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We exploit the data from five seismic transects deployed across the Pyrenees to characterize the deep architecture of this collisional orogen. We map the main seismic interfaces beneath each transect by depth migration of P-to-S converted phases. The migrated sections, combined with the results of recent tomographic studies and with maps of Bouguer and isostatic anomalies, provide a coherent crustal-scale picture of the belt. In the Western Pyrenees, beneath the North Pyrenean Zone, a continuous band of high density/velocity material is found at a very shallow level (~10 km) beneath the Mauleon basin and near Saint-Gaudens. In the Western Pyrenees, we also find evidence for northward continental subduction of Iberian crust, down to 50–70 km depth. In the Eastern Pyrenees, these main structural features are not observed. The boundary between these two domains is near longitude 1.3 °E, where geological field studies document a major change in the structure of the Cretaceous rift system, and possibly a shift of its polarity, suggesting that the deep orogenic architecture of the Pyrenees is largely controlled by structural inheritance. The PYROPE (Pyrenean Observational Portable Experiment) project was supported by the Agence Nationale de la Recherche (ANR) Blanc Programme (project PYROPE, ANR-09- BLAN-0229). We also acknowledge SISMOB, the French seismic mobile pool (a component of the RESIF consortium - http://seismology.resif.fr), for providing us with the seismological instrumentation for the temporary deployments. Field work has been also partially funded by the Spanish Ministry of Economy and Competitiveness through Project MISTERIOS (CGL2013-48601-C2-2-R). Peer reviewed

© 2018 American Chemical Society. Halterman corroles have been synthesized for the first time from pyrrole and Halterman's aldehyde via Gryko's "water-methanol method". These were derivatized to the corresponding copper complexes and subsequently to the β-octabromo complexes. Electronic circular dichroism spectra were recorded for the enantiopure copper complexes, affording the first such measurements for the inherently chiral Cu corrole chromophore. Interestingly, for a given configuration of the Halterman substituents, X-ray crystallographic studies revealed both P and M conformations of the Cu-corrole core, proving that the substituents, even in conjunction with β-octabromination, are unable to lock the Cu-corrole core into a given chirality. The overall body of evidence strongly indicates a dynamic equilibrium between the P and M conformations. Such an interconversion, which presumably proceeds via saddling inversion, provides a rationale for our failure so far to resolve sterically hindered Cu corroles into their constituent enantiomers by means of chiral HPLC.

AbstractThe ability to predict the magnitude of an earthquake caused by deep fluid injections is an important factor for assessing the safety of the reservoir storage and the seismic hazard. Here, we propose a new approach to evaluate the seismic energy released during fluid injection by integrating injection parameters, induced aseismic deformation, and the distance of earthquake sources from injection. We use data from ten injection experiments performed at a decameter scale into fault zones in limestone and shale formations. We observe that the seismic energy and the hydraulic energy similarly depend on the injected fluid volume (V), as they both scale as V3/2. They show, however, a large discrepancy, partly related to a large aseismic deformation. Therefore, to accurately predict the released seismic energy, aseismic deformation should be considered in the budget through the residual deformation measured at the injection. Alternatively, the minimal hypocentral distance from injection points and the critical fluid pressure for fault reactivation can be used for a better prediction of the seismic moment in the total compilation of earthquakes observed during these experiments. Complementary to the prediction based only on the injected fluid volume, our approach opens the possibility of using alternative monitoring parameters to improve traffic-light protocols for induced earthquakes and the regulation of operational injection activities.

International audience; In the framework of EPOS (EPOS - European Plate Observing System) project implementation phase, an analysis center is hosted in France at Université Grenoble Alpes – CNRS.Within the work package WP10, GNSS data and product, UGA-CNRS is responsible for providing products (position time series and velocity field) generated by a processing using double difference method (via GAMIT/GLOBK software). For this purpose, we developed strategies to take up the up-scaling challenge and generate from a big data set the usual GNSS products. For computational efficiency, the massive data set was split into sub-networks and the GAMIT software launched for each sub-network independently, following the same approach than the one presented in the framework of the PBO project.The informatics resources at our disposal are composed of a management tool for batch processing on computing environments (CiGri) and an open source data management software (IRODS), installed on the high performance computer available at UGA (CIMENT). Concerning the velocity field computation, we used MIDAS software. A few different tests were performed in order to check the reliability of our solution and to determine the best way to proceed.We also take advantage of the human and computational resources available in order to include in our solution some no-EPOS stations and generate:- An exhaustive solution in France, including stations from Rénag, RGP and Orpheon. Such dense solution was never performed before using DD method. - A solution in Greece including data from the SMARTNET network.Our solution includes more than 1500 stations constituting a widespread pan-European network, over an 18-years time span [2000-2017].; Dans le cadre de la phase de mise en œuvre du projet EPOS (EPOS - European Plate Observing System), un centre d'analyse est hébergé en France à l'Université Grenoble Alpes - CNRS.Dans le cadre du work package WP10, données GNSS et produit, UGA-CNRS est responsable de la fourniture des produits (séries temporelles de position et champ de vitesse) générés par un traitement utilisant la méthode des doubles différences (via le logiciel GAMIT/GLOBK). Pour ce faire, nous avons développé des stratégies pour relever le défi de la mise à l'échelle et générer à partir d'un grand ensemble de données les produits GNSS habituels. Par souci d'efficacité informatique, l'énorme ensemble de données a été divisé en sous-réseaux et le logiciel GAMIT a été lancé indépendamment pour chaque sous-réseau, suivant la même approche que celle présentée dans le cadre du projet PBO.Les moyens informatiques à notre disposition sont composés d'un outil de gestion des traitements batch sur environnements informatiques (CiGri) et d'un logiciel de gestion de données open source (IRODS), installés sur l'ordinateur haute performance disponible chez UGA (CIMENT). En ce qui concerne le calcul du champ de vitesse, nous avons utilisé le logiciel MIDAS. Quelques tests différents ont été effectués afin de vérifier la fiabilité de notre solution et de déterminer la meilleure façon de procéder.Nous profitons également des ressources humaines et informatiques disponibles afin d'inclure dans notre solution des stations sans EPOS et de générer :- Une solution exhaustive en France, incluant les stations de Rénag, RGP et Orphéon. Une telle solution dense n'a jamais été réalisée avant l'utilisation de la méthode DD. - Une solution en Grèce incluant les données du réseau SMARTNET.Notre solution comprend plus de 1500 stations constituant un réseau paneuropéen étendu, sur une période de 18 ans (2000-2017).

International audience; The availability of GPS survey data spanning 22 years, along with several independent velocity solutions including up to 16 years of permanent GPS data, presents a unique opportunity to search for persistent (and thus reliable) deformation patterns in the Western Alps, which in turn allow a reinterpretation of the active tectonics of this region. While GPS velocities are still too uncertain to be interpreted on an individual basis, the analysis of range-perpendicular GPS velocity profiles clearly highlights zones of extension in the center of the belt (15.3 to 3.1 nanostrain/year from north to south), with shortening in the forelands. The contrasting geodetic deformation pattern is coherent with earthquake focal mechanisms and related strain/stress patterns over the entire Western Alps. The GPS results finally provide a reliable and robust quantification of the regional strain rates. The observed vertical motions of 2.0 to 0.5 mm/year of uplift from north to south in the core of the Western Alps is interpreted to result from buoyancy forces related to postglacial rebound, erosional unloading, and/or viscosity anomalies in the crustal and lithospheric root. Spatial decorrelation between vertical and horizontal (seismicity related) deformation calls for a combination of processes to explain the complex present-day dynamics of the Western Alps.

AbstractMining, water-reservoir impoundment, underground gas storage, geothermal energy exploitation and hydrocarbon extraction have the potential to cause rock deformation and earthquakes, which may be hazardous for people, infrastructure and the environment. Restricted access to data constitutes a barrier to assessing and mitigating the associated hazards. Thematic Core Service Anthropogenic Hazards (TCS AH) of the European Plate Observing System (EPOS) provides a novel e-research infrastructure. The core of this infrastructure, the IS-EPOS Platform (tcs.ah-epos.eu) connected to international data storage nodes offers open access to large grouped datasets (here termed episodes), comprising geoscientific and associated data from industrial activity along with a large set of embedded applications for their efficient data processing, analysis and visualization. The novel team-working features of the IS-EPOS Platform facilitate collaborative and interdisciplinary scientific research, public understanding of science, citizen science applications, knowledge dissemination, data-informed policy-making and the teaching of anthropogenic hazards related to georesource exploitation. TCS AH is one of 10 thematic core services forming EPOS, a solid earth science European Research Infrastructure Consortium (ERIC) (www.epos-ip.org).

We present a general concept for evolutionary, collaborative, multiscale inversion of geophysical data, specifically applied to the construction of a first-generation Collaborative Seismic Earth Model. This is intended to address the limited resources of individual researchers and the often limited use of previously accumulated knowledge. Model evolution rests on a Bayesian updating scheme, simplified into a deterministic method that honors today's computational restrictions. The scheme is able to harness distributed human and computing power. It furthermore handles conflicting updates, as well as variable parameterizations of different model refinements or different inversion techniques. The first-generation Collaborative Seismic Earth Model comprises 12 refinements from full seismic waveform inversion, ranging from regional crustal- to continental-scale models. A global full-waveform inversion ensures that regional refinements translate into whole-Earth structure. ©2018. American Geophysical Union. All Rights Reserved. This work was supported by the PASC project GeoScale, the CSCS computing time grant ch1, the European Research Council (ERC) under the EU’s Horizon 2020 programme (grant 714069), Istanbul Technical University, the National Science Council of Turkey, the A. v. Humboldt Foundation, and the EU-COST Action ES1401-TIDES-STSM. Andreas Fichtner et. al. Peer reviewed

International audience; In the framework of the implementation phase of the European Plate Observing System (EPOS) project, a pan-European processing center is hosted in Université Grenoble Alpes – CNRS, France. The prototype solution spans the 2005-2015 period, and includes more than 500 European cGPS stations. RInEx data and metadata from RING, NOA and Rénag cGPS networks were downloaded from archive centres (GSAC) maintained in France (CNRS-OCA), Greece (NOA) and Italy (INGV). RINEX data from the European Permanent Network (EPN) were downloaded from the EPN ftp server. Data were processed in double difference with the GAMIT/GLOBK software. The network is first split into daily sub-networks (between 8 and 14 sub-networks) using NETSEL tool included in the GAMIT/GLOBK package. The sub-networks consist in about 40 stations, with 2 overlapping stations. For each day and for each sub-network, the GAMIT processing is conducted independently on the high performance computing platform CIMENT hosted at the University of Grenoble Alpes (UGA). A quality check on GAMIT post-fit RMS allows then to identify potential errors, correct them and launch again the processing. Once each sub-network achieves satisfactory results, a daily combination is performed in order to produce SINEX files. The Chi square value associated with the combination allows us to evaluate its quality. This quality check pointed out some necessary sub-networks reorganisation concerning only a few days. Eventually, a multi year combination generates position time series for each station. Each time series is visualized and the jumps associated with material change (antenna or receiver) are estimated and corrected. This procedure allows us to generate daily solutions, position time series and velocity field to be distributed as Level-1 or level-2 EPOS-GNSS products.; Dans le cadre de la phase de mise en œuvre du projet EPOS (European Plate Observing System), un centre de traitement paneuropéen est hébergé à l'Université Grenoble Alpes - CNRS, France. La solution prototype couvre la période 2005-2015 et comprend plus de 500 stations cGPS européennes. Les données et métadonnées RInEx des réseaux RING, NOA et Rénag cGPS ont été téléchargées depuis les centres d'archives (GSAC) maintenus en France (CNRS-OCA), Grèce (NOA) et Italie (INGV). Les données RINEX du Réseau permanent européen (EPN) ont été téléchargées depuis le serveur ftp de l'EPN. Les données ont été traitées en double différence avec le logiciel GAMIT/GLOBK. Le réseau est d'abord divisé en sous-réseaux quotidiens (entre 8 et 14 sous-réseaux) à l'aide de l'outil NETSEL inclus dans le package GAMIT/GLOBK. Les sous-réseaux se composent d'une quarantaine de stations, dont deux se chevauchent. Pour chaque jour et pour chaque sous-réseau, le traitement GAMIT est réalisé indépendamment sur la plate-forme de calcul haute performance CIMENT hébergée à l'Université de Grenoble Alpes (UGA). Un contrôle de qualité sur GAMIT post-fit RMS permet alors d'identifier les erreurs potentielles, de les corriger et de relancer le traitement. Une fois que chaque sous-réseau obtient des résultats satisfaisants, une combinaison quotidienne est effectuée afin de produire des fichiers SINEX. La valeur du chi carré associée à la combinaison nous permet d'évaluer sa qualité. Ce contrôle de qualité a mis en évidence quelques réorganisations de sous-réseaux nécessaires pour quelques jours seulement. Finalement, une combinaison pluriannuelle génère des séries chronologiques de positions pour chaque station. Chaque série temporelle est visualisée et les sauts associés au changement de matériau (antenne ou récepteur) sont estimés et corrigés. Cette procédure nous permet de générer des solutions quotidiennes, des séries chronologiques de position et des champs de vitesse qui seront distribués sous forme de produits EPOS-GNSS de niveau 1 ou 2.

La construction du réseau sismologique et géodésique français Résif a été lancée en 2009 pour fédérer, moderniser et développer les moyens d’observation géophysique de la Terre interne. Cette infrastructure de recherche nationale est aujourd'hui intégrée à l'infrastructure européenne EPOS et participe activement à sa réalisation et à son évolution. Par ailleurs, certaines composantes de Résif-Epos font partie de structures fédératives à l’échelle mondiale.Résif-Epos se base à la fois sur des réseaux permanents et sur des parcs d’instruments mobiles pour effectuer des mesures sismologiques, géodésiques et gravimétriques continues. Les données recueillies révèlent la structure et les déformations de notre planète. Elles contribuent également à la gestion durable des ressources naturelles et à la maîtrise des risques naturels d’origine tellurique.En sismologie, Résif-Epos développe un réseau permanent et dense de près de 200 capteurs à large bande passante sur l’ensemble du territoire métropolitain. Pour le compléter, le réseau accélérométrique permanent dispose de capteurs plutôt dédiés à l’étude des mouvements forts et localisés dans les zones les plus sismiques en métropole et Outre-Mer.Ces réseaux permettent aux chercheurs de mieux connaître et d'imager l'intérieur de la Terre depuis la croûte jusqu’au noyau terrestre. Outils de base pour le suivi en temps réel de l’activité sismique, ils aident également à estimer l'aléa sismique, c’est-à-dire la probabilité qu'une secousse dépasse un certain seuil en un lieu et sur une durée donnés.Résif-Epos intègre également un réseau permanent de stations géodésiques. Capables de mesurer des vitesses de déplacement du sol de l’ordre de quelques dixièmes de millimètres par an, elles permettent de suivre les déformations de l’écorce terrestre et les processus à l’origine des reliefs et de la sismicité, notamment au niveau des failles.Résif-Epos dispose par ailleurs de gravimètres qui mesurent les variations infimes du champ de pesanteur et permettent d’étudier la répartition et la dynamique des masses à l’intérieur de la Terre.En complément de ces réseaux permanents, Résif-Epos coordonne différents parcs d’instruments mobiles qui permettent de densifier temporairement les mesures en France ou dans des zones à fort intérêt scientifique en Europe ou dans le Monde. Ouverts à toute la communauté scientifique académique, ils proposent des équipements variés, modernes et parfois exceptionnels, comme un gravimètre absolu basé sur la chute d’atomes froids. Un système d'information performant gère la dizaine de téraoctets de données collectée annuellement. Les données brutes sont analysées, validées puis centralisées afin d’être sauvegardées et mises à disposition en temps réel et gratuitement, suivant une politique de science ouverte. Chaque année, des dizaines de millions de requêtes sont effectuées sur les serveurs par des scientifiques du monde entier.L'Institut National des Sciences de l'Univers du CNRS coordonne le consortium Résif-Epos, composé de la majorité des universités et organismes français concernés par la recherche en Géosciences. Plus d'une centaine de chercheurs, ingénieurs et techniciens collaborent au quotidien pour faire de Résif-Epos un formidable outil scientifique au service de la communauté mondiale des sciences de la Terre.

The Near Fault Observatories (NFOs) community is one of the European Plate Observing System (EPOS, http://www.epos-eu.org) Thematic Communities, today consisting of six research infrastructures that operate in regions characterised by high seismic hazard originating from different tectonic regimes. Earthquakes respond to complex natural systems whose mechanical properties evolve over time. Thus, in order to understand the multi-scale, physical/chemical processes responsible for the faulting that earthquakes occur on, it is required to consider phenomena that intersect different research fields, i.e., to put in place multidisciplinary monitoring. Hence, NFOs are grounded on modern and multidisciplinary infrastructures, collecting near fault high resolution raw data that allows generation of innovative scientific products. The NFOs usually complement regional backbone networks with a higher density distribution of seismic, geodetic, geochemical and other geophysical sensors, at surface and sometimes below grade. These dense and modern networks of multi-parametric sensors are sited at and around active faults, where moderate to large earthquakes have occurred in the past and are expected in the future. They continuously monitor the underlying Earth instability processes over a broad time interval. Data collected at each NFO results in an exceptionally high degree of knowledge of the geometry and parameters characterizing the local geological faults and their deformation pattern. The novel data produced by the NFO community is aggregated in EPOS and is made available to a diverse set of stake-holders through the NFO Federated Specific Data Gateway (FRIDGE). In the broader domain of the Solid Earth sciences, NFOs meet the growing expectations of the learning and communication sectors by hosting a large variety of scientific information about earthquakes as a natural phenomenon and a societal issue. It represents the EPOS concept and objective of aggregating and harmonising the European research infrastructures capabilities to facilitate broader scientific opportunity. The NFOs are at the cutting edge of network monitoring. They conduct multidisciplinary experiments for testing multi-sensor stations, as well as realise robust and ultra-low latency, transmis-sion systems that can routinely accommodate temporary monitoring densification. The effort to continuously upgrade the technological efficiency of monitoring systems positions the NFO at the centre of marketing opportunities for the European enterprises devoted to new sensor technology. The NFOs constitute ideal test beds for generating expertise on data integration, creating tools for the next generation of multidisciplinary research, routine data analysis and data visualization. In particular focus is often on near-real time tools and triggering alarms at different levels are tested and implemented, strengthening the cooperation with the Agencies for risk management. NFOs have developed innovative operational actions such as the Testing Centre for Earthquake Early Warning and Source Characterisation (CREW) and detailed fast ground shaking and damage characterization. Complementing the recent growth of modern laboratory and computational models, the NFOs can provide interdisciplinary observations of comparable high resolution to describe the behaviour of fault slip over a vast range of spatial and temporal scales and aiding to provide more accurate earthquake hazard characterizations. Annals of Geophysics, 65 (3) ISSN:1593-5213