The origin of titanium-rich basaltic magmatism on the Moon remains enigmatic. Ilmenite-bearing cumulates in the lunar mantle are often credited as the source, but their partial melts are not a compositional match and are too dense to enable eruption. Here we use petrological reaction experiments to show that partial melts of ilmenite-bearing cumulates react with olivine and orthopyroxene in the lunar mantle, shifting the melt composition to that of the high-Ti suite. New high-precision Mg isotope data confirm that high-Ti basalts have variable and isotopically light Mg isotope compositions that are inconsistent with equilibrium partial melting. We employ a diffusion model to demonstrate that kinetic isotope fractionation during reactive flow of partial melts derived from ilmenite-bearing cumulates can explain these anomalously light Mg isotope compositions, as well as the isotope composition of other elements such as Fe, Ca and Ti. Although this model does not fully replicate lunar melt-solid interaction, we suggest that titanium-rich magmas erupted on the surface of the Moon can be derived through partial melting of ilmenite-bearing cumulates, but melts undergo extensive modification of their elemental and isotopic composition through reactive flow in the lunar mantle. Reactive flow may therefore be the critical process that decreases melt density and allows high-Ti melts to erupt on the lunar surface.

Studio di stratigrafia integrata di una carota di sedimenti di 150 m recuperata a Brescia, presso il Parco delle Cave, nell'ambito delle attività del Foglio CARG 121 Brescia. Lo scopo dello studio è quello di caratterizzare la successione recuperata per ricostruzioni di tipo stratigrafico, paleodeposizionale e paleoambientale. Sono state riconosciute le principali discontinuità stratigrafiche di carattere regionale Y (0.45 Ma)ed R (0.87 Ma) che consentono di meglio tarare i principali rilfettori riconosciuti su una linea sismica adiacente all'area di studio.

Large Ca isotope variations recorded in mantle xenoliths and mantle-derived igneous rocks have been widely used to decode the origin of mantle heterogeneity, especially to trace recycled sedimentary carbonates. However, it is still unclear whether and how the subduction of sedimentary carbonate causes significant Ca isotope fractionation in the mantle in correspondence of convergent margins. In this study, we present Ca isotope data for sixteen silica-undersaturated ultrapotassic leucite-bearing rocks and their clinopyroxene (Cpx) phenocrysts from the "Colli Albani" volcano (Italy), and for six carbonate-bearing sediments from nearby Apennine Chain. These subduction-related volcanic rocks have been widely accepted as deriving from a mantle source that involves recycled carbonated sediments indicated by their enriched incompatible trace elements and radiogenic isotopes, and olivine geochemistry. The ?44/40Ca values (normalized to NIST SRM 915a) of leucite-bearing rocks are uniform (from 0.64 to 0.79 ?, with one exception of 0.86 ?) with an average of 0.72 ± 0.03 ?, 2SE, N = 16, which is 0.12 ± 0.03 ? (2SE) and 0.22 ± 0.03 ? (2SE) lower than MORBs (0.84 ± 0.02 ?, 2SE, N = 25) and BSE (0.94 ± 0.01 ?, 2SE, N = 14) respectively. In contrast, the carbonate-bearing sediments show variable and notably low ?44/40Ca values, ranging from 0.44 to 0.77 ?. The ?44/40Ca of Cpx (0.70 to 0.76 ?) is indistinguishable from their host rocks (0.73 to 0.76 ?). In addition, the lack of correlations between ?44/40Ca and SiO2, CaO, Ni and P2O5, and the Ca isotopic simulation result indicate that Ca isotope fractionation caused by fractional crystallization is insignificant. Given that the Ca isotope fractionation is limited during the melting of spinel wehrlite-like mantle source (within ~0.04 to 0.11 ?), the slightly low ?44/40Ca values of the Italian leucite-bearing rocks require 10 % to 20 % addition of carbonated sediments in their mantle source. This indicates that recycled carbonated sediments can cause slight ?44/40Ca heterogeneity (~0.1 to 0.2) of the mantle wedge in local/regional scales.

Radon is a radioactive gas and a major source of ionizing radiation exposure for humans. Consequently, it can pose serious health threats when it accumulates in confined environments. In Europe, recent legislation has been adopted to address radon exposure in dwellings; this law establishes national reference levels and guidelines for defining Radon Priority Areas (RPAs). This study focuses on mapping the Geogenic Radon Potential (GRP) as a foundation for identifying RPAs and, consequently, assessing radon risk in indoor environments. Here, GRP is proposed as a hazard indicator, indicating the potential for radon to enter buildings from geological sources. Various approaches, including multivariate geospatial analysis and the application of artificial intelligence algorithms, have been utilised to generate continuous spatial maps of GRP based on point measurements. In this study, we employed a robust multivariate machine learning algorithm (Random Forest) to create the GRP map of the central sector of the Pusteria Valley, incorporating other variables from census tracts such as land use as a vulnerability factor, and population as an exposure factor to create the risk map. The Pusteria Valley in northern Italy was chosen as the pilot site due to its well-known geological, structural, and geochemical features. The results indicate that high Rn risk areas are associated with high GRP values, as well as residential areas and high population density. Starting with the GRP map (e.g., Rn hazard), a new geological-based definition of the RPAs is proposed as fundamental tool for mapping Collective Radon Risk Areas in line with the main objective of Eu- ropean regulations, which is to differentiate them from Individual Risk Areas.

il volume presenta la sintesi dei percorsi e delle informazioni illustrate durante le escursioni del 18 e 20 maggio 2023 nell'ambito del Convegno dell'Associazione Italiana di Geologia e Turismo svoltosi nel sud della Sardegna

Il volume raccoglie i riassunti, i dati, le figure, le mappe e ogni altro materiale presentato al convegno dell'Associazione Italiana di Geologia e Turismo tenutosi a Cagliari il 18-20 maggio 2023

During the first two billion years the prokaryotes were the major form of life on Earth. These microorganisms dominated the Earth surface and played important roles in biogeochemical cycling and Earth and life evolu¬tion. Microbes have the potential to dissolve and precipitate minerals and also act on lithification processes. Therefore, understanding the mechanisms of biomineral formation and diagenesis will provide important insight concerning the role of microbes in mineral nucleation and growth. The approach which utilize modern environments, where biomineralization takes place, open the possibility to: 1) improve our understanding of the impact of life on the Earth's systems and its permanent imprint in the geological records and, 2) provide knowledge to be used in medical, environmental and materials sciences. An interdisciplinary investigation on modern carbonate hot spring systems (Tuscany, Italy) and sulphuric acid environment of an abandoned mine (Sardinia, Italy) have been performed. The unique occurrence of authigenic minerals in association with microbial communities in the study areas, acted as classical natural laboratories providing the opportunity to evaluate bio-geochemical and physicochemical factors that have direct influence in mineral precipitation. Using traditional and new tools from a sedimentary, petrographic, geochemical, mineralogical and geomicrobiological perspective integrated with high resolution techniques, it was possible to: 1) unequivocally identify different types of biominerals; 2) define their morphological features and composition linked to biotic compounds, 3) document nucleation processes, growth and diagenesis, and 4) provide 3D microscale visualization of the organomineral complex. This investigation confirms the existence of a direct link between biological activities, degradation of organ¬ic matter and biomineral formations. Filamentous bacteria, virus-like particles and extracellular polymeric substances are the main sites where minerals nucleate and grow. The very early stage of mineralization con¬sists into inorganic nanoparticles that gradually coalesce to form well-developed crystals. At larger scale, the microbial community interfaces with the environmental abiotic factors to form peculiar sedimentary bodies.

We explore the connections between crustal shortening, volcanism, and mantle dynamics in the Atlas of Morocco. In response to compressional forces and strain localization, this intraplate orogen has evolved far from convergent plate margins. Convective effects, such as lithospheric weakening and plume-related volcanism, contributed in important ways to the building of high topography. We seek to better understand how crustal and mantle processes interacted during the Atlas' orogeny by combining multiple strands of observations, including new and published data. Constraints on crustal and thermal evolution are combined with new analyses of topographic evolution, petrological, and geochemical data from the Anti-Atlas volcanic fields, and a simple numerical model of the interactions among crustal deformation, a mantle plume, and volcanism. Our findings substantiate that: (a) crustal deformation and exhumation accelerated during the middle/late Miocene, contemporaneous with the onset of volcanism; (b) volcanism has an anorogenic signature with a deep source; (c) a dynamic mantle upwelling supports the high topography. We propose that a mantle plume and the related volcanism weakened the lithosphere beneath the Atlas and that this favored the localization of crustal shortening along pre-existing structures during plate convergence. This convective-tectonic sequence may represent a general mechanism for the modification of continental plates throughout the thermo-chemical evolution of the supercontinental cycle

This report contains a progress update on the major achievements and challenges experienced so far for the Ministero dell'Università e delle Ricerche (MUR) regarding my Young Reseachers project.

This report contains updates for the European Research Council's Executive Agency on the major achievements and challenges experienced during the first half of my ERC Starting Grant project.

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The terrestrial planets are depleted in moderately volatile elements (e.g., K and Zn) relative to chondritic material. This depletion could be due to incomplete condensation or evaporative loss, either in precursor material or in accreting bodies. Potassium isotopes may distinguish between these different processes as they correlate with body mass, the smaller bodies being isotopically lighter (Tian et al., 2021), implying evaporative loss from the fully-formed bodies. However, the correlation of isotopic fractionation with elemental concentration is weak, and evaporative loss from a body as large as the Earth is challenging. In this work, we investigate how K loss and isotopic fractionation proceed during planetary growth, using a quantitative model of evaporative loss and a N-body accretion model. We consider adiabatic conditions for mass flux and equilibrium at the melt-vapour interface with a temperature-dependent partition coefficient and a constant isotope fractionation factor ?=0.99913. First, we model mass loss as a consequence of heating events (e.g. impacts) by elevating temperatures, and find that mass loss does not occur for bodies exceeding roughly 1023 kg (~1.5 lunar masses). Second, we study the potential for K loss driven by 26Al heating. Contrasting with previous work (Young et al, 2019), we find that temperatures buffer near the solidus with negligible evaporative loss and thus negligible isotopic fractionation, because once liquid-supported convection initiates, cooling rates exceed 26Al heating rates. Additional, rapid heating by e.g. impacts is thus required for significant evaporative loss from planetesimals. In ongoing work, we track potassium loss and isotopic fractionation over the course of N-body simulations of the runway and oligarchic stages of accretion. Preliminary results show a rough inverse correlation between body mass and isotope anomaly, implying that the observed correlation (Tian et al., 2021) could be a result of early evaporative loss followed by accretion, as well as mixing and dilution after overall mass loss ceases.

Different uncertainties sources affect the results of site response studies. Thus, the variability of the resulting synthetic hazard parameters should be modelized by considering appropriate probability distributions obtained by reproducing effects induced by stratigraphy and topography. Within this framework, a Project named PRIN SERENA aims at joining spatialized information (surface geology, topography), available over the whole Italian territory, with the outcomes of local surveys (shallow seismostratigraphic and geotechnical information after geognostic prospections) within a coherent frame. Particularly, a specific WorkPackage (WP3) is devoted to combining the effects of the velocity profiles variations and the variability in shear modulus reduction, G/G0 (?) and damping ratio, D(?) curves. Large scale extensive seismic microzonation studies have been explored for this purpose to properly aggregate information (Romagnoli et al., 2022; Gaudiosi et al., 2021). The present work provides insights from sensitive analyses carried out for prototypal sites in Italy and a state of art of the models obtained from the seismic microzonation studies to highlight the relevant geological and geophysical site signatures.

The creation of hazard maps relative to volcanic phenomena requires taking into account the intrinsic complexity and variability of eruptions. Here we present an example of how HPC can allow producing a high resolution multi-source probabilistic hazard assessment due to tephra fallout over a domain covering Southern Italy. The three active volcanoes in the Neapolitan area, Somma-Vesuvius, Campi Flegrei and Ischia, were considered as volcanic sources. For each one, we explored three explosive size classes (Small, Medium and Large) for Somma Vesuvius and Campi Flegrei, and one explosive size class (Large) for Ischia. For each size class, we performed 1500 numerical simulations of ash dispersion (total of 10500) using the Fall3D (V8.0) model over a computational domain covering Southern Italy with a 0.03° ? 0.03° (~3 km ? 3 km) resolution. Within each size class, the eruptive parameters have been randomly sampled from well-suited probability distributions and with different meteorological conditions, obtained by randomly sampling a day between 1990 and 2020 and retrieving the relative data from the ECMWF ERA5 database. This allowed exploring the intra-class variability and to quantify aleatoric uncertainty. The results of these simulations have been post-processed with a statistical approach by assigning a weight to each eruption (based on its eruption magnitude) and the annual eruption rate of each size class. For the case of Campi Flegrei, the variability in the eruptive vent position has also been explored by constructing a grid of possible vent locations with different spatial probability. By merging the results obtained for each source and size class we produced a portfolio of hazard maps showing the expected mean annual frequency of overcoming selected thresholds in ground tephra load. A disaggregation analysis has also been performed in order to understand which particular source and/or size class had the greater impact on a particular area. The completion of this work, considering both numerical simulations and the statistical elaboration of the results has required a total of more than 5000 core hours and the processing of more than 2TB of data, an effort that wouldn't have been possible without the access to high level HPC resources.

In recent decades, one of the most interesting innovations has undoubtedly been the application of resilience principles to the study and mitigation of seismic risk. However, although new rigorous mathematical models have become available in the context of seismic resilience assessment, their applications to real case studies focus on a local scale, or even single structures. Consequently, new models and procedures are absolutely necessary to adopt resilience measurements in the formulation of mitigation strategies on a national or subnational scale. Given the crucial role of residential buildings in the global resilience of Italian cities against major earthquakes, a new framework for large-scale applications is proposed to roughly measure the seismic resilience of communities through the integration of an empirical recovery function based on the reconstruction process of housing systems in the aftermath of the 2012 Northern Italy Earthquake. As a first attempt, the framework is applied to housing systems in the southern regions of Italy by modelling their physical damage with vulnerability curves defined on the basis of macroseismic approaches. The main results are presented and discussed in terms of average functionality levels over time in order to compare and understand the recovery capacity of the considered housing systems.

In this paper we show data from new detailed geological-structural field surveys, integrated with preliminary photogrammetric analysis, presented in a 1:10,000 scale geological map. The field-based investigations covered an area of about 60-km2, located at the southern termination of the Calabrian Forearc, in NE Sicily (Italy), at the intersection of two key regional-scale fault systems. These are represented by the Peloritani Sole-Thrust, along which the Kabilo-Calabride orogenic edifice overthrusted onto the Apenninic-Maghrebian Chain, and the Mt. Kumeta-Alcantara Line, which played a key role in the post-Oligocene evolution of the Nubia-Eurasia converging margin. The collected data permitted the recognition of a new terrigenous stratigraphic unit, the Malvagna Flysch, and the acquisition of updated structural information useful to better understand the kinematics of the easternmost portion of the Mt. Kumeta-Alcantara Line. The geological map provides new insights for the reconstruction of the geodynamic evolution of this sector of the Calabrian Forearc.

Introduction: The terrestrial planets are depleted in moderately volatile elements (MVEs) relative to chondritic material [1]. This depletion could be due to either incomplete condensation [2] or partial mass loss, either in precursor material or in accreting bodies. The Earth has an excess of the heavier Mg and Si isotopes [3], which may be due to evaporative loss caused by impact-driven melting during accretion [3] or by heating due to 26Al decay [4]. MVEs like potassium and zinc also show isotopic anomalies [5,6]. Potassium isotopes show a correlation with body mass [6], with the smaller bodies being isotopically lighter. This observation could imply evaporative loss from the fully-formed bodies. However, the correlation of isotopic fractionation with elemental concentration is weak, and evaporative loss from a body as large as the Earth is challenging [4]. In this work we apply a quantitative model of evaporative loss to potassium isotopes, coupling it with an N-body accretion model [7] to investigate how fractionation and loss proceed as planetesimals grow. Here we focus on the potential for loss driven by 26Al heating [4] rather than by impacts [3,8]. Evaporative Loss: We first explore mass loss for an array of initial accreting body conditions, with initial masses in the range 0.01-1.38x1023 kg corresponding to a range of radii from ~408 to ~2112 km. Evaporative mass loss from initially molten bodies occurs via hydrodynamic escape [3,4] with the surface pressure determined by the temperature of the molten interior. We consider both isothermal and adiabatic conditions for mass flux and elemental escape. The adiabatic mass loss rate is solved following [9]. The effective surface temperature of the molten body is determined by balancing the isoviscous convective and radiative heat fluxes [3] and the interior temperature decreases as the model run proceeds. To calculate the loss of potassium we assume a temperature-dependent partition coefficient. The isotopic evolution is then tracked assuming equilibrium fractionation at the melt-vapour interface [4] and a constant fractionation factor ?. Each simulation ends under one of two potential conditions. Either the magma ocean cools to its solidus, set at 1400 K, or the interior temperature drops to the point at which adiabatic escape is no longer energetically possible [10]. Either scenario results in mass loss ceasing. Realizations at each initial temperature were run for increasing body masses until negligible mass loss was achieved after the first time step. Figure 1. A. Fraction of potassium lost via hydrodynamic escape as a function of initial interior temperature and body mass. Here an adiabatic atmosphere with n=0.2 is assumed. B. Potassium isotope anomaly, assuming ?=0.99913. Single-body Results: Figure 1A shows the fraction of potassium lost for various initial body masses and internal temperatures. For high initial temperatures (above ~2750 K), all the potassium is lost. Mass loss does not occur for bodies exceeding roughly 1023 kg. We observe a maximum fraction lost at intermediate masses. This is because large bodies have a high gravity, impeding escape, while small bodies cool rapidly, limiting the time for escape to occur. Figure 1B shows that the ??41/39K is generally higher for higher initial temperatures and smaller masses, with again a maximum at intermediate masses where mass loss is most efficient. N-body Model: Planetary bodies grow by collisions, so that the final elemental and isotopic composition of an object is a mixture of the starting bodies' compositions. We use the approach outlined above and track the evolution of potassium as bodies collide, assuming simple mixing. That is, we assume all 54th Lunar and Planetary Science Conference 2023 (LPI Contrib. No. 2806) 1350.pdf potassium loss and fractionation happens early, as the bodies form, and that impact vaporization or mechanical erosion during subsequent collisions is negligible. For our accretion model we use output from [7] in which planetesimal growth through the runaway and oligarchic stages of accretion is tracked, and the influence of migrating giant planets is included. We assume that each starting body has an initial temperature set by heating due to 26Al decay. The accretion time is varied randomly from 0 to 2 Myr after CAI and the peak temperature is calculated accordingly, based on a decay constant of 0.99 Myr-1 and a temperature at 1 Myr of 1486 K. Mass loss for each body is then calculated assuming this initial temperature and an isothermal atmosphere. For the isotopic calculations a constant fractionation factor of ?=0.99913 is assumed. N-body Results: Figure 2. Potassium isotope anomaly vs. K/U ratio for bodies growing by collision according to [7]. Dot size is proportional to final mass; color indicates number of collisions. EPB=eucrite parent body. The dotted line indicates the expected results for pure Rayleigh fractionation. Figure 2 shows the calculated ??41/39K against the K/U ratio of the final objects, where the colors indicate the number of impacts. Bodies that suffer no impacts follow the Rayleigh fractionation line (dotted), where more significant K loss results in larger isotopic anomalies. Larger bodies typically show more subdued isotopic anomalies due to mixing and dilution. Figure 3. Potassium isotope anomaly as a function of final body mass. Color scheme as for Figure 2. Figure 3 shows the calculated ??41/39K against the mass of the final objects. The upper envelope of possibilities shows a rough inverse correlation (ellipse) between ??41/39K and mass, similar to the trend observed by [6]. Initial mass loss and fractionation is easier for smaller bodies, and smaller bodies are also less subject to subsequent dilution and mixing by later impacts. Thus, the trend observed by [6] does not necessarily imply that evaporative mass loss had to take place after accretion had finished; this signature could instead be a result of early evaporative loss followed by accretion, mixing and dilution. Future Work: Rather than simply specifying an initial temperature, a more realistic approach would be to track the internal temperature evolution due to the combined effects of 26Al heating, mass loss and radiative cooling. Tracking additional MVEs, such as Zn, would provide additional constraints. Experimental determination of the relevant ? values is desirable. Conclusions: Small, initially molten bodies develop large potassium anomalies via evaporative loss (Fig 1). Subsequent mixing and dilution during accretion can retain an inverse correlation between body mass and isotope anomaly (Fig 3), as observed.

Several studies suggested that the Mo isotope composition of Earth's mantle may be subtly sub-chondritic [1,2]. This observation cannot be reconciled with a likely barely detectable enrichment in heavy Mo isotopes in Earth's mantle following core-mantle differentiation [3]. A study of the Mo isotope composition of Earth's crust suggested it may be super- chondritic [4]. Complementarity between Mo isotopes in Earth's crust and mantle implies that Mo isotopes can provide valuable insights into the evolution of Earth's mantle-crust system. However, a sub-chondritic Mo isotope composition of the accessible mantle is debated. Given the incompatibility of Mo, mid-ocean ridge basalts (MORB) are arguably the most obvious type of rocks to study the Mo isotope composition of the mantle. Two previous studies yielded variably sub-chondritic to super-chondritic Mo isotope compositions in MORB [1,2], with no obvious systematics to explain the variability. More recently, a study focussed on enriched MORB, i.e. (La/Sm)N > 1, suggested they obtained higher Mo isotope ratios following metasomatism of mantle lithosphere caused by low degree partial melts derived from the mantle [5], thus explaining some of the variability in MORB. We analysed depleted MORB, i.e. (La/Sm)N < 1, from the Pacific, Indian and Atlantic oceans to determine their Mo isotope compositions and estimate a value for the bulk mantle. Our samples are characterised by sub-chondritic Mo isotope compositions on average, and none of the individual depleted MORB display super-chondritic values. Combined with literature data, we find that the bulk, accessible mantle is on average slightly sub-chondritic. Modelling suggests that >1 billion years of plate tectonic cycling of dehydrated, subducted oceanic crust into the mantle can explain the evolution of the mantle Mo isotope and Ce/Pb ratios in tandem, which is not the case for extraction of mantle partial melts. Our results thus add to the notion that the depleted mantle has been extensively modified by subduction-processed, oceanic crust.