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Avec plus d’un an de retard suite à la crise COVID (Anthropocène supérieur), nous présentons ici un squelette partiel d’un hibou fossile de grande taille qui entretemps a déjà été publié (Mayr et al., 2020). Ce retard n’est toutefois pas réellement préjudiciable étant donné que le spécimen a été découvert il y a déjà plus de 30 ans dans les couches du Wasatchien moyen (Wa-3) de la Formation de Willwood à McCullough Peaks, au Wyoming (USA), permettant ainsi de le dater entre 54,5 et 55,0 Ma (début de l’Eocène inférieur). Le spécimen inclut la majorité des os postcraniens d’un des strigiformes fossiles les plus complets du Paléogène. Primoptynx poliotaurus mesurait environ 50 centimètres de long, taille comparable à Hedwig, le harfang des neiges de Harry Potter, et appartient à un groupe de hiboux proche de la famille éteinte des Protostrigidae, bien que ne partageant pas avec ces derniers la morphologie dérivée du tibiotarse. Les pattes de Primoptynx sont différentes de celles des strigidés actuels (hiboux et chouettes). Les hiboux ont aujourd'hui quatre doigts avec des griffes de même taille pour attraper des proies relativement petites, et les tuer avec le bec. Primoptynx a les premier et second doigts plus longs, comme on le voit chez les éperviers, buses, aigles et autres membres de la famille des Accipitridae. Ces deux doigts plus développés sont utilisés pour épingler les proies, qui sont dès lors percées par les serres. Primoptynx était donc un hibou qui chassait comme un aigle, des mammifères de taille moyenne. Ce fossile montre, avec d’autres découvertes, que durant l’Eocène inférieur il y avait déjà une certaine diversité de strigiformes, de différentes tailles, qui occupaient diverses niches écologiques. Le succès des hiboux allait de pair avec celui des mammifères, devenus très diversifiés à l’Eocène inférieur. L'extinction ultérieure de Primoptynx et d'autres proto-hiboux pourrait être due à l'émergence d'oiseaux de proie diurnes à l'Éocène supérieur. Financements Cette étude a été menée dans le cadre du projet BR/121/A3/PalEurAfrica, financé par la Politique Scientifique Fédérale Belge. Références Mayr G., Gingerich P.D. & Smith T., 2020. Skeleton of a new owl from the early Eocene of North America (Aves, Strigiformes) with an accipitrid-like foot morphology. Journal of Vertebrate Paleontology, 40(2):e1769116. https://doi.org/10.1080/02724634.2020.1769116.

One of the greatest challenges of the last decades in the fight against climate change has been to achieve net-zero emissions by mid-century. According to the US EPA (2016), in 2014, global anthropogenic emissions of carbon dioxide (CO2) accounted for ~64% of the greenhouse effect. Carbon dioxide capture and storage (CCS) plays an irreplaceable part as a mitigation technology that avoids CO2 emissions at their source and bridges the transition into a non-carbon-based energy future. The International Energy Agency (IEA) estimates that the need to store CO2 will grow from 40 Mt/y at present to more than 5000 Mt/y by 2050. Additionally, in the IEA’s Sustainable Development Scenario, which aims for global net-zero CO2 emissions from the energy sector by 2070, CCS needs to become a global industry supporting emissions reductions across the overall energy system. CCS technologies essentially consist of capturing and compressing the CO2 at the source and then transport it towards deep suitable rock formations where it is injected to be permanently stored. The key to successful and permanent CO2 storage is the proper analysis and characterization of the reservoir and seal formation. Among the types of reservoir suitable for CO2 storage are unmined coal beds, depleted oil and gas fields, EOR/EGR, saline aquifers, man-made caverns, and basaltic formations (IPCC, 2005). The storage capacity of any of these reservoirs is the subsurface commodity whose quantities and properties are assessed when existing data is provided. Capacity estimations bring their own level of uncertainty and complexity according to the scale at which they are addressed and the nature of the geological conditions of the reservoir. This degree of uncertainty should be accounted for in every estimation (Bradshaw et al., 2007) Resource classification systems (RCS) are frameworks that establish the principles and boundaries for each level of capacity assessment. By making use of these frameworks, it is possible to properly allocate the stage of development of a resource (United Nations, 2020). For every level of assessment, the principles of the estimation change and so do the scale and purpose. As the analysis moves forward, a prospective site develops and exhaustive information is acquired, initial estimations are adjusted, and uncertainty is likely to reduce. Additionally, different economic, technical, regulatory, environmental and societal factors are integrated into the assessment to bring the estimations under present conditions. For instance, if the storage capacity is to be matched with a CO2 source, detailed simulations and analyses regarding injectivity, supply rate, potential routes and economic distances must be performed to achieve a realistic estimation. However, an assessment where the main goal is to merely quantify the space available to store CO2 in a reservoir, does not consider the aforementioned limitations and will carry higher risk and uncertainty in its estimation (Bradshaw et al., 2007). Even though resource classification systems provide a solid foundation for CCS projects, they do not provide the input parameters and analyses needed to reach every level of assessment. This is why storage capacity estimation methodologies go hand in hand with RCS given that the former can give information related to the parameters and constraints considered in the estimation. No standard process has been proposed that can be followed from the starting level of a CO2 storage capacity assessment until a fully developed carbon storage resource; that is, a CO2 storage site ready to become fully operational. This paper aims to develop a methodology where the fundamental steps needed to go through every level of the resource classification systems are standardized. This methodology intends to serve as a general baseline that, regardless of the geological settings and techno-socio-economic conditions, can be adopted for any CCS assessment. The proposed methodology is built by reviewing the available capacity estimation methods for every level of assessment and identifying social, technical and economic aspects that come into play as the resource is being developed. Considering that capacity estimation methodologies can vary their approach even for the same level of assessment, the rationales behind them are expected to be determined. Such rationales can be related to in-place policy restrictions, geographical economic behavior, or the nature of the parameters contemplated. Additionally, PSS, an in-house developed tool that can assess CO2 storage reservoirs at different levels, will be proposed within the methodology. This tool is a bottom-up geotechnical and economic forecasting simulator that can generate source-sink matching for CCS projects, where technical, economic, and geological uncertainties are handled through a Monte Carlo approach for limited foresight (Welkenhuysen et al., 2016). Acknowledgements This research is carried out under the LEILAC2 project, which receives funding from the European Union’s Horizon 2020 research and innovation program under grant agreement number 884170. The LEILAC2 consortium consists of: Calix Europe SARL, HeidelbergCement AG, Ingenieurbüro Kühlerbau Neustad GmbH (IKN), Centre for Research and Technology Hellas (CERTH), Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Politecnico di Milano (POLIMI), Geological Survey of Belgium (RBINS-GSB), ENGIE Laborelec, Port of Rotterdam, Calix Limited, CIMPOR-Indústria de Cimentos SA and Lhoist Recherche et Development SA. References Bradshaw, J., Bachu, S., Bonijoly, D., Burruss, R., Holloway, S., Christensen, N. P., & Mathiassen, O. M. (2007). CO2 storage capacity estimation: Issues and development of standards. International Journal of Greenhouse Gas Control, 1(1), 62–68. https://doi.org/10.1016/S1750-5836(07)00027-8 IPCC. (2005). Carbon Dioxide Capture and Storage. https://www.ipcc.ch/report/carbon-dioxide-capture-and-storage/ United Nations. (2020). United Nations Framework Classification for Resources: Update 2019. UN. https://doi.org/10.18356/44105e2b-en US EPA. (2016). Global Greenhouse Gas Emissions Data. US EPA. https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data Welkenhuysen, K., Brüstle, A.-K., Bottig, M., Ramírez, A., Swennen, R., & Piessens, K. (2016). A techno-economic approach for capacity assessment and ranking of potential options for geological storage of CO2 in Austria. Geologica Belgica. http://dx.doi.org/10.20341/gb.2016.012

The battery market for electric vehicles and renewable energy storage is dominated by rechargeable lithium-ion batteries, making lithium supply essential to climate action through decarbonization. In 2019, more than half of the world's lithium was sourced from lithium pegmatites of the Li-Cs-Ta (LCT) family, predominantly from Australia. Current global lithium supply involves long diesel-fueled maritime transport routes, which counteracts lithium's role in climate action. Responsible consumption and production require shorter supply chains from deposit to battery. Reading the mineralogical record of LCT pegmatite deposits can help address the challenge of reducing the climate impact of lithium production, by informing deposit models, mineral exploration, and geometallurgy, therefore promoting local supply. Our research focuses on a belt of LCT pegmatites, which is located along the eastern margin of the late-Caledonian S-type Leinster Batholith, southeast Ireland. The LCT pegmatites are hosted by a major regional shear zone and are part of a tin-lithium province that stretches subparallel to the Iapetus suture from Europe through Nova Scotia to North and South Carolina. We investigated crystal chemical zoning in muscovite, cassiterite, and columbite-tantalite using petrography, scanning electron microscopy, and LA-ICP-MS chemical mapping. The zoning patterns record that pegmatite rare element mineralization resulted from an interplay of magmatic crystallization, metasomatism, and hydrothermal processes. Late-stage metasomatic alteration led to partial resorption of early minerals including the lithium ore-mineral spodumene, followed by dispersion of lithium and other rare elements into country rocks, mostly within dark mica. Dispersion led to formation of geochemical halos around the LCT pegmatites with the potential to use country-rock lithogeochemistry and mica composition as geochemical vectoring tools. Geochemistry of mica in the granite host analyzed by handheld LIBS has been found to exhibit coherent spatial patterns occurring adjacent to and above LCT pegmatites known at depth from drilling. These channels of mineral-specific geochemical information are distinct from soil geochemical patterns and are not influenced by the same secondary, surface processes such as dilution. As outcrop is virtually absent in the study area, regional stream sediment geochemistry data (Geological Survey Ireland) was assessed as an LCT pegmatite exploration tool. After correcting for geologic background using a linear regression approach, catchments containing LCT pegmatites show high residuals for concentrations of both tantalum and tin. The mineralogy of stream sediment samples from a subsample of these catchments was subsequently analyzed to characterize the host minerals of tin and tantalum. Cassiterite and columbite-tantalite were identified, and both show geochemical and textural signatures that correspond to the zoning patterns mentioned above, which indicates that these minerals were derived from the local LCT pegmatites. These results suggest that, when regional geology and tectonic setting are prospective, lithium pegmatite prospectivity can be further assessed for tin-tantalum associations in (often publicly available) regional stream sediment data. Following geospatial analysis, stream sediment samples could be obtained from individual prospective catchments and their mineralogy analyzed. Local-scale geochemical surveys could follow where stream sediments of prospective catchments contain tin and tantalum oxides with chemistries and textures indicative of a lithium pegmatite source.

From its foundation to its heydays as trading hub and to its final abandonment, the history of Charax Spasinou was intimately connected with the evolution of the river systems of the southernmost part of the Mesopotamian plain and the shoreline of the Persian Gulf. This ongoing research, which is part of the Charax Spasinou Project of the Universities of Konstanz and Manchester supported by the German Research Foundation and the Culture Protection Fund of the British Council, aims to reconstruct the evolution of the landscape and palaeoenvironment around the capital of Mesene, by combining evidence from remote sensing data and geological coring. Here, results from the analysis of satellite imagery and a preliminary field campaign carried out in 2018 will be presented. It will be demonstrated that a combined geological and archaeological survey in the wider hinterland of Charax allows an accurate reconstruction of the ancient watercourses and the landscape of Mesene, in which the capital was the nodal point for nearly a millennium.

The RESPONSE project aims at improving the use of coupled reactive transport models to simulate the fate of inorganic and organic contaminants within environments, characterised by a fluctuating shallow groundwater table – inducing strong hydraulic, physico-chemical and redox gradients. Three case studies were selected based on the presence of inorganic and/or organic contamination. Two sites are cemeteries where groundwater pollution by herbicides (2,6-dichlorobenzamide (BAM) – a persistent metabolite of herbicide dichlobenil) was detected. Top soil and groundwater samples were collected and the BAM degradation and mineralization potential of soil microbiota is tested in the laboratory. It is hypothesized that BAM degradation is strongly affected by DOC quality (measured through specific UV absorbance) and quantity. RESPONSE will investigate whether predictions of dichlobenil and BAM migration in soils and groundwater can be improved by taking into account DOC quality/quantity.The third site is a former municipal landfill, where redox zonation and contamination by As is observed. This site is primarily used to study the level of hydrogeological and geochemical detail needed to predict the migration of pollutants in a satisfactory way. This hypothesis is tested by comparing predictions using site specific measured parameters (soil and subsoil hydraulic parameters, in-situ groundwater flow characterization, etc.) with predictions using parameters inferred from existing hydrological/ geochemical data available in data bases. Moreover, an integrated tool is developed to simulate water flow and reactive solute transport in the subsurface focusing on the water table interface. This is achieved by loosely coupling the existing HYDRUS, MODFLOW, MT3D-USGS and PHREEQC codes at the lowest level and adding functionalities for the transfer of solute concentrations. The HYDRUS package for MODFLOW (Seo et al., 2007) has been updated and PHREEQC functionalities are coupled to both the unsaturated zone (based on HPx software; Jacques et al., 2018) and the saturated zone.

Nowadays we are faced with several challenges regarding mineral exploration and exploitation in Europe. The biggest accessible deposits have already been discovered and exploited, with some of those mines dating back of thousands of years. What remains now are the small and difficult to access deposits, leading to the needs of new and more sustainable mining methods. In the last years several projects like ROBOMINERS were started with the expectation to have relevant impact in social, technological, environmental and economical areas and aiming to help in (i) reducing EU dependency on import of raw materials, (ii) pushing the EU to the forefront in sustainable minerals surveying and exploration technologies and to (iii) improve resource efficiency and responsible sourcing. The main objective of the ROBOMINERS project is to develop a Bio-Inspired, Modular and Reconfigurable Robot Miner, equipped with selective mining perception and mining tools for small and difficult to access deposits. A consortium that includes geoscientists, roboticists and engineers is working to build a modular robot prototype (Technology Readiness Level 4 to 5), design a new mining system via simulation and modelling and to use the prototype to study and advance future research on different areas of robotics and raw materials alike (Lopez and al. 2020). ROBOMINERS will not reach its end-state by the end of the project. Therefore, it already prepares future development with visions for 2030 and 2050, coinciding with important EU targets (2030: reduce GHG emissions, more renewable energy; 2050: climate neutrality). These visions will impact the developments of robotics, selective mining and mining ecosystem. The considered methods and tools, although innovative at this point, will be continuously assessed, and compared to new technology developments in the relevant fields. The ROBOMINERS project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 820971. References. L. Lopes, B. Bodo, C. Rossi, S. Henley, G. Žibret, A. Kot-Niewiadomska, V. Correia, ROBOMINERS – Developing a bio-inspired modular robot-miner for difficult to access mineral deposits, Advances in Geosciences, Volume 54, 2020, 99–108