mikumi crater, mono and polyhydrated sulfates are from the Unnamed crater. The spectra are extracted from FRT0000BEF5 and FRT00009B5A TRR datasets respectively. (bottom) Laboratory spectra of clays and sulfates from the CRISM spectral library [8] (Mg Sulfate ID: CJB366; Kieserite ID: F1CC15; Saponite ID: LASA51; Nontronite ID: NCJB26). Discussion and conclusions: Clays and sulfates on Mars appear to have formed at different times and under different climatic conditions [9]. Clays are usually associated to Noachian terrains and may have formed under alkaline conditions in a “warm and wet” ancient Mars, whereas sulfates are typically associated to Hesperian surfaces and may have formed under a dryer and more acidic environment. Therefore, sulfates are expected to be found stratigraphically on top of clays, as they should have formed later in Mars’ history. However, this distinction between a clay-rich Noachian and a sulfate-rich Hesperian oversimplifies the history of the aqueous chemistry and climate of Mars especially near the NH boundary. Our analysis suggests a stratigraphic sequence with interleaving clays and sulfates at the NH boundary. Similar stratigraphic sequences have also been observed in other areas of MP (Southern MP) by [5]. In the case of [5], a clay-bearing layer is overlain by other sulfates, generating a sulfate/clay/sulfate stratigraphic sequence. All this argues is in favor of several distinct climatic episodes pacing the NH climatic transition. The results obtained so far will be enriched by further analysis of these areas along with a thorough investigation of the remaining 5 craters selected. Acknowledgments: Featured CRISM data were downloaded from the Planetary Data System (PDS). This project is partially supported by Europlanet RI20-24 GMAP project. References: [1] M. H. Carr and J. W. Head (2010) Earth and Planet. Sci. Lett., 293, 185-203. [2] B. L. Ehlmann and C. S. Edwards (2014) Annu. Rev. Earth Planet. Sci., 42, 291-315. [3] R. A. Craddock and A. D. Howard (2002) JGR, 107 (E11), 5111. [4] R. M. E. Williams et al. (2017) GRL, 44, 1669-1678. [5] J. Flahaut et al. (2015) Icarus, 248, 269-288. [6] B. M. Hynek et al. (2002) JGR, 107 (E10), 5088. [7] S. Murchie et al. (2007) JGR, 112 (E5), E05S03. [8] C. E. Viviano-Beck et al. (2015) MRO CRISM Type Spectra Library, NASA Planetary Data System. https://crismtypespectra.rsl.wustl.edu [9] J. P. Bibring et al. (2006) Science, 312, 400-404.

Introduction: In the Martian North Polar Cap, troughs are formed and enlarged by the erosive action of katabatic winds, blowing perpendicularly with respect to steep edges of the cap. Along these valleys deeper layering of the polar deposits are often exposed making it possible to study the stratigraphy of the upper part of the polar cap [1]. We focused our attention on a 140 km long and 500 m high scarp located in the North-Western edge, facing Olympia Planum, and where part of the North Polar Layered Deposits (NPLD) are exposed. NPLD deposits are finely layered and laterally continuous sequence of light and dark strata with sporadic unconformities in between, whose periodicity has been attributed to climatic and orbital variations [2]. In the polar cap, Tanaka et al. [3] has distinguished different polar units by means of surface image interpretation, hence our scarp exposes Planum Boreum 1 unit overlapped by Planum Boreum 3 unit, both composed of variable ice/dust content, but different thickness. Putzig et al. [4] identified instead seven units inside the polar cap on the basis of the pattern of radar reflections in the radargram-based stratigraphy thanks to the data provided by SHARAD. The stratigraphic sequence of our interest correlates with the upper part of the packet-inter-packet sequence of the unit G by Putzig et al. [4]. The aim of our work is to relate the composition and stratigraphy of the visible layered deposits with the subsurface radar reflectors, using the data acquired by the NASA Mars Reconnaissance Orbiter instruments. Data selection: We performed stratigraphic and geomorphologic interpretation on images of the Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE); band ratios and spectral signatures on a hyperspectral cube of the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM); subsurface reconstructions on radar reflectors obtained by the Shallow Radar (SHARAD). The integration of the results obtained by such a multi-score data-set underlies the possibility to join the SHARAD stratigraphy with the stratigraphic record recognisable at the surface including its compositional variability (Fig.1). Fig.1 – Data-set: MOLA DEM (a), CTX image (b), CRISM cube (c), HiRISE images (d, e) and SHARAD radargram tracks (f, g, h, i). Black rectangle in the North Polar Cap region shows the study area. Spectral analysis: Spectra for five Regions of Interest (ROIs) of about 50 pixels were acquired and are shown in Fig.2a-b. Fig.2 – (a) Regions of Interest over CRISM image detail; (b) Plot of five ROI average spectra: each colour line represents a ROI spectrum (continuum is removed). The exposed stratigraphy is composed of different amount of dry ice, water ice and basaltic dust [3]. Spectra A and B are well distinguishable, whereas the signatures of C, D and E appear similar, indicating comparable compositions. Spectrum A exhibits well developed water-ice absorption bands (1.5 and 1.95 µm), less development of same peaks might imply an increase of dry ice content. The 1 µm peak (water ice) is well visible in both A and B spectra, but less evident in C, D and E. Multiple absorptions at 1.65 and 2.06 µm, associated to CO2, are well visible in C, D and E. Other absorption bands (at 0.50, 1.02 and 2.30 µm for example) can be related to femic and aqueous alteration minerals. Spectrum A is similar to the signature of pure water ice, with less altered minerals, while C, D and E appear to be characterized by dry ice and femic minerals. Spectrum B appear to be transitional between these two end-members. Spectral indexes: Spectral indexes were produced using CRISM Analysis Toolkit (CAT) [5]. Indexes allowed us to create false colour images to highlight the presence/absence of specific minerals. Example of these are shown in Fig. 3 (see FED for the index definition). Fig.3 – Two false colour images created with spectral indexes (a) BDI1000VIS_BD15002_BD1435 representing ice compositions and (b) OLINDEX3_LCPINEX2_RBR to highlight mineral composition. Mapping and correlation to radar reflectors: Geological units were identified on CRISM and CTX data on the basis of morphology, composition, albedo and their stratigraphic relationship. Fig.4 displays the mapped units. Fig.4 – Geological map and relative units. WI-units: water-ice-rich deposits (blue), WF-unit: water ice and femic minerals deposits (light blue); DF-units: dry ice and femic minerals deposits (green); DI-units: dry-ice-rich deposits (yellow); Aeolian deposits (red); Gravitational deposits (purple). Fig.5 shows the geological units correlated with radargrams features. Variations of dielectric constant among strata are due firstly to presence of water ice in the surficial layers and dry ice in deeper ones, secondly to different amount of dust in radar units. These affect the signal reflectance: stronger if it is from water-ice layers. Additionally, high content of dust significantly decrease the radar signal, so units appear darker [4] [6]. The lines in Fig.5 represent lower contact of the geological units. Fig.5 – Correlation between geological units and radar reflectors. The colours of units are the same of geological map (vertical axis in time). Section track is shown in Fig.1. Discussion and conclusions: We provide a detailed compositional and geometrical characterization (using CRISM, HiRISE, CTX) of outcropping layered deposits of the North Polar Cap, to evaluate the potential for performing sound stratigraphic correlations with the subsurface reflectors identified in SHARAD radargrams. At a scale of single layers, compositional variations of basaltic dust content in the stratigraphic sequence were identified. This variability is visible especially in dry-ice-rich layers. Basaltic dust showed aqueous alteration, especially in water-ice-rich strata. Acknowledgments: We acknowledge support from the EU’s H2020 research and innovation program under grant agreement N° 871149 (GMAP). References: [1] Masse, M. et al. (2012) Earth and Planetary Science Letters, 317, doi: 10.1016/j.epsl.2011.11.035; [2] Byrne, S. (2009) Annual Review of Earth and Planetary Science, 37, doi: 10.1146/annurev.earth.031208.100101; [3] Tanaka, K. et al. (2008) Icarus, 196(2), doi: 10.1016/j.icarus.2008.01.021; [4] Putzig, N. et al. (2009), Icarus, 204(2), doi: 10.1016/j.icarus.2009.07.034; [5] Viviano-Beck, C. et al (2014), Journal of Geophysical Research, 119(6), doi: 10.1002/2014JE004627; [6] Lauro, S. et al. (2012), Icarus, 219(1), doi: 10.1016/j.icarus.2012.03.011.

Lava tubes, or pyroducts [1], are a peculiar type of lava caves originating from basaltic lava flows. These conduits are very efficient thermal structures that allow the lava to cover long distances before cooling down. Lava tubes, are typical features of lava fields found in volcanic-shield islands (e.g. Hawai’i, Canaries, Iceland, etc.) and intracontinental plateaus characterised by gentle slopes ( These structures are easily recognizable from the surface through the presence of skylights and roof collapses aligned in pit-chains, tracing the path of the underground conduit (Fig. 1). Analogous aligned collapses were seen on the surfaces of Mars and the Moon [2]. Thus, the great interest in studying large terrestrial lava tube systems is largely driven by their analogy with their extra-terrestrial equivalents. Figure 1: Comparison of lava tubes from different rocky bodies of the Solar System. From the left: Earth (Undara system, Australia), Mars (Arsia Mons region) and the Moon (Gruithuisen crater). The main difference between structures of different planetary bodies are due to intrinsic physical characters of the parental body and above all gravity. Indeed, a weaker gravity (as in the case of Mars and the Moon) results in higher effusion rates and, thus, larger lava flows and tubes (Fig. 1). This has led to pyroducts which are two or three orders of magnitude smaller in diameter on Earth (10 - 30 m) than on Mars (250 - 400 m) and the Moon (500 - 1100 m) [5]. Despite this different scaling, the largest lava tubes on Earth are considered to be very useful analogues to their extra-terrestrial counterparts. A clear understanding of how large pyroducts form and evolve remains elusive, even on Earth. Within this context, our work aims to identify the processes that shaped the formation of terrestrial lava tubes. Among the most studied pyroducts, the La Corona system (Lanzarote, Canary Islands, Spain) stends out for its geological context within the Canary Island Seamount Province (CISP) on which long-term and spatially focused volcanic activity developed over a poorly mobile tectonic plate. During the last 30 Ma, the absolute motion of the African plate has been nearly stationary (less than 20 mm/yr) [3]. This environment identifies the Canaries as one of the best terrestrial analogues of the Martian one-shell plate volcanism [4], and the impressive dimensions of La Corona lava tube (~9.7 km of total cave development, and a width reaching up to ~28 m for some of its sections) make it one of the most suitable lava tube for interplanetary analogies [6]. In order to understand the origin, evolution and degradation of the La Corona pyroduct, we have carried out a study of the satellite images of the northern region of Lanzarote, followed by field exploration of inner portions of the La Corona lava tube and adjacent areas. Combining terrestrial laser scanner (TLS) technology with field observations and geochemical analyses of the pre-existing lava enabled us to reconstruct the three-dimensional geometry of the lava tube system, the subsurface horizon through which it starts developing, and the volcanic series into which the pyroduct carved its path. What makes this inflated lava tube so interesting is the presence, between the flows the tube has crossed, of a red pyroclastic layer, resulting from the initial Strombolian activity of La Corona vent [7]. This weak layer of pyroclastic material played a major role in the development of the lava tube (Fig. 2), facilitating the emplacement of the inflation process and the excavation that followed [6]. By analogy, similar geological settings could be favourable for the formation of lava tubes on rocky bodies like Mars and the Moon since the volcanic sequences on such bodies can be frequently interleaved by either weak pyroclastic and regolith layers. Other influent parameters controlling erosion include slope variations of the paleo-surface (i.e., knickpoints), and the lava physical properties, both to be well investigated on terrestrial analogues to understand their role even on planetary contexts. Figure 2: Thermo-mechanical erosional stages of the lava tube in cross-sections. a) The primary effusive phase has covered the pyroclastic deposit of the initial Strombolian event; b) the inception of the tube by inflation starts exploiting the pyroclastic layer; c-d-e) progressive erosion and enlargement of the tunnel; f) post-cooling phase. On the walls are visible different layers of linings and flow ledges. The floor is covered by blocks and debris, remnants of the breaking down of the ceiling and lining walls. References [1] Coan, T. (1844). Missionary Herald. [2] Haruyama, J. et al. (2012) Trans. JAPAN Soc. Aeronaut. Sp. Sci. Aerosp. Technol. JAPAN 10. [3] Gaina, C. et al. (2013). Tectonophysics, 604, 4-25. [4] Meyzen, C. M., et al. (2015) Geol. Soc. London, Spec. Publ. 401. [5] Sauro et al. (2020) Earth-Science Rev. [6] Tomasi, I. et al. (pending) JGR – Solid Earth. [6] Carracedo, J. C. et al. (2003) Estud. Geol. 59.

Galileo Regio is a dark terrain of Ganymede extending approximately from 180°-120° W to 0°-60° N that shows high crater density and morphotectonic structures called furrows. Such structures are kilometric-scale brittle troughs bounded by high albedo rims and a low albedo floor, and arranged with circumferential and radial setting at the regional scale [1]. Furrows are generally interpreted as the remnants of a multi-ring impact basin similar to the Valhalla basin on Callisto [2]. Galileo Regio shows two main settings of the furrows, which allow their classification into two systems: the concentric furrows of Lakhmu Fossae system, which is crosscut by the radial furrows of the Zu Fossae system [3]. In addition, Galileo Regio shows local-scale structures that rework the pristine morphology of the Lakhmu Fossae furrows. In this contribution, we investigate the furrows of Galileo Regio at both regional- and local-scale to unravel the tectonic evolution of the dark terrain. We perform a structural mapping and geostatistical analyses of the furrows in Galileo Regio, identifying their hierarchy and tectonic setting originated by regional-scale kinematics. Structure attributes such as structure length, sinuosity, azimuth, spacing within the adjacent structures, have been quantitatively characterized and allow to perform the azimuthal distribution, the Length/Spacing [5] and the paleo-stress analyses [6]. Such analyses allow to identify the structural systems and to infer the past stress fields that affected Galileo Regio (maximum and minimum horizontal stress, i.e., SHmax and Shmin, respectively). A total of four structural systems have been recognized within Galileo Regio: i) the already known Lakhmu and Zu Fossae; and ii) the Lineated system and Precursor system, proposed by this work for the first time (Fig. 1). Such systems are the result of phases of the tectonic activity that affected Galileo Regio during the geologic history of Ganymede. We identify the sequence of such phases that allow to produce an evolutionary tectonic model (Fig. 2): i) t0 represents a NW-SE extension that formed the Lineated system; ii) t1 represents the impact that originated a multi-ring basin [3, 7], i.e., the Lakhmu Fossae; iii) t2 shows the extensional activity responsible for the formation of the light terrain of Uruk Sulcus [8] and for the formation of the extensional structures of the Precursor system; iv) t3 represents the kinematics consistent with the right-lateral transpression that has affected Uruk Sulcus [4] and formed the Zu Fossae; and v) t4 presents a right-lateral strike-slip that contributes to the formation of the Precursor system. The obtained results and the presented model will be used for the scientific preparation of dedicated high-resolution observations that will be taken with the JANUS instrument [9] onboard the JUICE mission [10]. Acknowledgments: The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References: [1] Patterson, W. et al. (2010). Icarus 207,845–867; [2] McKinnon, W.B. and Melosh, H.J. (1980). Icarus 44 (2), 454–471; [3] Prockter, L.M., et al. (2000). Journal of Geophysical Research: Planets, 105(E9), 22519-22540; [4] Kersten, E., et al. (2021). Planetary and Space Science, 206, 105310; [5] Rossi, C., et al. (2018). Tectonophysics 749, 72–87; [5] Delvaux, D., and Sperner, B. (2003). Geol. Soc., London, Special Publications, 212(1), 75-100; [7] Hirata, N., et al. (2020). Icarus, 352, 113941; [8] Pappalardo, R.T., et al. (1998). Icarus, 135(1), 276-302; [9] Palumbo, P., et al. (2014). 45th LPSC Meeting. Abstract #2094; [10] Grasset, O., et al. (2013). Planetary and Space Science, 78, 1–21.

Data from NASA MESSENGER spacecraft highlighted that Mercury’s surface and composition are more varied than previously thought. Despite being the closest planet to the Sun, indeed, Mercury is rich in volatiles and its surface shows evidence of volatile-driven processes such as the formation of hollows and explosive volcanism. Even MESSENGER’s color-derived basemaps, moreover, highlight relevant color variations of the hermean surface possibly indicating age and compositional differences between adjacent materials. The ongoing mapping for the eastern H9 Eminescu quadrangle (22.5°N-22.5°S, 108°E-144°E) [1] led to a thorough knowledge of the area that allowed the definition of scientific targets of interest to be investigated by the SIMBIO-SYS cameras [2] onboard the ESA-JAXA BepiColombo mission [3] coupled with other instruments such as MERTIS, BELA, MGNS and MIXS. Proposed targets range from hollows to volcanic features, from craters and deformational structures and specific terrains and aim at shedding light on scientific questions concerning Mercury’s origin and evolution [4]. In particular, proposed targets aim to i) determine the abundance and distribution of key elements, minerals and rocks on the hermean crust, ii) characterize and correlate geomorphological features with compositional variations, iii) investigate the nature, evolution, composition and mechanisms of effusive and explosive events, iv) determine the formation and growth rates of hollows, the nature of processes related with volatile loss and their mineralogical and elemental composition of volatiles, v) determine the displacement and kinematics of tectonic deformations and the mechanisms responsible for their formation and vi) verify the occurrence of any detectable change in and around hollows and pyroclastic deposits since MESSENGER observations. Acknowledgements: We acknowledge support from the Italian Space Agency (ASI) under ASI-INAF agreement 2017-47-H.0. References: [1] El Yazidi et al., 2021, EPSC. [2] Cremonese et al., 2020, Sp. Sci. Rev. [3] Benkhoff et al., 2010, Plan. Sp. Sci. [4] Rothery et al., 2020, Sp. Sci. Rev.

Introduction: The physical properties of a particulate surface, like roughness, grain size, shape and transparency affect how it reflects the incoming light. This concept is used in planetary photometry to infer the surface properties of a celestial object from multiple observations taken from different directions and solar illumination (Hapke et al. 2012). Models linking the observed surface brightness with parameters related to physical properties of the surface have been established. The estimation of such parameters is referred as photometric modelling (Domingue et al., 2016). On Mercury, this technique has been employed to construct monochrome and color global mosaics, but it was never applied to investigate local surface features (Domingue et al., 2016). Therefore, the photometric modelling of Mercury’s surface features represents a novel and useful tool to investigate their nature. In addition, the identification of high-performance photometric models of any given surface material over multiple wavelengths enables to accurately predict the amount of reflected sunlight that will be observed through remote cameras and spectrometers. In this abstract, we first describe our modelling approach, discuss its improvement with respect to current available photometric models of Mercury, and present a few science cases in which it has been applied. Then, we will also show how this methodology is being applied for the calibration of SIMBIO-SYS observations that will be acquired during the Mercury Orbit Insertion (MOI) phase of the mission. Methodology: we first analyze the Tyagaraja and Canova craters hollows (i.e., tens meters to several km-sized shallow, irregular, flat‐floored depressions characterized by bright interiors and haloes, Blewett et al., 2011), which are covered by multiple overlapping 8 filter MDIS/WAC (Hawkins et al., 2007) images with resolution higher than 665 m/px and phase angles from 30° to > 100°. Over this region, we construct a latitude-longitude sampling grid with 665 m spacing. For each point we retrieve the surface reflectance and the solar illumination and observation angles using the 3D information of the global USGS DTM and the spacecraft and Sun position information within the observation SPICE kernels. This dataset is fitted with the Hapke and Kaasalainen-Shkuratov photometric models and estimates of their parameter are obtained for each point of the grid (see for example Fig 1C). Results Modelling performance: Our results suggest that photometric models derived from the inversion of multiple, overlapping observations are more accurate, especially for bright targets, rather than global photometric models of Mercury (Fig 1A,B). Overall, we estimate a modelling accuracy of better than 10% at 3σ, comparable with the radiometric noise level of the observations. Hollows results: Our results suggest that hollows are more backscattering than the floor of the crater in which they form. This is consistent with hollows being made of a material rich in holes and/or vescicles, in agreement with a formation by devolatilization. In addition, we find that they are smoother than the crater floor, consistently with the emplacement of a fine particles halo during hollow growth. Figure 1. Modeled vs Observed reflectance obtained with our KS3 model (gold) and the global one for Mercury for Canova (A) and Tyagaraja (B) craters. C) Example of Hapke single scattering albedo map of Tyagaraja crater. D) MOI SIMBIO-SYS footprints and the Regions of Interests (ROI) that are being analyzed for the cross-calibration of the three channels. Cross calibration of the SIMBIO-SYS channels: SIMBIO-SYS is a suite of three instruments, a high-resolution imager (HRIC), a stereocamera (STC) and a spectrometer (VIHI). Because of the dual-spacecraft configuration of BepiColombo, standard star observations with SIMBIO-SYS are not feasible until the satellite will be in its nominal orbit around Mercury. It is therefore pivotal to identify regions on the surface of Mercury with well-defined spectrophotometric properties that can be used as ground truth for the initial cross calibration of the three channels, prior to standard stars observations. Such regions will be also used to verify the integration times before the planning of the Global Mapping phase and to characterize the instrument straylight and pixel response non uniformity. The ROI will be observed during the Mercury Orbit Insertion (MOI) orbits where no standard stars pointing are still allowed. Therefore, we applied our methodology to identify ROIs within these orbits that currently have at least 5 MDIS/WAC observations, phase angles > 110° and resolutions higher than 665 m/px (Fig 1D). The retrieved photometric models for these regions will be used to determine accurate spectra (at the MDIS/WAC wavelengths) that will be interpolated within the SIMBIO-SYS photometric system and used to cross-calibrate the three channels of the instrument. Discussion Our analysis shows that overlapping multiangular MDIS/WAC observations can be used to invert local photometric models of the surface. This approach allowed us to initially study and characterize the scattering properties of hollows, finding that they are smoother and more back-scattering than the crater floors. This is consistent with hollows being formed by a volatile-release mechanism and emplacement of a halo of fine particles. We also found that this modelling approach is more accurate, in particular for high reflectance, than current global photometric models of Mercury. This led us to apply our methodology to selected locations that will be observed by SIMBIO-SYS during the MOI phase, and that will be used for absolute calibration of its three channels. More details will be presented at the conference. Acknowledgments and Data We gratefully acknowledge funding from the Italian Space Agency (ASI) under ASI-INAF agreement 2017- 47-H.0.

Production of photogrammetric 3D models of the ancient coral reefsof Lumignano and their potential utilisation for geoconservation, scientific and educational purposes.&nbsp

Lunar Gravitational-wave Antenna (LGWA) proposes to deploy an array of high-end seismometers on the surface of the Moon. The LGWA network will measure the lunar surface displacement excited by Gravitational waves (GWs) with a targeted observation band of 1mHz – few Hz. Seismic noise in that frequency band is very low due to the absence of atmosphere and oceans, representing the main inherent advantage that makes the Moon an ideal target for a GW detection experiment. The scientific and technical challenges of LGWA are diverse. Since its initiation, LGWA has relied on experts from fundamental physics, astrophysics, geophysics, engineering, and planetary science. The collaboration is currently organized in working groups (WGs) to cover five key themes: GW science, lunar science, payload, deployment, and operations. At the beginning of 2022, we started the activities of WG2 to assess the current knowledge of the lunar environment. We aim to characterize and develop models of deployment scenarios suitable for LGWA sensors, via a multi-pronged approach of data analysis and on-field experiments probing terrestrial analogs of lunar terrains. Besides characterizing the lunar seismic background noise, other goals of the group are related to modeling the lunar interior structure as well as Moon’s normal modes. These will be further used to develop a model of the interaction between the Moon and GWs. The knowledge about the displacement level of this excitation and the background noise will be used to define novel techniques for background noise reduction.For this purpose, WG2 is composed of physicists, engineers, geophysicists, and geologists. For our activities, we chose an interdisciplinary approach that requires initial communication efforts to create a common ground that will evolve into a crucial baseline activity for the whole LGWA project.Here we will report our progress in the first months of the activity of our collaboration.

Geological map of Lumignano area (Vicenza, Italy) and description of its geology., {"references":["Gray M., 2008 – Geodiversity: developing the paradigm. Proceedings of the Geologists' Association, vo. 109, pp. 287-298","Coratza, P., Bollati, I.M., Panizza, V., Brandolini, P., Castaldini, D., Cucchi, F., Deiana, G., Del Monte, M., Faccini, F., Finocchiaro, F., Gioia, D., Melis, R., Minopoli, C., Nesci, O., Paliaga, G., Pennetta, M., Perotti, L., Pica, A., Tognetto, F., Trocciola, A., Valentini, L., Giardino, M., Pelfini, M., 2021. Advances in Geoheritage Mapping: Application to Iconic Geomorphological Examples from the Italian Landscape. Sustainability 13, 11538. https://doi.org/10.3390/su132011538","Martin, S., Reynard, E., Pellitero Ondicol, R., Ghiraldi, L., 2014. Multi-scale Web Mapping for Geoheritage Visualisation and Promotion. Geoheritage 6, 141–148. https://doi.org/10.1007/s12371-014-0102-3","Frost, S.H., 1981. Oligocene Reef Coral Biofacies of the Vicentin, Northeast Italy. SEPM Special Publications 30, 483-539. https://doi.org/10.2110/pec.81.30.0483","Nebelsick, J.H., Bassi, D., Lempp, J., 2013. Tracking paleoenvironmental changes in coralline algal-dominated carbonates of the Lower Oligocene Calcareniti di Castelgomberto formation (Monti Berici, Italy). Facies 59, 133–148. https://doi.org/10.1007/s10347- 012-0349-6"]}

The surface of Ganymede, which is the biggest satellite of Jupiter, shows strong tectonic deformation affecting both its geologic units, i.e., the younger light terrain and the older dark terrain. The dark terrain is characterized by low albedo, high crater density and furrows, which are morphotectonic structures formed by brittle deformation. Furrows are straight to curved fragments of troughs, with high albedo rims that bound a low albedo floor. Two systems have been recognized at the regional scale, which are the Lakhmu Fossae, whose furrow setting follows a concentric pattern resulting from a multi-ring impact basin, and the Zu Fossae, which follows a radial setting. In addition, local scale structures have been identified superimposed on the regional scale systems, leading to the reworking of the pristine structures. In this contribution, we investigate the tectonic evolution of the furrows in Galileo Regio (approximately from 180°-120° W to 0°-60° N), at both regional and local scale, with the identification of the tectonic events responsible for the deformation of this dark terrain. We performed a structural mapping and geostatistical analyses of the attributes of the mapped structures, such as the length, sinuosity, azimuth, spacing within the adjacent structures. Their quantification allows us to recognize a total of four structural systems within the area and to unravel the paleo-stress fields that have originated them. We prepared an evolutionary tectonic model of the furrow systems of Galileo Regio that shows the dynamics and the induced kinematics. We suggest that Galileo Regio underwent a sequence of tectonic phases associated with extensional and strike-slip regimes, these latter consistent with the kinematics that affected the light terrain of the adjacent Uruk Sulcus. This work advances the assumption that the dark terrain has been later affected by the same tectonics that deformed the light terrain and confirms the rejuvenation of the dark terrain towards a possible future transformation into light ones. The obtained results will be used for the scientific preparation of dedicated high-resolution observations that will be taken with the JANUS instrument onboard JUICE mission.Acknowledgments: The activity has been realized under the ASI-INAF contract 2018-25-HH.0.

The surface of Ganymede, the largest satellite of Jupiter, consists of a strongly deformed and tectonized brittle icy crust which stands on top of a large liquid body, possibly a global subsurface ocean. In fact, by means of multiple Galileo orbital mission flybys both geophysical and structural geology measurements constrained the average icy shell thickness to be comprised between 100 and 150 km. The surface can also be divided into two main units: bright and dark terrains depending on their relative albedo, impact crated density and tectonization. Furrows and grooves represent most of the structures on Ganymede’s surface, which are essentially extensional faults, dilatant structures and strike slip faults. We hereby present a 3D geologic modelling of the region of Uruk Sulcus based on structural mapping (Rossi et al., 2020) and using techniques borrowed from oil and gas exploration.The Uruk Sulcus area is a NW-SE bright terrain of ~400 km by ~2500 km size located between 150W-180W and 30N-10S, and characterized by pervasive sets of parallel/sub-parallel grooves of 10s-to-100s km length. The most favored hypotheses relate its formation either to a purely extensional context forming a tilt-block normal faulting, or to crustal necking with creation of horsts and grabens, or to be the result of a major dextral transpression. The overall structural framework and the fault geometries (in the form of 3D meshes) was created according to existing literature and with geologic interpretation and anchored on the surface to the global DEM by Zubarev et al., (2017), and at depth to the brittle ice-subsurface ocean interface to an average value of 120 km. This ice thickness value was obtained, among other methods, also by analyzing the scaling laws ruling the spatial distribution and the length size distribution of grooves and extensional structures, which proved to be fractal. One of the implications of this fractal behavior is that the structures themselves can be interconnected forming a percolating network favoring fluid circulation and connecting the subsurface ocean with the surface (see Lucchetti et al., 2020 and references therein).By means of 3D modelling, we were able to isolate volumes of ice encompassed by major strike-slip structures of Uruk Sulcus and to exploit the scaling laws ruling the structures within such areas, in order to numerically simulate a DFN (digital fracture network) crosscutting the entire volume of ice.This way we could analyze the volume of ice crosscut by such fracture network, and to predict the locations at surface where percolation is favored. Acknowledgments: The activity has been realized under the ASI-INAF contract 2018-25-HH.0.

Alpine peatlands occur in alpine, sub-alpine and mountain regions of the world and can be frequently found on the Alps as well as on the Andes, on the Tibetan Plateau, on the Australian Alps and in other regions of the world. Italian Alps host a large number of relatively small bogs and fens that can be found on gently sloping surfaces or in small valleys created by past glaciers. The high precipitation-low temperature climatic regime ensures large water availability to these ecosystems. The uniqueness and importance of peatlands in the Alpine territory is strongly linked to the countless ecosystem services that they provide, including their ability of sequestering and stocking carbon, providing habitat for flora and fauna including endangered species, supporting important biological diversity, being reservoir of high-quality freshwater during warm and dry seasons, and having the role of paleo-climate archives.Despite their importance, the peatlands of the Alps are still poorly studied and incompletely mapped, probably because they are relatively small and difficult to access. The use of remote sensing techniques provides a possible solution, allowing extending local measurements to wider areas in a fast and cost-effective way. Our hypothesis is that the spatial distribution of different plant associations as well as the spatial variability of vegetation biomass may provide important information for mapping the spatial distribution of peat properties, thus making remote sensing an effective method for peatland studies.In this work, we present the results obtained by using data collected by Unmanned Aerial Vehicles (UAVs) on the Val di Ciampo alpine peatland (Province of Belluno, northeast Italy) in July 2021. LiDAR data, hyperspectral data and aerial digital photos were simultaneously collected on an area of 88.000 m2. Field observations and measurements were performed in the same period, providing georeferenced ground information on vegetation and peat characteristics. Peat and vegetation samples were collected and analyzed in the lab. For each vegetation association we measured the height of plants and determined their above- and below-ground biomass based on 20 above-ground and 15 below-ground samples. As for the peat, we measured the peat thickness and determined the bulk density and the organic carbon content of 46 samples.Our results show that some of the correlations found between the parameters that characterize different vegetation associations can be used to calibrate the data collected by UAVs and extend the results from point locations to the entire peatland. For example, we found that the aboveground biomass is significantly correlated (r = 0.81, p < 0.001) to the local average vegetation height, therefore both LiDAR data and the Digital Surface Model (DSM) extracted from the photos can be used to estimate and map the vegetation aboveground biomass. The correlation between the surface microtopography and the aboveground biomass will also be presented, as well as other correlations between vegetation patterns and peat depth and properties. The significance of combining UAVs multi-sensor data with field observations for the characterization of Alpine peatlands will be discussed.

Radon (222Rn) is a radioactive gas widely considered an indoor air pollutant due to its harmful effects on human health (WHO, 2009). The Geogenic Radon Potential (GRP) quantifies what “Earth delivers” in terms of radon and represents the most important contributor to Indoor Radon Concentrations (IRC) indicating the potential risk over an area (Bossew 2015). This is the special case of some municipalities in Pustertal/Pusteria Valley (Bozen/Bolzano, North-Eastern Italy) which display a high IRC, based on Indoor measurements carried out by Minach et al. (1999), exceeding the threshold value recommended by EURATOM 59/2013. These municipalities are located along a wide brittle-fracture zone between the Pusteria Line (PL, the eastern part of Periadriatic Lineament) and the Deffereggen-Anterselva-Valles (DAV) faults. This fractured zone may act as preferential pathway for radon transport and migration by carrier gases (mainly CO2 and CH4), strongly contributing to its geogenic component. A GRP map of the study area has been developed based on field measurements of radon, thoron (220Rn) and other soil gases (CO2, CH4, H2, O2, H2S) according to a sampling grid in an area of 6x10 km, and along three profiles crossing above mentioned fault lines in Terenten/Terento, Mühlen/Molini and Pfalzen/Falzes specific areas. The GRP map was constructed by using soil gas radon data and other proxy variables in a spatial regression model. Soil gas measurements have been supported by high-resolution gamma-ray spectrometry on 16 rock samples belonging to the main outcropping lithologies in the study area i.e. granite, orthogneiss, micaschist-paragneiss, phyllite. The preliminary radon map highlights a wide area of radon anomaly located to the North of the Periadriatic Lineament. The global trend of these radon anomalies follows the structural trend of the brittle fracture zone between PL and DAV faults and tends to close from the eastern part (Pfalzen/Falzes) toward the western part (Terenten/Terento) of the study area. In particular the easternmost sector of the map displays a wide north-south area of radon anomaly related to a wide brittle-fracture zone probably composed by a system of sub-parallel faults. The spatial distribution of radon anomalies confirms the key role played by the Pustertal/Pusteria fault system in the fluid degassing processes enhancing geogenic radon potential of the Pustertal/Pusteria Valley. Keywords: Natural Radioactivity, Geogenic Radon Potential, Indoor Radon, Periadriatic Lineament References:Bossew Peter. Mapping the Geogenic Radon Potential and Estimation of Radon Prone Areas in Germany. Radiation Emergency Medicine 2015 Vol. 4, No.2 13-20.Council Directive 2013/59/EURATOM. Basic safety standards for protection against the dangers arising from exposure to ionising radiation.Minach L., Verdi L., Marchesoni C., Amadori C. Radon in Südtirol. Environmental Protection Agency. 1999.WHO 2009. Zeeb H. and Shannoun F. (eds.) WHO handbook in Indoor Radon - a public health perspective. ISBN 978 92 4 1547672.

Morpho-stratigraphic maps lay the groundwork for the geologic characterization of a planetary surface. Nevertheless, they do not provide the same level of information as geologic Earth maps. They thus need to be integrated with information derived from the multispectral and hyperspectral data. The Clementine-based map produced for the lunar far side Tsiolkovskiy crater (20.4°S, 129.1°E) [1] allowed a first understanding of the composition, in particular for the basaltic infilling, of this crater. In this work, the higher spectral and spatial resolution data obtained by the M3 imaging spectrometer [2] were used to derive a set of spectral indices (reflectance at 540 nm, band depth at 1000 and 2000 nm, and the spectral slope between 540 nm and the maximum of the first and second shoulder of the band depth at 1000 nm) helpful in enhancing compositional variations of the area. Rather than interpreting each index separately, 10 Spectral Units (Figure 1) conveying the spectral information fulfilled by all the spectral parameters were defined [3]. Notably, three Spectral Units discriminated on the smooth infilling of Tsiolkovskiy, which are fairly well correlated with the ones described on the basis of the Clementine UVVIS color ratio basemap, present the lowest reflectance values and the strongest absorptions around 1000 and 2100-2200 nm. Figure 1. Spectral Units map of Tsiolkovskiy crater. Each unit summarizes the information held in several spectral parameters. Given that pyroxenes are among the most common minerals on the Moon, we then compared the absorption band centers at 1000 and 2000 nm of the Spectral Units with those of RELAB synthetic pyroxenes [4,5]. The analysis revealed that most of the material of Tsiolkovskiy is characterized by a mineralogy similar to pigeonite or augite, a low Ca and Mg content and relatively high Fe. Some Spectral Units, however, do not fall inside a defined range and show a displacement of the band center at 1000 nm, possibly indicating the influence of a different component to be further investigated. This work represents a step forward in the understanding of the mineralogical and compositional analysis of the Tsiolkovskiy crater and in the integration between morpho-stratigraphic and spectral units and between spectral units defined on different multispectral data. Acknowledgements: We gratefully acknowledge funding and support from the PRIN-INAF2019-MELODY project and support from the EU’s H2020 research and innovation program under grant agreement No. 871149 (GMAP). References: [1] Tognon et al., 2021, MDPI. [2] Pieters et al., 2009, Current Science. [3] Zambon et al., 2022, JGR. [4] Klima et al., 2011, Meteoritics and Planetary Science [5] Klima et al., 2011, JGR.

The global tectonics of Mercury is dominated by contractional features mainly represented by lobate scarps, high relief ridges, and wrinkle ridges. These structures are the expression of thrust faults and are linear or arcuate features widely distributed on Mercury. Locally, these structures are arranged in long systems characterized by a preferential orientation and non-random spatial distribution. In this work we identified five thrust systems, generally longer than 1000 ​km. They were named after the main structure or crater encompassed by the system as: Thakur, Victoria, Villa Lobos, Al-Hamadhani, and Enterprise. In order to gain clues about their formation, we dated them using the buffered crater counting technique, which can be applied to derive the ages of linear landforms such as faults, ridges and channels. To estimate the absolute age for the end of the thrust system’s activity, we applied both Le Feuvre and Wieczorek Production Function and Neukum Production Functions. Moreover, to further confirm the results obtained with the buffered crater counting method, the classic stratigraphic approach has been adopted, in which a faulted and an unfaulted craters were dated for each system. The results gave consistent ages and suggested that the most movements along major structures all over Mercury most likely ended at about 3.6–3.8 ​Ga. This gives new clues to better understand the tectonics of the planet and, therefore, its thermal evolution. Indeed, the early occurrence of tectonic activity in the planet’s history, well before than predicted by the thermophysical models, coupled with the orientation and spatial distribution of the thrust systems, suggests that other processes beside global contraction, like mantle downwelling or tidal despinning, could have contributed to the first stage of the planet’s history. Keywords: Mercury, Thrust systems, Crater counting, Thermal evolution, Planetary geology, Structural geology

Showcase of the 3D explicit reconstruction possibilities on the Crommelin crater inner deposits on Mars

Ganymede’s dark terrain represents the older geologic unit of the satellite, subsequently crosscut by swaths belonging to the younger light terrain. Compared to the light terrain, the dark terrain shows low albedo, higher crater density and morphotectonic structures called furrows. These structures are radial or circumferential fragments of troughs bounded by high albedo rims and a low albedo floor, generally thought being the remnants of a multi-ring impact basin similar to the Valhalla or Asgard basins on Callisto [1, 2]. In particular, in Galileo Regio and Marius Regio, the furrow systems show a concentric pattern centered at around 20° S 180° W, which is the assumed location of the crater formed by an impactor of 50-150 km in radius [3, 4]. Many furrows have been preserved until the present day in their pristine form, while some of them have acted as zones of weakness re-used by subsequent tectonic deformation. For this reason, they show a more complex morphology and are likely considered as precursors of light grooved terrain formation. In this contribution, we perform a structural mapping at the regional scale of the furrows in Galileo Regio, identifying their hierarchy and tectonic setting originated by the regional scale kinematics. Our mapping reveals that transpression, already recognized in the adjacent Uruk Sulcus area [5], affects the dark terrain of Galileo Regio, too. We mapped the structures in Galileo Regio (Fig. 1) by considering their spatial distribution and crosscutting relationships. In addition, we mapped the local-scale fractures that have tectonically modified remnants of furrows by leaving a deformation zone with higher albedo with respect to the surrounding dark material. These fractures show geometries and features associated with the Riedel shear, and synthetic and antithetic structures that form in strike-slip regimes [6]. The NE-SW and NW-SE trending structures that crosscut the concentric furrow systems occur from Uruk Sulcus to approximately 60° N and have been recognized as conjugate (Fig. 2). Hence, the setting of the mapped furrows and their associated structures allows identifying the (paleo)stress field that has affected this dark terrain. We infer that Galileo Regio has been characterized by regional kinematics consistent with the right-lateral transpression that has affected Uruk Sulcus. It is possible to recognize a ≈ NE-SW trending maximum horizontal stress (σh max) responsible for a shortening associated with strike-slip in the area that extends from 180°-120° W to 0°-60° N. Therefore, we can assume that the dark terrain has been deformed by the same tectonic processes that have formed the light grooved terrain of Uruk Sulcus. This work confirms the key role that transpression has played in the leading hemisphere of Ganymede and the reactivation (and possibly the inversion) of the furrows in Galileo Regio, which have followed a deformation history beginning from an impact origin to a tectonic remodeling. Further geo-statistical analysis will be performed to support this reconstruction. Obtained results from this study will be used for the scientific preparation of dedicated high-resolution observations that will be taken with the JANUS instrument [7] onboard JUICE mission [8]. Acknowledgements: The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References: [1] McKinnon, W.B., Melosh, H.J., 1980. Evolution of planetary lithospheres: evidence from multiringed structures on Ganymede and Callisto. Icarus 44 (2), 454–471. https://doi.org/10.1016/0019-1035(80)90037-8. [2] Prockter, L. M., Figueredo, P. H., Pappalardo, R. T., Head, J. W., & Collins, G. C. (2000). Geology and mapping of dark terrain on Ganymede and implications for grooved terrain formation. Journal of Geophysical Research: Planets, 105(E9), 22519-22540. [3] Prockter, L.M., Collins, G.C., Murchie, S.L., Schenk, P.M., Pappalardo, R.T., 2002. Ganymede furrow systems as strain markers: implications for evolution and resurfacing processes. In: 33rd Lunar and Planetary Science Conference, Abstract #1272. Lunar and Planetary Institute, Houston. [4] Hirata, N., Suetsugu, R., & Ohtsuki, K. (2020). A global system of furrows on Ganymede indicative of their creation in a single impact event. Icarus, 352, 113941. [5] Rossi, C., Cianfarra, P., Salvini, F., Mitri, G., Massé, M., 2018. Evidence of transpressional tectonics on the Uruk Sulcus region, Ganymede. Tectonophysics 749, 72–87. https://doi.org/10.1016/j.tecto.2018.10.026 [6] Fossen, H. (2010). Structural geology. Cambridge, UK: Cambridge University Press. [7] Palumbo, P. et al. 2014. JANUS: The Visible Camera Onboard the ESA JUICE Mission to the Jovian System. 45th LPSC Meeting. Abstract #2094. [8] Grasset, O., Dougherty, M. K., Coustenis, A., Bunce, E. J., Erd, C., Titov, D., et al. (2013). JUpiter ICy moons Explorer (JUICE): An ESA mission to orbit Ganymede and to characterise the Jupiter system. Planetary and Space Science, 78, 1–21.

The surface of Ganymede has first been observed by the Voyager missions in 1970’s highlighting the presence of a deeply tectonized environment. Galileo Mission in 1996 imaged the Jovian satellites also providing at high-resolution images at targeted places during its flybys. Ganymede's crust is mainly composed of a brittle ice overlying a subsurface ocean, whose depth was constrained to be ~100-150 km [1]. The surface of Ganymede can be subdivided into dark and bright terrains depending on their crater density, differences in albedo and surface morphology. The latter is driven mainly by tectonization, characterized by presence of furrows and grooves. These structures represent the brittle deformation of the icy shell. We focus on the bright terrain located in the region of Uruk sulcus, a NW-SE terrain ~400 km wide and ~2500 km long located between 150W -180W and 30N-10 S strongly deformed by sets of parallel/sub-parallel (often evenly-spaced) grooves both at a regional and local scale. The presence of such structures in light terrains is hypothesized to be determined by tilt-block normal faulting [2], by crustal necking similar to mid ocean ridges [3], or by major dextral transpression, as in the case of Uruk sulcus [4]. It has been demonstrated that such structures show a fractal spatial clustering, and represent a preferential pathway for fluid from the ~100-150 km-deep ocean [1]. We are testing different 3D geomodelling approaches hence deriving more information on both the volume of the fractured brittle ice crust and the most favored location of actual percolation. Nowadays 3D geomodelling is approaching the planetary geology framework, as testified by the outcomes of the PLANMAP Horizon 2020 project [5, 6, 7, 8, 9]. With information either derived from direct surface observations and measurements and/or also constrained by geologic interpretation, it is possible to derive a 3D geomodel of the subsurface that represents specific geologic properties or geometries. We built a preliminary Uruk sulcus model geometry using the global DEM [10] as an initial, low-resolution surface textured with the controlled global mosaic from DLR of Voyager 1, 2 and Galileo images at an average resolution of 359 m/pixel. This served as an upper surface boundary to project the structural mapping from Rossi et al., (2020) and also as an anchor point to reconstruct the major Uruk sulcus structures. As a lower model boundary, the icy crust is constrained at depth by the ocean-ice interface. We used the depth value calculated using the fractal clustering analysis in [1] related to Uruk sulcus. We were able to reconstruct a preliminary qualitative model of the fault geometries for GUS1 (Grooves of Uruk Sulcus 1) system deformation ([4] as a large-scale structural framework. As a first test we focused on a smaller region in the sigmoidal area named S2 and containing the GUS3 (see white square in figure 1b). We extracted a voxel-based volume of icy crust comprised between the surface, the lower ocean-ice interface bounded by the major fault lines delimiting GUS3. At this location a major set of high-angle extensional structures at NE-SW arranged in a right-stepping en-echelon geometry are present, together with other two lower in number grooves families with NW-SE and NS orientations. With this voxel-based volume and knowing the scaling laws of the size distributions of these feature and their azimuths, it is possible to simulate a DFN (Digital Fracture Network) for each of the fractures’ families (fig. 2a). With the DFN it is possible to infer possible high-connectivity locations in the fractured ice volumes and their location at the surface (figure 2b). Further quantitative analysis work on the DFN and the volume of ice will allow to simulate the movement along the major structures backwards and forward in time in order and to capture the strain in the ice volume by incorporating its rheological parameters, and also test the transpression vs necking approach. The 3D geomodelling approach appears as a promising tool not only for scientific analysis but also to identify interesting target of future JUICE observation, where resurfacing or deep fluid expulsions could be more favored. Figure 1: a) The structural map by[4] with the families of grooves (GUS). In b) the 3D geometric reconstruction of the larger GUS1 structures. This analysis is focused in the white box Figure 2: In a) the modelled DFN with the three families of major structures and in b) voxel-based volume showing areas at higher connectivity. Acknowledgements: The activity has been realized under the ASI-INAF contract 2018-25-HH.0. References: [3] Pizzi, A., Domenica, A.D., Komatsu, G., Cofano, A., Mitri, G., Bruzzone, L., 2017. Spreading vs. Rifting as modes of extensional tectonics on the globally expanded Ganymede. Icarus 288, 148–159. https://doi.org/10.1016/j.icarus.2017.01.034 [4] Rossi, C., Cianfarra, P., Salvini, F., Mitri, G., Massé, M., 2018. Evidence of transpressional tectonics on the Uruk Sulcus region, Ganymede. Tectonophysics 749, 72–87. https://doi.org/10.1016/j.tecto.2018.10.026 [1] Lucchetti, A., Rossi, C., Mazzarini, F., Pajola, M., Pozzobon, R., Massironi, M., Cremonese, G., 2021. Equatorial grooves distribution on Ganymede: Length and self-similar clustering analysis. Planetary and Space Science 195, 105140. https://doi.org/10.1016/j.pss.2020.105140 [2] Pappalardo, R.T., et al., 1998. Grooved Terrain on Ganymede: First Results from Galileo High-Resolution Imaging. Icarus 135, 276–302. https://doi.org/10.1006/icar.1998.5966 [7] Pozzobon, R., Penasa, L., De Toffoli, B., Rossi, A. P., & Massironi, M. (2020). 3D geo-models based on multiple datasets on Mars (implicit or explicit modelling) (Public D6.1; Planmap Deliverable). [8] Penasa, L., Pozzobon R., Rossi, A. P., Massironi, M., (2020), 3D geo-models based on multiple datasets on the Moon (implicit or explicit modelling) (Public D6.2; Planmap Deliverable). [9] Pozzobon, R., Penasa, L., Massironi, M., Ferrari, S., (2021) 3D geo-models based on multiple datasets on Mercury (explicit modelling) (Public D6.3; Planmap Deliverable). [6] Massironi, M., Rossi, A. P., and the PLANMAP Consortium, PLANMAP Final report 2021 [5] Massironi, M. et al., 2018. Towards integrated geological maps and 3D geo-models of planetary surfaces: the H2020 PLANetary MAPping project, in: EGU General Assembly Conference Abstracts, EGU General Assembly Conference Abstracts. p. 18106. [10] Zubarev, A., Nadezhdina, I., Brusnikin, E., Giese, B., Oberst, J., 2017. A search for Ganymede stereo images and 3D mapping opportunities. Planetary and Space Science 146, 40–54. https://doi.org/10.1016/j.pss.2017.07.021

Rembrandt is a 715 km-diameter basin on Mercury centered at 32.89°S latitude and 87.86°E longitude. This crater constitutes a remarkable example of the stratigraphic variability on Mercury. The uppermost smooth plains of volcanic origin, which are temporally unrelated to the impact event, have been distinguished by the surrounding smooth plains utilizing spectral information. The basin is crosscut by a prominent NE-SW thrust system more than 1000 km long, named Enterprise Rupes (Ferrari et al., 2015; Galluzzi et al., 2015; Semenzato et al., 2020), attributed mainly to crustal shortening induced by global contraction (see Semenzato et al., 2020 and references therein). This consists of a set of lobate scarps and wrinkle ridges with inverse to transpressional kinematics (Massironi et al., 2015). The aim of this work, as part of the PLANMAP Horizon 2020 project, is to use all the available information on the site to provide a comprehensive 3D model of both the structural setting and the thicknesses of the main units of the Rembrandt basin infilling using explicit modeling approach. The principle of three-dimensional explicit modelling relies on the creation of 3D surfaces based on geologic observations and constraints. While implicit modelling and its effectiveness rely on the amount of available data both on the surface and the subsurface to provide a mathematical solution that satisfies all the constraints, the explicit geological modelling implies a more extended geologic interpretation based on the available data which is subject to the operator’s experience and is essentially based on the construction of several interpreted cross-sections to be then interpolated generating mesh surfaces. The advantage is that such type of geologic modelling can be applied in areas with scarcity of data, especially related to subsurface constraints. In the case of the Rembrandt basin, we mainly based our reconstruction on the geo-stratigraphic map and geologic cross-section from Semenzato et al. (2020). Additional constraints, regarding fault kinematics and fault plane geometry, were provided by Galluzzi et al. (2015) and Crane (2020). As a basemap, we used the MESSENGER MDIS global mosaic at 166 m/pixel together with the MDIS global DEM (665 m/pixel), both of them available in the USGS repositories, with the same Lambert Conformal Conic (LCC) projection of the geo-stratigraphic map. In Rembrandt basin two different infillings - the YIP (Young Interior smooth Plains) and OIP (Older Interior smooth Plains) units - overlay the IT (para-autochtonous intracrater plains) base unit. The thickness of these units was estimated with several methods in Semenzato et al., (2020), among which the presence of impact craters excavating and exposing the inner basin stratigraphy. We used such craters for the construction of the interpreted cross-sections in complement to the one by Semenzato et al., (2020). These were subdivided into two intersecting sub-parallel sets. The interpreted subsurface horizons were used for mesh interpolation together with the geologic contacts between the different units on the surface creating meshes representin ghte top of the YIP, OIP and IT basin infilling units. The volume between them was then calculated. The structural modelling was carried out using the structural mapping from Semenzato et al., (2020) and Ferrari et al., (2015). The faults’ vergence and their angles were extracted both thanks to the illumination conditions on the image mosaic and topography, to the measurements provided by Galluzzi et al., (2015) on displaced impact craters and to the work by Crane (2020) and Massironi et al., (2015). This way we were able to model the Enterprise rupes thrust geometry, its splays and backthrusts as well as contractional lobate scarps and extensional radial features within the basin infilling units. Although requiring a certain degree of assumptions especially on planetary bodies, the 3D geomodelling proves to be a useful tool in order to check surface interpretations that might change once set into 3D environment and refine volume calculations and 3D shape of geologic units. Follow up investigations will focus on forward and backwards modeling work on the activity of the Enterprise Rupes system. Figure 1: in a) the mesh construction for the main Enterprise rupes structure, constrained with surface mapped lineaments and anchored on the geologic cross-section. In b) the tetrahedral volumetric mesh representing the two events of Rembrandt basin infilling. In c) the structural and stratigraphic geomodel of Rembrandt basin (https://skfb.ly/6ZqtI). Acknowlegements: This research was supported by the European Union’s Horizon 2020 under grant agreement No 776276‐PLANMAP. References: Crane, K., 2020. Structural interpretation of thrust fault-related landforms on Mercury using Earth analogue fault models. Geomorphology 369, 107366. https://doi.org/10.1016/j.geomorph.2020.107366 Ferrari, S., Massironi, M., Marchi, S., Byrne, P. K., Klimczak, C., Martellato, E., & Cremonese, G. (2015). Age relationships of the Rembrandt basin and Enterprise Rupes, Mercury. Geological Society, London, Special Publications, 401(1), 159–172. https://doi.org/10.1144/SP401.20 Galluzzi, V., Di Achille, G., Ferranti, L., Popa, C., & Palumbo, P. (2015). Faulted craters as indicators for thrust motions on Mercury. Geological Society, London, Special Publications, 401(1), 313–325. https://doi.org/10.1144/SP401.17 Massironi, M., Di Achille, G., Rothery, D. A., Galluzzi, V., Giacomini, L., Ferrari, S., Zusi, M., Cremonese, G., & Palumbo, P. (2015). Lateral ramps and strike-slip kinematics on Mercury. Geological Society, London, Special Publications, 401(1), 269–290. https://doi.org/10.1144/SP401.16 Semenzato, A., Massironi, M., Ferrari, S., Galluzzi, V., Rothery, D. A., Pegg, D. L., Pozzobon, R., & Marchi, S. (2020). An Integrated Geologic Map of the Rembrandt Basin, on Mercury, as a Starting Point for Stratigraphic Analysis. Remote Sensing, 12(19), 3213. https://doi.org/10.3390/rs12193213

Introduction: The Space Science Data Center (SSDC) developed MATISSE (Multi- purposed Advanced Tool for the Instruments for the Solar System Exploration, [1]) webtool, whose v2.0 update [2] is available at https://tools.ssdc.asi.it/Matisse/, which allows access to data of the planetary exploration missions. The MATISSE tool uses some protocols provided by the Virtual European Solar & Planetary Access (VESPA), including EPN-TAP, and allows access to a series of services without necessarily having to download the data, but view the maps directly online. In this context the work here presented points at improving and expanding the functionalities of the MATISSE tool to the planetary geology, by including some already published geological maps. These will be essential in order to make MATISSE a useful tool for the analysis of planetary surfaces. MATISSE for planetary geology: The geological maps involved in this project will be of fundamental help to the scientific community in the geological characterization of landing sites and to obtain useful information for the study of planetary bodies surface. The good choice of the landing site, which satisfies both engineering and scientific requirements, represents one of the key points for the success of a space mission. For example, the identification of landing sites, of particular geological / mineralogical interest, will be carried out thanks to data fusion techniques between visible images and infrared spectroscopic measurements. The tool in question will give the user the opportunity to observe the area in question integrating data of multiple sources. MATISSE will also be able to carry out geomorphological analysis and morphometric products (e.g. slopes, relief, roughness index) which will allow a complete investigation both from the geological and engineering point of view. The geological maps will be integrated with mineralogical maps, obtained using infrared spectroscopic data. In collaboration with PlanMap and GMap teams we are currently working to include Martian, Hermean and Cerean surfaces so that both recently ended missions (e.g., NASA’s Dawn) and missions still not in their scientific phase (e.g., ESA’s BepiColombo) would benefit for this work. Work methodology: The geological maps of interest will be downloaded in appropriate format, so that every polygon representing a geological unit can be separately inserted into the geospatial database of MATISSE and be easily retrieved by the user. In particular, the user can choose one or more of the polygonal units as input for the geographical query after selecting the target and the instruments of interest. In this way the MATISSE capabilities can be fully exploited even trough geological oriented requests. Here are some examples of areas that we have analyzed on the Martian surface, with the collaboration of the PLANMAP team. These sites, Firsoff Crater and Commelin Crater, are located in Arabia Terra region. After a careful geological analysis of the two craters, similar morphological characteristics were identified [3]. After starting the query, the user will see the area with the selected lithologies displayed (figure 1) and can carry out appropriate analyzes. Expected outcomes: We plan to make available the first release of MATISSE with geological maps in the next months, even if starting with only limited capabilities. The inclusion of these functionalities in the tool could produce a sensible step forward in the study of planetary geology, with the possibility of better exploiting different datasets and taking also into account the collaboration of different teams already leaders if this field. Another goal will be to expand the use of the tool, making it similar to the Geographic Information System (GIS). We will expand the possibility of selecting specific areas to be analyzed on the base of the geographical position of the data and the pertinence to specific geological units. It will be also possible to obtain topographic profile and select multiple data to be simultaneously observed. All these analyzes will be performed directly on 3D models. References: [1] Zinzi A. et al. (2016) Astron. Comput., 15, 16-28. [2] Zinzi A. et al. (2019) EPSC-DPS Joint Meeting 2019, id. EPSC-DPS2019-1272. [3] Pondrelli M. et al. (2010) Earth and Planetary Science Letters, 304, 511-519.