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This data publication contains the compilation of global heat-flow data by the International Heat Flow Commission (IHFC; http://www.ihfc-iugg.org/) of the International Association of Seismology and Physics of the Earth's Interior (IASPEI). The presented data release 2021 contains data generated between 1939 and 2021 and constitutes an updated and extended version of the 2012 IHFC database release (IHFC 2012; later re-published as PANGAEA release: Global Heat Flow Compilation Group, 2013). The 2021 release contains 74,548 heat-flow data from 1,403 publications. 55% of the reported heat-flow values are from the continental domain (n ~ 40,870), while the remaining 45% are located in the oceanic domain (n ~ 33,678). The data are provided in csv and Excel formats. Compared to earlier compilations, which followed the structure defined by Jessop et al. (1976), the new data release was transformed to the recently redefined structure for reporting and storing heat-flow data in the Global Heat Flow Database (Fuchs et al., 2021). Therefore, the notation and structure of the database was adopted, transforming the database field entries defined after Jessop et al. (1976) to the new field structure. Old code notations are not continued and the dataset was cleaned for entries without reporting any heat-flow value. Although successfully transformed, this release marks an intermediate step as the majority of the newly defined database fields have not been filled yet. Filling these fields, checking the existing entries and assessing the quality of each entry are the aim of the upcoming Global Heat Flow Data Assessment Project, for which this data set provides the basis. Consequently, we kindly ask the user to take notice that the current release still suffers similar problems as previously published compilations in terms of data heterogeneity, documentation and quality.

International audience; In order to understand the unprecedented underwater telluric event of the Mayotte Seismo-Volcanic (MSV) crisis (2018-2020), it appears essential to reach a critical level of knowledge on the evolution of the seismicity, volcanic activity and geodetic deformation, but also on the geodynamic context. This includes the kinematics and the characterization of the lithospheric and crustal structures, on both short- and long-term and regional and local scales. Towards this goal, the COYOTES project aims to better understand the regional geodynamic and geological context of the northern Mozambique Channel. The objectives are to understand the distribution of active and recent deformations around the Comoros Archipelago, in particular the Mayotte Island, to image the crustal structuration and to study the recent tectono-sedimentary evolution. Both the link with the East African rift system and the role of Mesozoic inherited structures in the spatial distribution of present-day deformation associated to the MSV crisis will be investigated. This updated geodynamic and geological knowledge will be used to improve the assessment of the volcanic and seismic hazards of the Comoros archipelago and especially around Mayotte. The main work-packages are 1) Current seismic sequence, deformation and kinematics; 2) Recent and active volcanism and tectonics in the Comoros archipelago; 3) Long-term geodynamics: Regional structuration and inheritance. It will integrate new onshore and offshore acquisitions of geological and geophysical data, their interpretation as well as modelling.The COYOTES project (http://www.geocean.net/coyotes/doku.php?id=start) is funded by the ANR (French Agence Nationale de la Recherche) for the period 2020-2024, involving three thesis, one post-doc and more than 30 scientists from the BRGM, IPGS/EOST, IPGP, IsTep, ENS, La Réunion University, EPOC, Ifremer, SHOM, GEOPS, LMV, GET, ISTO, OVPF, .... The project is linked with the SISMAORE oceanographic campaign that will occur on the R/V Pourquoi Pas? from December 2020 to February 2021.

Workshop. Alboran Domain and Gibraltar Arc: Geological Research and Natural Hazards - El dominio de Alborán y el Arco de Gibraltar: Investigación geológica y riesgos naturales - Le Domaine Alboran et l'Arch de Gibraltar: Recherche géologique et risques naturels, 16-18 octubre 2019, Granada..-- 2 pages, In converging plate boundaries, upper-plate extension can occur in a limited amount of space and time according to plate kinematics and to lower plate behaviour. It is considered to be the result of slab roll-back and can be associated to a segmentation of the downgoing slab with the development of sub-vertical lithospheric-scale tear faults on its edges. The development of the slab tear triggers formation of STEP faults (Subduction Tear Edge Propagator). These STEP faults, that bound laterally the back-arc basins, accommodate the progressive tear of the slab and its lateral motion. The transition from back arc extension to inversion leads to a complex structural setting. The thinned continental crust of the Alboran Sea and its overlying sedimentary cover are deformed since the Miocene by both convergence between Eurasia and Africa and deep processes related to the Tethyan slab retreat. Part of the deformation is recorded in the southern Alboran Sea through the Xauen and Tofiño banks (named the South Alboran Ridge or SAR) where oceanographic surveys acquired swath bathymetry and seismic reflection. Major questions concerning the setting up of these structures and the present-day deformation remain still open: (i) what was the initial geometry of the southern margin of the west Alboran Basin? (ii) How and where is accommodated the shortening related to the Africa-Eurasia convergence? (iii) What is the role of weak Miocene undercompacted shales and muds on the structural style of the Banks (Comas, Platt, et al., 1999)?. Four main stages of deformation have been recognized in the SAR region. Early-Miocene extension occurs with syn-tectonic wedges related to normal faulting, as already observed in the North Alboran Ridge. The SAR region is interpreted as the continuity of the very thick Miocene West Alboran depocenter related to the west Alboran mud province. Linked to the Gibraltar slab retreat, we suggest that the southern part of the WAB depocenter was deformed by the activity of a STEP fault, which is subsequently inverted. We then interpret the SAR zone to have formed by contractional overprinting of a shear zone. The present-day SAR region is dominated by E-W trending folds and thrusts with evidence of compressional deformation active from late Miocene to presentday. An acceleration in the uplift and compressional activity is evidenced during the top Miocene. The structural style of the fold and thrust suggests a weak decollement layer corresponding to the overpressure shale, but can also reflect the existence of an intracrustal fault. The Tortonian inversion and associated gravity-driven movement, superimposed with the Africa indentation, induced the present-day style of deformation of the SAR. Our study allows to understand which tectonic and sedimentary processes are responsible of the final structure observed through the South Alboran basin. We show that weak layers and inherited crustal structures play a major role on the style and mode of deformation of the back-arc basin. In particular, the major tectonic imprint of the STEP faults, accommodating slab-roll back, as well as the sedimentary imprint of the undercompacted shale acting as a decollement layer, are highlighted. Understanding deformation processes around the tip of back-arc basins will provide key information on the forces and dynamics controlling the inversion of STEP faults on the edge of subduction areas. Wide-angle seismic studies are necessary to elucidate the presence and geometry of the deep crustal structure as the STEP fault and intra-crustal thrusts

Prioritaire 1 - voir rapport d'évaluation (https://www.flotteoceanographique.fr/content/download/29325/199063/file/CR-CNFH-novembre-2016-V12.pdf); La campagne SEAGAL est demandée sur la marge nilotique à bord du NO Marion Dufresne par l’UMR Géoazur en collaboration avec des partenaires français (Universités de Nice Sophia Antipolis, UPMC et Université Bordeaux1, Ifremer), Brésiliens (PUCRS-IPR), Allemands (Jacobs University Bremen), Italiens (OGS) et Egyptiens (Université d’Alexandrie). Elle est basée sur des résultats/hypothèses touchant aux interactions entre les glissements sous-marins à grande échelle et la circulation/échappement de fluides et gaz, dans le contexte de l'évolution de la stabilité des hydrates de gaz au cours des cycles climatiques glaciaires-interglaciaires. SEAGAL propose une étude pluridisciplinaire (géophysique, géologique, géochimique, géotechnique et géothermique) de zones d’intérêt de la Province Centrale du delta profond du Nil afin de :(1) Etudier la nature et l'origine des structures de cheminées gazeuses qui sont enracinées dans la zone de stabilité d’hydrates de gaz (GHSZ) et qui émettent du gaz vers les océans par le biais de pockmarks. En particuliers, il s’agira de tester les modèles proposés pour ces cheminées qui se formeraient soit par la remontée de fluides salés et tièdes et provoqueraient l’amincissement de la zone de stabilité des hydrates, soit par l’expulsion rapide du sel contenu dans les eaux interstitielles par un flux rapide de gaz et qui permettrait la formation d’hydrates. Ceci sera abordé par le prélèvement de longues carottes Calypso, de mesures Penfeld et de flux de chaleur le long de transects recoupant des pockmarks afin de caractériser la composition des fluides interstitiels, les flux verticaux et horizontaux de fluides en relation avec la distribution des hydrates de gaz. Cette approche permettra de tester les modèles existants de fonctionnement des conduits issus de la zone de stabilité des hydrates de gaz et de proposer éventuellement un modèle alternatif, applicable à d’autres zones géographiques.(2) Comprendre l’impact des circulations de fluides associées aux pockmarks sur la couverture sédimentaire superficielle et son fluage progressif. Il s’agira de quantifier l’état de stabilité de la pente continentale et de mieux contraindre l’interaction fluides-sédiments sur le déclenchement des instabilités sédimentaires en associant pour la première fois sur cette marge l’acquisition de données Penfeld et de carottes longues pour analyser le comportement rhéologique des matériaux dans les zones affectées par les fluides et la déformation et dans les zones non affectées.(3) Tester l’hypothèse selon laquelle la dissociation des hydrates de gaz serait responsable des glissements géants (10-1000 km3) sur les marges continentales, en particulier la série de MTDs identifiés à la limite entre les Provinces centrale et occidentale de la marge nilotique au cours des derniers 115 kyrs. La marge nilotique est en effet l’une des zones les plus favorables au monde pour contraindre l’impact de la dissociation des hydrates de gaz sur le déclenchement de glissements, car la Méditerranée a connu des augmentations de la température des eaux de fond qui ont dû réduire le domaine de stabilité des hydrates de gaz à l’échelle de bassin, provoquant alors une augmentation des pressions interstitielles sur de grandes zones. L’un des objectifs de SEAGAL est donc d’obtenir pour la première fois sur la marge nilotique une estimation des variations de la température des eaux de fond à partir d’analyses Ca/Mg réalisées sur des foraminifères benthiques afin de pouvoir modéliser les changements induits sur la zone de stabilité des hydrates au cours des derniers 115 kyrs et comparer les périodes de dissociation des hydrates avec les âges des MTDs.La demande de campagne SEAGAL s’appuie sur l’expérience des équipes scientifiques françaises en Méditerranée orientale, acquise depuis 1998 dans le cadre de programmes nationaux et européens. SEAGAL s’appuie sur le projet européen SEAGAS (2016-2019), une collaboration franco-brésilienne étudiant la dynamique des hydrates de gaz sur les marges du Nil et de l’Amazone.; The SEAGAL campaign of the RV Marion Dufresne to the Nile deep-sea fan is proposed by UMR Geoazur in collaboration with partners from France (Universities of Nice Sophia Antipolis, UPMC and Bordeaux1, Ifremer), Brazil (IPR-PUCRS), Germany (Jacobs University Bremen), Italy (OGS) and Egypt (University of Alexandria). The campaign proposal builds on previous investigations of the interactions of large-scale sediment failure with fluid flow and gas venting, in the context of changing gas hydrate stability during glacial-interglacial cycles of climate. SEAGAL proposes a multidisciplinary study (geophysical, geological, geochemical geotechnical and geothermal) of targets in the central province of the Nile fan, to address three main objectives:(1) To investigate the nature and origin of chimney-like structures within the gas hydrate stability zone (GHSZ) that are venting gas to the oceans through seabed pockmarks, in particular to test proposed models in which they form by the rise of hot and/or saline fluids to thin the GHSZ, versus a mechanism of salt exclusion that links the basal phase boundary to seabed. This will be achieved through the acquisition along transects across selected features of measurements up to 40 m below seabed, including Calypso cores, penetrometer data and geothermal measurements, in order to identify composition of pore fluids and gases, and to characterise vertical and horizontal fluxes of fluids and heat in relation to the distribution of gas hydrates and carbonates. The results will be applied to modelling of gas hydrate stability to test proposed models for chimney formation, or to propose a new model. We will also acquire multibeam water column data to examine spatial and temporal variations in gas flux from pockmarks on the central Nile fan since the 2011 APINIL campaign.(2) To examine the relation of fluid circulation to processes of downslope creep of the sediment cover above buried mass transport deposits (MTDs). This will be achieved by the first ever acquisition of transects of penetrometer data and Calypso cores up to 40 m long from wave-like deformation features and subjacent MTDs, in order to characterise the mechanical properties of sediments and bounding faults in relation to the distribution of carbonates and flux of fluids. The results will be used as original input to geotechnical modelling of mass failure and post-failure processes, in order to constrain the triggering factors of failure and their potential consequences (e.g. tsunamis).(3) To test the relation between gas hydrate stability changes and large submarine landslides, in particular to a series of MTDs on the western edge of the central Nile province dated to the last 115 ka. The Nile fan is one of the best places in the world to test the hypothesis that gas hydrate dissociation can trigger sediment failures, due to basin-wide changes in Mediterranean bottom water temperatures (bwts) of up to 4 ̊ C that drove large changes in the GHSZ at all water depths below c. 1000 m. This will be done using Mg/ Ca paleotemperature data from benthic foraminifera in sediment cores to reconstruct the history of bwt changes, as input to modelling of GHSZ changes in response to both temperature and sea level variations over last 115 ka, allowing accurate comparison of periods of gas hydrate dissociation to the ages of 11 giant MTDs.The SEAGAL proposal builds on French-led international investigations of the eastern Mediterranean Sea since 1998, undertaken in the context of national and European projects. SEAGAL is linked to the EC-funded project SEAGAS (2016-2019), a French-Brazilian collaboration coordinated by Géoazur to investigate gashydrate dynamics on the Mediterranean and Brazilian margins, inspired by the 2011 APINIL campaign and intended to lead to future trans-Atlantic research projects.

Poort, Jeffrey ... et al.-- COST-ANR MEDSALT Symposium, 24-28 October 2016, Palermo, Italy.-- 2 pages, While there is now a large consensus that Western Mediterranean basins developed in a Miocene back-arc setting due to slab roll-back and that some of its domains are floored by oceanic crust, there is still a lot of speculation on the configuration, nature and evolution of its margins and the ocean-continent transitions (OCT). A thick Messinian layer of evaporites in the deep basin obscures deep seismic reflectors, and only recently seismic refraction and wide-angle studies revealed a confident picture of basement configuration. In order to further constrain models of crustal structure and margin evolution, heat flow is one of the key parameters needed. Recent heat flow studies on other margins have shown the existence of a persistent thermal anomaly under rifted margins that urges to reconsider the classical models of its evolution. The young age of OCT and ceased oceanic formation in the Western Mediterranean make it an interesting test case for a thermo-mechanical study of its margins. The presence of halokinetic structuring and salt diapirs urges the need of close spaced heat flow measurement to evaluate heat refraction and advective heat transfer by fluid migration. During the WestMedFlux cruise on the research vessel L'Atalante in April/May this year we collected a total of 150 new heat flow measurement (123 in pogo mode, 27 with a sediment corer) in the deep basin of the Western Mediterranean where heat flow data were sparse. These data are aligned along several regional heat flow profiles crossing the OCTs of the Provencal basin and the Algero-Balearic basins, covering conjugated margins, divergent and oblique margins, transform faults and oceanic crust of different ages. Closely spaced measurements have been realized in several salt diapir and submarine mount areas. At 20 of the coring stations, pore water fluids have been extracted on board using rhizon sampling and gas was extracted using the head space method, while core description has been realized on board for 15 of the cores. Sub-bottom profiling, multi-beam data and ADCP have been collected along most of the cruise track, with water column multi-beam mode for a few selected areas. Preliminary analysis of the heat flow data indicate the absence of a strong regional contrast between continental and oceanic domain, but shows the presence of important local heat flow anomalies, in particular on the south Balearic margin (a variation from 20 to 150 mWm² over a distance of only a few kilometers). Some of these thermal anomalies coincide with salt diapiric structures, others are located in the margin slope near the marginal fault systems. Further processing and pore water and gas analysis will help defining the source of these thermal anomalies, and to test if sub-salt fluid migration and post-Messinian salt deformation play a role in the creation of these anomalous surface heat flow patterns

Poort, Jeffrey ... et. al.-- AAPG European Regional Conference & Exhibition. Exploring The Mediterranean: New Concepts In An Ancient Seaway, 8-10 April 2013, Barcelona, Spain

Since the Tortonian, the thinned continental crust and the overlying sedimentary cover of the Alboran Sea are submitted to tectonic inversion due to the convergence between Eurasia and Africa. The past and present deformation is significant along the Moroccan margin where the MARLBORO-1 cruise in 2011, acquired 1100 km of mid-resolution seismic reflection along 20 profiles perpendicular and parallel to the margin, off Al Hoceima, to latitude 36°N. The study area located on the Xauen/Tofino banks and the South Alboran ridge off Morocco, shows signs of both past and present strong tectonic deformation, submarine landslides, and contourites, EGU General Assembly 2012, Vienna, 22-27 April