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International audience; Recent investigations have shown that the continental shelf west of Ireland contains sedimentary landforms recording occupation by grounded, lobate ice sheet margins that extended from Ireland during at least the last glacial cycle. This paper reviews some of the offshore evidence of past glacial events available from high-resolution bathymetry, 2D/3D seismic datasets (Fig. 1), and shallow sediment cores providing information on the sedimentology, rheology and age of glacigenic stratigraphic units. The available data suggest that the continental shelf has been repeatedly occupied by tidewater ice margins characterised by ice streaming, possibly since the mid-Pleistocene transition. The offshore record provides as yet incomplete information on the extent and timing of glaciation from multiple centres of dispersal in Ireland. The dynamics of former ice sheets in Ireland, downwind of the climatically important central North Atlantic region, makes them of wider interest in the study of partially marine based ice sheet-ocean interactions in rapidly changing environments.

International audience; Ice sheets have occupied the Atlantic continental margin of Europe as far south as the Celtic Sea, where the maximum extent of glaciation remains in question. The Celtic Sea contains no obvious glacial landforms, but is dominated by a system of shelf-crossing seafloor megaridges, up to 60 m high and 10 km wide, that extend seaward up to 300 km in water depths of 100-200 m. The last British-Irish Ice Sheet (BIIS) was thought to have reached a limit on the mid-shelf, based on glacigenic sediments sampled on and between megaridges in the Irish-UK sectors, but recent work in this area has shown that the BIIS extended at least 150 km farther, at minimum to the UK shelf edge at 48˚20'N. Stratigraphic analysis of newly acquired core and seismic data has indicated the megaridges to be eroded sand bodies, which can be interpreted as a) glaciofluvial ridges modified by post-glacial megatides, or b) tidal banks truncated by wave energy. Here we examine megaridge morphology using a regional bathymetric grid and multibeam data across a 25x100 km area of the mid-shelf. At regional scale, the megaridges fan seaward to meet the shelf edge near-transversely along 600 km of its length, their axes rotating by 80˚ from W-E (Irish shelf) to almost N-S (French shelf). The fan-shaped network points to an apex in the north Celtic Sea, yet axial convergences are more common to seaward than landward. Individual megaridges consist of segments tens of kms long, of differing orientation, that form bathymetric highs. On the Irish-UK mid-shelf, multibeam imagery show that en echelon megaridge segments (up to 40 km long, 7 km wide, 55 m high) give way both axially and laterally to transverse 'ribs' (up to 10 km long, 10 m high). The ribs vary in form and spacing, distinct from asymmetric regularly-spaced sand waves within the multibeam data. Glacigenic sediments have been reported near seabed on and between both the megaridges and ribs, but subglacial lineations are not observed at seafloor. We hypothesise that the rectilinear network of megaridges and ribs are the eroded remnants of giant eskerine ridges flanked by glaciofluvial De Geer moraines, formed time-transgressively along an ice sheet margin during its retreat from the shelf edge. If correct, this interpretation would have broad implications for the dynamics of the last BIIS, and for the supply of meltwater and sediment across the shelf and slope to the North Atlantic at the LGM. Glaciofluvial vs tidal models for the formation of Celtic Sea bedforms invite testing through the targeted acquisition of core data, notably from areas of existing multibeam data in both the Irish-UK and French sectors.

International audience; An integrated geophysical, geological, and geochemical investigation of seabed fluid venting was carried out in upper Bantry Bay, a large marine inlet on the southwest coast of Ireland. The results provide evidence of the seafloor venting of gas rich fluids, resulting in the formation of a pockmark field identified here for the first time. The pockmarks occur in an area where sub-bottom profiles provide evidence of chimney-like features interpreted to record upward gas migration through Quaternary sediments to the seafloor. Three vibrocores up to 6 m long were acquired in water depths of 24-34 m, two from the pockmark field and one from outside. Methane of predominantly biogenic origin was quantified in all three cores by headspace analysis of sediment sub-samples. Well-defined sulfate methane transition zones (SMTZs) were observed in two of the cores, the shallowest (1.25 m) inside the pockmark field and the other (3.75 m) outside. It is likely that an SMTZ occurs at the location of the third core, also within the pockmark field, although beneath the samples obtained during this study. Gas release possibly from a combination of various faulting mechanisms and shallow methanogenesis appears to drive diffuse pore fluid migration across wide areas, while focused flow through the pockmarks may be related to gas originating from the Owenberg River Fault and methanogenesis of pre-glacial lacustrine sediments preserved in a bedrock basin. Analysis of phospholipid fatty acids (PLFAs) and archaeal isoprenoid hydrocarbons was used to investigate the microbial ecology of these sediments. Anaerobic oxidation of methane (AOM) may play a role in controlling release of CH4 to the water column and atmosphere in this shallow gas setting, potentially mediated by syntrophic sulfate reducing bacteria (SRB) and anaerobic methanotrophic archaea (ANME).

International audience; The Geological information and modelling Thematic Core Service (TCS) of EPOS is designed as an efficient and sustainable access system for geological multi-scale datasets for EPOS. The TCS develops and benefits from the synergy between the existing data infrastructures of the Geological Surveys of Europe (EuroGeoSurveys / EGDI) and the large amount of information produced by the research organizations and the international drilling community. The integration of distributed infrastructure components allows a broad range of resources including: geological maps, borehole data, borehole associated observations (borehole log data, groundwater level, groundwater quality…) and archived information on physical material (samples, cores), geological models (3D, 4D), geohazards, geophysical data such as active seismic data and other analyses of rocks, soils and minerals. In this presentation, we focus on the European Borehole Index and the work done since the beginning of the project, first to specify an interoperable data exchange mechanism based on international standards (such as INSPIRE, OGC) implemented by all TCS data providers. Then to collect this information from the data provider, quality check and disseminate it from the TCS Central Node as a service provider to the EPOS community using the same interoperable standards. We will develop on the problems encountered to manage large amount of data and the solutions we tested and applied. We will present how the Borehole Index was specified in order to guarantee its compliance with INSPIRE European Directive and how the OGC community was engaged to improve and promote technologies for geoscience data description and sharing through its Geoscience Domain Working Group. In addition, we will present expected workflows for the integration of other existing and new data such as 3D/4D models and how our work fits in EPOS system to create an efficient and comprehensive multidisciplinary research platform for the Earth Sciences in Europe and abroad.

Significant volumes of research over the past four decades has sought to elucidate the social, infrastructural, economic, and human health effects of climate change induced surface flooding. To date, epidemiological and public health studies of flooding events have focused on mental health effects, vector-borne diseases, and infectious enteric disease due to floodwater contact (i.e. typically low consumption rates). The inherent nature of groundwater (i.e. out of sight, out of mind) and the widely held belief that aquifers represent a pristine source of drinking water due to natural attenuation may represent the "perfect storm" causing direct consumption of relatively large volumes of surface flood-contaminated groundwater. Accordingly, the current study sought to systematically identify and synthesize all available peer-reviewed literature pertaining to the nexus between surface flooding, groundwater contamination and human gastroenteric outcomes. Just 14 relevant studies were found to have been published during the period 1980-2017, thus highlighting the fact that this potentially significant source of climate-related exposure to environmental infection has remained understudied to date. Studies differed significantly in terms of type and data reporting procedures, making it difficult to discern clear trends and patterns. Approximately 945 confirmed cases of flood-related enteric disease were examined across studies; these concurred with almost 10,000 suspected cases, equating to approximately 20 suspected cases per confirmed case. As such, no regional, national or global estimates are available for the human gastrointestinal health burden of flood-related groundwater contamination. In light of the demonstrable public health significance of the concurrent impacts of groundwater susceptibility and climate change exacerbation, strategies to increase awareness about potential sources of contamination and motivate precautionary behaviour (e.g. drinking water testing and treatment, supply interruptions) are necessary. Mainstreaming climate adaptation concerns into planning policies will also be necessary to reduce human exposure to waterborne sources of enteric infection.

International audience; The Critical Raw Material (CRM) Deposit Map of Europe, prepared by EuroGeoSurvey's Mineral Resources Expert Group (MREG), shows European mineral deposits from the ProMine Mineral Deposit database containing critical commodities, according to the 2014 list of critical raw materials of the European Commission. EuroGeoSurveys (EGS), The Geological Surveys of Europe, is a not-for-profit organization representing 37 National Geological Surveys and some regional Geological Surveys in Europe. It provides the European Institutions with expert, independent, balanced and practical pan-European advice and information as an aid to problem-solving, policy development, regulatory and programme formulation in areas such as natural resources, energy and geo-hazards. The EGS MREG is actively involved in contributing to policy and strategy-making processes aimed at identifying, characterizing and safeguarding resource potential, especially for critical raw materials through data provision, research, technological development and innovation. The European Union aspires to reducing the import dependency of raw materials, especially CRM, that are essential to Europe's industries. In this respect, mineral resource information, data sharing and networking by European Geological Surveys is crucial. The Strategic Implementation Plan of the European Innovation Partnership on Raw Materials highlights the need for establishing and maintaining a common interoperable EU Geological Knowledge Base. Such a Knowledge Base will support exploration for indigenous mineral resources and strengthen policy and decision making. In 2010, the European Commission identified 14 non energy non-agricultural raw materials as being critical. Criticality is based on both the scarcity of supply and the importance to European industry. This list was updated in 2014 to include 7 new commodities with one being dropped from the original list. The list now comprises: antimony, beryllium, borates, chromium, cobalt, coking coal, fluorspar, gallium, germanium, graphite, indium, magnesite, magnesium, niobium, phosphate rock, platinum group metals, light and heavy rare earth elements (separately), silicon metal and tungsten. ProMine was a European Union (EU) co-funded project, which had as its main objective the stimulation of the extractive industry to deliver new products to manufacturing industry. A major deliverable of the project was the ProMine Mineral Deposit (MD) database that contains information related to almost 13,000 mineral deposits in Europe. In order to extract data to be displayed on the CRM map of Europe, the ProMine MD database was queried for all commodities on the EC CRM list which were in the medium to super-large deposit size. Following this, the dataset was circulated to MREG in order to verify, validate and update the list.