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The Mauléon Basin, in the northwestern Pyrenean Belt, is related to Early Cretaceous rifting and mantle denudation. Here we review the evolution of depositional systems in the Mauléon Rift Basin during Albian and Cenomanian time. This review includes the lithostratigraphy, regional distribution, boundaries, age and facies sedimentology of the basin’s syn-rift formations and their members. We construct paleogeographic maps to elucidate (1) the 3D distribution of sedimentary facies and depositional systems during the Albian and Cenomanian from the Iberian proximal margin to the hyperextended domain and (2) the link between major extensional structures and sedimentation during rifting and mantle denudation. The Mauléon Rift was supplied during most of the Albian by sediments from the Iberian proximal margin. The southern margin had a steep and abrupt topographic boundary related to a northward crustal rollover along the south-dipping Saint-Palais detachment. This feature controlled the deposition of coarse-grained turbidites at the base of the margin that abruptly gave way to low-density turbidites, then deep-basin deposits in the hyperextended domain. During uppermost Albian to Early Cenomanian time, mantle denudation occurred in the eastern Mauléon Basin and the vergence of the detachment systems reversed. Minor debris-flow deposits formed at the foot of fault scarps associated with the newly formed north-dipping detachments. Elsewhere, sediment from deltaic systems to the west in the Saint-Jean-de-Luz area deposited low-density turbidites in the hyperextended domain. During the post-rift stage, the flux of coarse sediment from the detachment footwall gradually declined as deformation waned, and low-density turbidites expanded onto the hyperextended domain from the European Upper Cretaceous carbonate platform. These paleogeographic reconstructions, in addition to offering a synthetic view of the evolution of sedimentary environments during rifting, offer new insight into the post-rifting exhumation of the lower crust and mantle. Le bassin de Mauléon, localisé dans les Pyrénées nord-occidentales, subit une phase de rifting aboutissant à la dénudation du manteau au cours du Crétacé inférieur. Dans ce travail, nous synthétisons l’évolution des systèmes de dépôts Albien à Cénomanien du bassin de Mauléon. Cette synthèse inclut les lithologies, la répartition régionale, les limites stratigraphiques, les âges et les faciès des différentes formations et membres syn-rifts du bassin de Mauléon. Ces derniers ont été temporellement et spatialement corrélés afin de reconstruire des cartes paléogéographiques offrant une meilleure compréhension: (1) de la distribution 3D des faciès sédimentaires et des systèmes de dépôts de l’Albien au Cénomanien entre la marge proximale ibérique et le domaine hyper-aminci du bassin de Mauléon et (2) du lien entre les principales structures extensives et la sédimentation au cours du rifting et de la dénudation du manteau. De l’Albien inférieur à supérieur, le bassin de Mauléon était essentiellement alimenté depuis la marge proximale ibérique. La forte pente topographique de cette marge, est due à un basculement vers le nord provoqué par le détachement à vergence sud de Saint-Palais. Cette géométrie a favorisé des dépôts de conglomérats de bassin profond au pied de la marge ibérique passant de manière brutale à des faciès hémipélagiques du domaine hyper-aminci. De l’Albien terminal au Cénomanien inférieur, la vergence des systèmes de détachements s’inverse. Cette étape finale de structuration du bassin conduit à la dénudation du manteau dans la partie orientale du bassin. Des debris flows mineurs, issus de l’érosion sous-marine du mur des détachements à vergence nord, sédimentent au pied des escarpements de failles. À la même époque, les turbidites de faible densité, se déposent dans le domaine hyper-aminci, alimentées par un système deltaïque de polarité Ouest-Est provenant du domaine occidental de Saint-Jean-de-Luz. Au cours du stade postrift, les flux sédimentaires grossiers provenant des escarpements des détachements diminuent corrélativement avec la diminution du jeu tectonique sur ces accidents tandis que les turbidites de faible densité se déposent dans le domaine hyper-aminci proviennent de la plateforme carbonatée européenne. En plus d’offrir une vision synthétique de l’évolution des milieux sédimentaires lors du rifting, ces reconstructions paléogéographiques apportent de nouvelles réflexions quant à l’évaluation de l’exhumation de la croûte inférieure et du manteau.

The 4.9 Mw earthquake of 11 November 2019 at Le Teil (France) occurred at a very shallow depth (about 1 km), inducing the surface rupture of La Rouvière fault. The question was raised shortly after about the potential impact of a nearby surface quarry. Thanks to satellite differential interferometry, here, we revealed the existence of a secondary surface rupture of the quasi-parallel Bayne Rocherenard fault. A newly processed seismic cross-section allowed us to shape the three-dimensional geometry of the local three-fault system. Assuming that the earthquake was triggered by the impact of meteoric water recharge, our numerical simulations show that the hydraulic pressure gradient at depth was at a maximum during the period of 2010–2019, just before the seismic event. The estimated overpressure at the intersection of the two faults, which is the most probable place of the hypocenter, was close to 1 MPa. This hydraulic effect is about two and a half times larger than the cumulative effect of mechanical stress release due to the mass removal from the surface quarry over the two past centuries. This work suggests a rapid hydraulic triggering mechanism on a network of faults at a shallow depth after a heavy rainfall episode.

The Western Alps’ active tectonics is characterized by ongoing widespread extension in the highest parts of the belt and transpressive/compressive tectonics along its borders. We examine these contrasting tectonic regimes using a multidisciplinary approach including seismotectonics, numerical modeling, GPS, morphotectonics, fieldwork, and brittle deformation analysis. Extension appears to be the dominant process in the present-day tectonic activity in the Western Alps, affecting its internal areas all along the arc. Shortening, in contrast, is limited to small areas located along at the outer borders of the chain. Strike-slip is observed throughout the Alpine realm and in the foreland. The stress-orientation pattern is radial for σ3 in the inner, extensional zones, and for σ1 in the outer, transcurrent/tranpressional ones. Extensional areas can be correlated with the parts of the belt with the thickest crust. Quantification of seismic strain in tectonically homogeneous areas shows that only 10–20% of the geodesy-documented deformation can be explained by the Alpine seismicity. We propose that, Alpine active tectonics are ruled by isostasy/buoyancy forces rather than the ongoing shortening along the Alpine Europe/Adria collision zone. This interpretation is corroborated by numerical modeling. The Neogene extensional structures in the Alps formed under increasingly brittle conditions. A synthesis of paleostress tensors for the internal parts of the West-Alpine Arc documents major orogen-parallel extension with a continuous change in σ3 directions from ENE–WSW in the Simplon area, to N–S in the Vanoise area and to NNW–SSE in the Briançon area. Minor orogen-perpendicular extension increases from N to S. This second signal correlates with the present-day geodynamics as revealed by focal-plane mechanisms analysis. The orogen-parallel extension could be related to the opening of the Ligurian Sea during the Early-Middle Miocene and to compression/rotation of the Adriatic indenter inducing lateral extrusion.

Flamborough Head chalks are located at the extremities of E-W and N-S trending fault systems along the Yorkshire coast (UK). Rock deformation is expressed in Selwicks Bay where a normal fault is exposed along with a high density of calcite veins. The fault mineralization is tested using geochemistry. Crosscutting relationships are used to differentiate between three vein generations: a network of parallel veins that are oriented perpendicular to stratigraphy (Group I), hydraulic breccia with typical jigsaw puzzle structure (Group II), and a third generation of calcite veins crosscutting the two previous generations (Group III). Geochemical analyses revealed that all three generations possess the same chemical signature and must reflect successive pulses from the same mineralizing fluid source. Strontium isotope analyses showed that the veins have elevated 87Sr/86Sr ratios, that is, up to 7.110, while ratios of the chalk matrix equal 7.707. The latter value is in agreement with the signature of Late Cretaceous seawater. Consequently, the source of the fluid is external, reflecting an open system. The radiogenic Sr-isotope ratios, combined with low iron concentration, suggest that fluids migrated through sandy deposits. Fluid inclusion salinities range from 0 to 12 eq. wt% NaCl equiv. with a dominance of very low salinity inclusions, reflecting a meteoric signal. This leads to a model where meteoric fluids stored in an underlying confined sandstone aquifer were remobilized. The wide range of salinities could result from mixing of the meteoric fluid with some more saline fluids present in the rock sequence or from the dissolution of salts in the subsurface. In addition to the understanding of the local paragenetic evolution of the veining in Flamborough Head chalks, this study offers an insight into the way how fluid flows and mineralizes along fault zones.

Geological planar facets (stratification, fault, joint…) are key features to unravel the tectonic history of rock outcrop or appreciate the stability of a hazardous rock cliff. Measuring their spatial attitude (dip and strike) is generally performed by hand with a compass/clinometer, which is time consuming, requires some degree of censoring (i.e. refusing to measure some features judged unimportant at the time), is not always possible for fractures higher up on the outcrop and is somewhat hazardous. 3D virtual geological outcrop hold the potential to alleviate these issues. Efficiently segmenting massive 3D point clouds into individual planar facets, inside a convenient software environment was lacking. FACETS is a dedicated plugin within CloudCompare v2.6.2 (http://cloudcompare.org/ ) implemented to perform planar facet extraction, calculate their dip and dip direction (i.e. azimuth of steepest decent) and report the extracted data in interactive stereograms. Two algorithms perform the segmentation: Kd-Tree and Fast Marching. Both divide the point cloud into sub-cells, then compute elementary planar objects and aggregate them progressively according to a planeity threshold into polygons. The boundaries of the polygons are adjusted around segmented points with a tension parameter, and the facet polygons can be exported as 3D polygon shapefiles towards third party GIS software or simply as ASCII comma separated files. One of the great features of FACETS is the capability to explore planar objects but also 3D points with normals with the stereogram tool. Poles can be readily displayed, queried and manually segmented interactively. The plugin blends seamlessly into CloudCompare to leverage all its other 3D point cloud manipulation features. A demonstration of the tool is presented to illustrate these different features. While designed for geological applications, FACETS could be more widely applied to any planar objects.

Version moderne de la cartographie géologique 2D, la modélisation géologique 3D est appelée a jouer un rôle fondamental dans l'exécution des missions relevant du Référentiel Géologique de la France. Elle integre des données variées, relatives tant a la surface qu'a la profondeur, et permet une représentation cohérente, bien qu'imparfaite, du sous-sol. Elle permet aussi au (géo) modélisateur de tester et de visualiser des hypotheses de façon a éprouver la pertinence de ses interprétations. Les outils développés et mis en place au BRGM reposent sur des modeles géostatistiques sous-jacents. La méthode du champ de potentiel, simple et flexible, faite de relations géologiques et de champs stochastiques, assure l'intégration des données sous une forme cohérente et permet de chiffrer les incertitudes. Ainsi, loin de s'opposer, l'interprétation du géologue et la représentation stochastique peuvent se nourrir l'une de l'autre.

Version moderne de la cartographie géologique 2D, la modélisation géologique 3D est appelée à jouer un rôle fondamental dans l’exécution des missions relevant du Référentiel Géologique de la France. Elle intègre des données variées, relatives tant à la surface qu’à la profondeur, et permet une représentation cohérente, bien qu’imparfaite, du sous-sol. Elle permet aussi au (géo) modélisateur de tester et de visualiser des hypothèses de façon à éprouver la pertinence de ses interprétations. Les outils développés et mis en place au BRGM reposent sur des modèles géostatistiques sous-jacents. La méthode du champ de potentiel, simple et flexible, faite de relations géologiques et de champs stochastiques, assure l’intégration des données sous une forme cohérente et permet de chiffrer les incertitudes. Ainsi, loin de s’opposer, l’interprétation du géologue et la représentation stochastique peuvent se nourrir l’une de l’autre. Geostatistics for building 3D geological modelsBy updating 2D geological cartography, 3D geological models will play a fundamental role in the Geological Survey of France. Models will be built using varied data on both surfaces and depths in order to make a coherent (but imperfect) representation of the subsoil. Model-builders will test and visualize hypotheses to back up interpretations. The tools designed and used by the Geological and Mining Research Bureau (BRGM) rely on geostatistical models. Based on geological correlations and stochastic fields, the potential field method, simple et flexible, coherently integrates data and assigns coefficients to cases of uncertainty. Far from being opposed, the interpretations made by geologists and stochastic representations can make use of each other.

This chapter presents an overview of the main interpolation methods available in geomodeling software. Different interpolation methods are employed by a wide variety of modeling software products. The chapter provides an overview of the SKUA GOCAD system, and demonstrates how GOCAD tools and procedures may be applied to modeling shallow discontinuous Quaternary stratigraphic units using explicit methods with added stratigraphic rules and constraints. GOCAD was developed to model, manage, and visualize complexly deformed geological surfaces. The development of SKUA‐GOCAD has been mostly focused on solving specific problems related to modeling deformed sedimentary basins and their physical properties. The chapter provides an overview of the Geological Data Management Software Suite and GeoModeller, both developed by the Bureau de Recherches Géologiques et Miniéres (BRGM). In the 1990s, BRGMdeveloped the “Editeur Géologique” to support its geological mapping/modeling activities. The GeoModeller process of 3‐D model creation and validation involves several steps, beginning with the collection of multiple data sources.

the growing range of drug resistant parasitic nematode populations threatens the sustainability of ruminant farming worldwide. In this context, nutraceuticals, animal feed that provides necessary dietary requirements while ensuring parasite control, could contribute to increase farming sustainability in developed and low resource settings. In this study, we evaluated the anthelmintic potential of lupin seed extracts against the major ruminant trichostrongylids, Haemonchus contortus and Teladorsagia circumcincta. In vitro observations showed that seed extracts from commercially available lupin varieties could significantly but moderately inhibit larval migration. This anthelmintic effect was mediated by the seed alkaloid content and was potent against both fully susceptible and multidrug resistant H. contortus isolates as well as a susceptible T. circumcincta isolate. Analytical chemistry revealed a set of four lupanine and sparteine-derivatives with anthelmintic activity, and electrophysiology assays on recombinant nematode acetylcholine receptors suggested an antagonistic mode of action for lupin alkaloids. An in vivo trial in H. contortus infected lupin-fed ewes and goats failed to demonstrate any direct anthelmintic effect of crude lupin seeds but infected lupin-fed goats suffered significantly less parasite-mediated blood losses. Altogether, our findings suggest that the anthelmintic potential of lupin remains limited. However, the potent alkaloids identified could lead to the development of novel drugs or may be used in combination with current anthelmintics to improve their efficacy.

The growing expansion range of drug resistant parasitic nematode populations threatens the sustainability of ruminant farming worldwide. In this context, nutraceuticals, i.e. feed that would both fulfil dietary requirements while ensuring parasite control, would contribute to increase farming sustainability in developed and low resource settings. In this study, we characterized the anthelmintic potential of lupin seed extracts against major ruminant trichostrongylids, i.e. H. contortus and T. circumcincta. Our observations showed that total seed extracts from commercially available lupin varieties significantly inhibited larval migration. This anthelmintic effect was sustained on multidrug resistant field isolate and across parasite species and was mediated by the seed alkaloid content. Analytical chemistry revealed a set of four lupanine and sparteine-derivatives with anthelmintic activity and electrophysiology assays on recombinant nematode acetylcholine receptors suggested an antagonistic mode of action for lupin alkaloids. While commercial lupin seeds did not exert direct anthelmintic effect in H. contortus infected lupin-fed ewes and goats, it significantly dampened blood production losses suffered by goats. Lupin seed extracts hence provide a working basis for the development of novel anthelmintic compounds able to break drug resistance in the field, while they could be used to increase the resilience of infected dairy ruminants.