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Deformation in intraplate domains is usually considered as a consequence of tectonic events at plate boundaries. Nevertheless, the occurrence of intraplate earthquakes such as the recent Le Teil event in the south of France along the Cévennes Fault System (CFS), on 11 November 2019, Mw = 4.9, questions whether this far-field deformation only occurs during tectonic pulses at plate boundaries, or if it corresponds to low-intensity but regional continuous deformation through time. To address this question, we have coupled U–Pb geochronology of fault-related calcites with structural analysis along a major fault system (the CFS) in the South-East Basin, France. We evidence (1) an Albian activity of the CFS and (2) a continuous compressional activity of the CFS and satellite structures during the whole Eocene and probably during the Late Cretaceous – Palaeocene, including periods (e.g. Lutetian) usually considered as phases of tectonic quiescence. We thus demonstrate that the tectonic reactivation of this intraplate fault system is not restricted to periods of high rates of deformation at plate boundaries.

In Western Europe, the deformations related to the opening of the Bay of Biscay and the formation of the Pyrenean belt are well described in the southern part of the Aquitaine Basin, but little is known about the impact of these geodynamic events towards the Northern Aquitaine Platform. In this paper, we combine field observation with Unmanned Aerial Vehicle (UAV) imagery and calcite U-Pb geochronology to determine precisely the tectonic evolution in the Vendée Coastal domain. We evidence two main tectonic events: (1) At the transition between the Late Jurassic to Early Cretaceous, WNW-ESE striking normal faults formed horsts and grabens at the onset of the opening of the Bay of Biscay. The reactivation of Variscan faults during this tectonic event is consistent with oblique extension. This event triggered ascending fluid flows that mix with Basin fluids responsible for barite-pyrite-quartz mineralizations near the unconformity. (2) During the Late Cretaceous, fractures, wide-open folds, veins, and joints are consistent with the N-S shortening direction during the earliest stages of the Pyrenenan compression. In both cases, the Northern Aquitaine Platform records the early stages of the main regional tectonic events in a far-field position. In the northern Aquitaine Basin, as in many other places in Europe, the tectonic study of sedimentary platforms located far from the plate boundaries provides new constraints on the early diffuse deformation process that predate the main tectonic phases.

The Eocene–Oligocene boundary was a period of major global climatic and tectonic change, yet its expression in the Zagros Foreland Basin remains controversial due to complex facies relationships and the overprint of the Pyrenean orogenic phase. This study aims to resolve this stratigraphic enigma across three key sections using an integrated multi‐proxy approach combining biostratigraphy, geochemistry and mineralogy from 670 thin sections and 30 geochemical samples. The multi‐proxy approach provides independent, cross‐validated lines of evidence for interpreting depositional environments and sequence boundaries, moving beyond correlation based on lithostratigraphy alone. Results delineate two distinct boundary expressions. In the interior Fars, an erosional unconformity separates the Lutetian Orbitolites complanatus‐Coskinolina roberti‐Rhapydionina liburnica zone of the Jahrum Formation from the Rupelian Nummulites vascus‐N. fichteli zone of the Asmari Formation. In coastal Fars, a continuous transition is marked by the Late Eocene Turborotalia cerroazulensis‐Hantkenina zone of the Pabdeh Formation grading into the Rupelian Asmari. Geochemical data validate these models: the Pabdeh Formation shows high CaO and Sr. with low Al2O3, indicating a pelagic setting, while the Jahrum Formation has higher terrigenous proxies. SEM‐EDS confirms syngenetic dolomitisation in the interior platform and pyrite framboids in the basinal Pabdeh, indicating anoxia. A Monte Carlo sensitivity analysis confirms 97.3% confidence for the unconformity and 89.4% for the conformable interpretation. This work quantitatively demonstrates that a paleobathymetric gradient was the dominant control on sequence architecture, effectively neutralising the Pyrenean tectonic signal in deeper basinal settings. This framework provides a predictive model for stratigraphic correlation in foreland basins globally. New bio‐sequence framework for the Eocene–Oligocene transition in Zagros. Geochemical data validate basin depth control on SB1 vs. SB2 boundaries. SEM‐EDS analyses confirm subaerial exposure versus continuous deposition. Sensitivity analysis quantifies sub‐10% uncertainty in stratigraphic interpretations. Resolves the Pyrenean orogeny's variable impact across the Fars paleo‐platform.

Stratigraphic grain-size trends record tectonic and climatic signals. Here, we show how measurements of sediment calibre and clast lithology can be used to identify changes in accommodation space and sediment budget, using examples from Palaeogene syntectonic clastic deposits in the southern Pyrenees. We identify a mid Eocene interval of rapid grain-size fining, driven by local tectonic subsidence; a late Eocene interval of diminished local accommodation generation; and an Oligocene interval showing order-of-magnitude lower grain-size fining rates, driven by increased sediment supply. Our results demonstrate that grain-size trends provide a powerful means to explore the tectonic and climatic boundary conditions governing sediment routing systems.

Orogenic processes encompass a complex interplay of deformation and metamorphic events, which can impact the formation of ore deposits to various degrees. However, distinguishing fluid signatures from orogenic versus post-orogenic events presents a significant challenge due to the scarcity of robust geochemical indicators that remain unaffected during multiple post-mineral reworking events. This study carefully examines the properties and chemistry of primary and secondary fluid inclusions (FIs), identifying distinct signatures of two fluid populations linked to different styles of Pb-Zn mineralization in the Pyrenean Axial Zone (PAZ) of Southern-France/Northern-Iberia: These included late-Carboniferous stratabound epigenetic Pb-Zn deposits and Mesozoic crosscutting Pb-Zn(-Ge) vein systems. Population (I) is identified in primary and secondary FIs in a few crosscutting Pb-Zn veins and constitutes a minor component in stratabound epigenetic bodies. It exhibits Na-dominated low to intermediate salinity (< 20 wt% NaCl eq.), intermediate temperatures (200–350 °C), abundant CO 2 -rich FIs and shows low homogeneous Cl/Br molar ratios. These characteristics are consistent with a metamorphic origin of the fluids, associated with Late-Variscan metamorphism. Population (II) is commonly observed in the crosscutting vein systems where it occurs as primary and pseudosecondary FIs, as well as in stratabound epigenetic bodies where it represents the main fluid component of secondary FIs. Population (II) is Ca-dominated with intermediate to high salinity (15–35 wt% NaCl eq.), relatively low temperature (< 200 °C), and shows high Cl/Br molar ratios with significant variations. This last characteristic is typical of mixing of at least two fluids, one with a probable low Cl/Br molar ratio at shallow crustal levels and another with high Cl/Br molar ratio at deeper levels. Characteristics of population (II) are consistent with a fluid of basinal origin that interacted with the basement while circulating in the Pyrenees during the Mesozoic, although a Pyrenean-Alpine age cannot be excluded. Locally, in sphalerite-hosted secondary FIs that form trails in the crosscutting veins, we find evidence of high Ge concentrations (up to few 1000s ppm), which correlate with anomalous Pb and Tl concentrations. Very high metal concentrations (up to 1–2 wt% Pb, Zn), which are inversely proportional to Cl/Br molar ratios, are found in FIs mainly within veins hosted in deep-seated high-grade metamorphic rocks. Based on a compilation of fluid data from the literature, a first-order correlation can be deduced between the metamorphic grade of the rocks hosting the mineralization and the Pb and Zn content in the FIs. Early stratabound orebodies are considered likely sources of metal for the development of the late crosscutting vein mineralization. This study demonstrates the significance and complexity of orogen-scale fluid circulation and supports the importance of pre-existing metal enrichment in the crust, especially in high-grade metamorphic rocks as a prerequisite for the formation of Pb-Zn veins in complex multi-stage orogens. Highlights Two fluid populations with distinct fluid inclusion types, salinity, temperatures, Ca-Sr and halogen concentrations. Population (I) has a low to medium salinity and high temperature (250–350 °C). Population (II) has a medium to high salinity and low temperature (< 200 °C). The low Cl/Br molar ratios in population (I), along with its Ca-poor and CO 2 -rich characteristics, are indicative of metamorphic fluids. The high and variable Cl/Br molar ratios in population (II), along with its Ca-rich and CO 2 -poor characteristics, evidence a major basinal fluid flow. Correlation between metamorphic grades, Pb-Zn concentration in fluid and Cl/Br ratio. Germanium is locally observed concentrated in Pb-Tl rich sulfosalts phases hosted in FIs trails that intersect deformed sphalerite.

By demonstrating that extensional inheritance plays a decisive role in the formation of orogens, recent studies have questioned the ability of a unique, complete Wilson cycle model to explain the diversity of collisional orogens. For 5 years, the OROGEN Research Project had therefore the ambition to challenge this classical Wilson cycle model. By focusing on the diffuse Africa-Europe plate boundary in the Biscay-Pyrenean-Western Mediterranean system, the project questioned the preconceived \"Orogen singularity\" assumption and investigated the role of divergent and convergent maturities in orogenic and post-orogenic processes. This work led us to rethink the development of collisional orogens in a genetic (or process-driven) way and to propose an updated version of the \" classical Wilson cycle\", the Wilson Cycle 2.0, and the ORO-Genic ID concept presented in this paper. The particularity of the Wilson Cycle 2.0 is to take into account the divergence and convergence maturity reached during extensional and orogenic processes in proposing different tectonic tracks associated with different ORO-Genic ID numbers. The ORO-Genic ID is composed of a letter (or track), corresponding to the maturity of divergence reached and a number corresponding to the maturity of convergence reached during the formation of the orogen. This new concept relies on the observed pre- and syn-convergent tectono-stratigraphic and magmatic record and deformation history and can be identified in using diagnostic criteria presented in this paper. It represents therefore a powerful tool that can be used to characterize the evolution and the architectural type of an orogenic system. Moreover, as a mappable concept, it can be easily used worldwide and can help us to explain differences in the style of deformation at crustal scale between orogens.

The Cabuérniga Fault System (CFS) extends for 150 km in E-W trend along the northern divide of the Cantabrian Mountains, near the Cantabrian Sea. This fault system was reactivated several times since the Paleozoic, and displays hydrothermal activity nowadays. We present here a detailed geological map of the whole CFS and six cross-sections distributed along strike, which allowed us to unravel the kinematic history of the individual fault segments comprising the CFS. The current CFS geometry mainly results from the reactivation of E-W Variscan thrusts and NW-SE Late-Variscan strike-slip faults during the Alpine Cycle. Reactivation took place in relation to both Permian and Mesozoic pre-orogenic extension and subsequent Cenozoic shortening. The eastern end of the CFS corresponds to a N-S structure arriving at the Cantabrian coast, while the western edge connects with the E-W trending Llanera fault, leading to an Alpine fault system extending 220 km.

During orogenesis, large-scale thrusts as orogenic fronts can act as conduits and/or barriers for fluid flow. Unravelling the timing and modes of tectonic activation of large-scale faults is crucial to understanding the relationship between fluid flow and deformation. The North Pyrenean Frontal Thrust (NPFT) corresponds to a major basement-involved thrust responsible for the northward overthrust of the pre-orogenic sediments on top of the Aquitaine Foreland Basin. This study questions the timing of activation of this thrust, its geometry, the nature of the last fluids, which circulated there, and its role on the circulation of fluids. The structural study confronted to published thermochronology data led to determine the timing of the two tectonic activations during the NPFT compression phase and to relate them to the fluid circulations. We constrain the first activation at Campanian times and link it to the leak of the deep gas reservoir present in depth, as the NPFT acted as a conduit. Then the NPFT acted as a barrier, probably due to the breccia consolidation during the Paleocene quiescence period. Finally, the Eocene-Oligocene reactivation led to fluid circulation of high salinity fluids from the Triassic evaporites leaching. This latter event is associated with a fracturing event and the late generation of calcite veins studied here. This is the first study in the Pyrenees directly applied to the NPFT which uses the association between fluid inclusions study, seismic and thermochronological data. It highlights that the NPFT may be an important structure responsible of the leakage of deep hydrocarbons reservoirs. It also shows the importance of the determination of the activation steps of large-scale faults to decipher the origin of fluid circulations in space and time. Au cours d’une orogenèse, les chevauchements majeurs en tant que fronts orogéniques peuvent agir comme conduits et/ou barrières pour la circulation de fluides. Il est essentiel de comprendre la chronologie et le mode d’activation de telles failles à grande échelle, pour comprendre la relation entre les circulations fluides et la déformation. Le Chevauchement Frontal Nord Pyrénéen (CFNP) correspond à un chevauchement majeur ancré dans le socle et responsable du chevauchement vers le nord des sédiments pré-orogéniques au sommet du Bassin d’avant-pays Aquitaine. Cette étude interroge le timing d’activation de ce chevauchement, sa géométrie, la nature des derniers fluides qui y ont circulé et son rôle dans la mise en circulation de ces fluides. L’étude structurale confrontée à des données de thermochronologie déjà publiées, a conduit à déterminer la chronologie des deux activations tectoniques de la phase de compression du CFNP et à les relier aux circulations fluides. Nous contraignons la première activation au Campanien et a probablement conduit à la fuite du réservoir de gaz présent en profondeur, le CFNP jouant le rôle de conduit. Ensuite, il a agi comme une barrière, probablement en raison de la consolidation de la brèche pendant la période de quiescence du Paléocène. Enfin, la réactivation Eocène-Oligocène a conduit à une circulation de fluides très salés issus du lessivage des évaporites du Trias. Ce dernier événement est associé à un événement de fracturation et à la génération tardive des veines de calcite étudiées ici. Il s’agit de la première étude dans les Pyrénées directement appliquée au NPFT qui utilise une association entre étude des inclusions fluides et données sismiques et thermochronologiques. Elle met en évidence que le NPFT peut être une structure importante responsable de la fuite des réservoirs d’hydrocarbures profonds. Elle montre également l’importance de la détermination des étapes d’activation des chevauchements de grande échelle pour déterminer l’origine des circulations fluides dans l’espace et le temps.

The Pyrenees are an Alpine chain, located between France and Spain. This map covers 592 km 2 (27 × 22 km) at 1:40,000 scale of the Central Pyrenees. The map comprises the South Pyrenean Zone, an Upper Cretaceous to Paleogene succession of complex thrust-fold systems, southward directed and the southern border of the Axial Zone, mainly deformed in the Variscan Orogeny. In the Axial Zone, the map reflects kilometric interference fold patterns as a result of Alpine and Variscan fold superimposition, with characteristic crescent and mushroom shapes, recognized for the first time in the cartography of this region.