The significance of the Briançonnais domain in the Alpine orogen is reviewed in the light of data concerning its collision with the active Adriatic margin and the passive Helvetic margin. The Briançonnais which formerly belonged to the Iberian plate, was located on the northern margin of the Alpine Tethys (Liguro-Piémont ocean) since its opening in the early-Middle Jurassic. Together with the Iberian plate the Briançonnais terrane was separated from the European plate in the Late Jurassic-Early Cretaceous, following the northern Atlantic, Bay of Biscay, Valais ocean opening. This was accompanied by the onset of subduction along the northern margin of Adria and the closure of the Alpine Tethys. Stratigraphic and metamorphic data regarding this subduction and the geohistory of the Briançonnais allows the scenario of subduction-obduction processes during the Late Cretaceous-early Tertiary in the eastern and western Alps to be specified. HP-LT metamorphism record a long-lasting history of oceanic subduction-accretion, followed in the Middle Eocene by the incorporation of the Briançonnais as an exotic terrane into the accretionary prism. Middle to Late Eocene cooling ages of the Briançonnais basement and the presence of pelagic, anorogenic sedimentation lasting until the Middle Eocene on the Briançonnais preclude any sort of collision before that time between this domain and the active Adria margin or the Helvetic margin. This is confirmed by plate reconstructions constrained by magnetic anomalies in the Atlantic domain. Only a small percentage of the former Briançonnais domain was obducted, most of the crust and lithospheric roots were subducted. This applies also to domains formerly belonging to the southern Alpine Tethys margin (Austroalpine-inner Carpathian domain). It is proposed that there was a single Palaeogene subduction zone responsible for the Alpine orogen formation (from northern Spain to the East Carpathians), with the exception of a short-lived Late Cretaceous partial closure of the Valais ocean. Subduction in the western Tethyan domain originated during the closure of the Meliata ocean during the Jurassic incorporating the Austroalpine-Carpathian domain as terranes during the Cretaceous. The subduction zone propagated into the northern margin of Adria and then to the northern margin of the Iberian plate, where it gave birth to the Pyrenean-Provençal orogenic belt. This implies the absence of a separated Cretaceous subduction zone within the Austro-Carpathian Penninic ocean. Collision of Iberia with Europe forced the subduction to jump to the SE margin of Iberia in the Eocene, creating the Apenninic orogenic wedge and inverting the vergence of subduction from south-to north-directed.

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The architecture of the Pyrenean‐Cantabrian belt results from the inversion of a series of former Cretaceous rift basins. A HT‐LP metamorphic event dated at 105 to 85 Ma ago is commonly associated with an Albo‐Cenomanian episode of hyperextension of the continental crust. This metamorphism is well known in the eastern Basque‐Cantabrian Basin within the Nappe des Marbres Unit (NMU) that is preserved from intense compressional deformation during the Pyrenean orogeny. Based on a structural study at the scale of the eastern Basque‐Cantabrian Basin and on a dense sampling for TRSCM estimates with the Raman spectroscopy of carbonaceous material (RSCM) method (Raman Spectrometry on Carbonaceous Material), we show following results: (1) the NMU has recorded two major phases of deformation, related to a localized extensional ductile foliation (S1) during the Cretaceous rifting and later by the regional N‐S shortening, recorded by a regional cleavage (S2) observed only in shale sediments. (2) The NMU is affected by early salt tectonics related to several diapirs and salt walls fed by the Upper Triassic evaporitic layer. (3) The NMU recorded maximum temperatures exceeding 550°C, which represent some of the highest temperatures along the Pyrenees. These new data demonstrate that there is no E‐W lateral metamorphic gradient across the belt and that hyperextension rifting occurred consistently within a high‐thermal regime; (4) metamorphic isograds are oblique in respect of the main structures, suggesting that the metamorphic event postdates most of the early salt‐related deformations prior to or coeval with early stages of rifting. As it represents one of the best preserved example of preorogenic hyperextended basin, the eastern Basque‐Cantabrian Basin record may be used regionally to better understand the rift to orogen evolution of the Pyrenean Internal Metamorphic Zone but also more generally as an analog of salt‐bearing hyperextended rift record.

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The formation of sharp cube recrystallization texture after high cold rolling reductions in Fe-36%Ni has been studied by means of X-ray texture measurements and extensive transmission electron microscopy (TEM) observations, including orientation measurements even in highly deformed materials. In contrast to Cu and Al, this material shows only little recovery during cold deformation; therefore, the deformation structure can be studied in detail. After high cold rolling the cube grains present at the hot rolled state show the formation of cells and the development of a large orientation gradient inside cube bands. During recrystallization nucleation of cube grains proceeds at a high rate inside these structures. For low deformations cube grain nucleation seems to be inhibited due to the insufficient orientation gradient across the cells. Regions of other orientations show a much lower nucleation rate owing to their inappropriate microstructure. Thus, other recrystallization textures only develop if the cube nucleation is inhibited.

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In order to constrain the finite deformation pattern of the Variscan basement of the Agly massif, a detailed structural analysis over the whole Agly massif was performed. Our investigation combined geological mapping, reappraisal of published and unpublished data completed with our own structural work. Results are provided in the form of new tectonic maps and series of regional cross-sections through the Agly massif. At variance from previous studies, we identified three deformation fabrics named D1, D2 and D3. The D1 deformation is only relictual and characterized by a broadly northwest-southeast striking and eastward dipping foliation without any clear mineral and stretching lineation direction. D1 might be attributed to thickening of the Variscan crust in a possible orogenic plateau edge position. The D2 deformation is a heterogeneous non-coaxial deformation, affecting the whole massif, that produced a shallowly dipping S2 foliation, and an anastomosed network of C2 shear zones that accommodated vertical thinning and N20 directed extension. D2 is coeval with LP-HT metamorphism and plutonism at ca. 315–295 Ma. D2 corresponds to the extensional collapse of the partially molten orogenic crust in a global dextral strike-slip at the scale of the whole Variscan belt. The D2 fabrics are folded and steepened along a D3 east-west trending corridor, called Tournefort Deformation Zone (TDZ), where the Saint-Arnac and Tournefort intrusives and surrounding rocks share the same NE-SW to E-W subvertical S3 foliation. Along the D3 corridor, the asymmetrical schistosity pattern and kinematic criteria suggest a D3 dextral kinematics. The D3 deformation is a record of E-W striking dextral shearing that facilitated and localized the ascent and emplacement of the diorite and granitic sheet-shaped plutons. D3 outlasted D2 and turned compressional-dominated in response to the closure of the Ibero-Armorican arc in a transpressional regime. The progressive switch from D2 thinning to D3 transpression is attributed to the lessening of gravitational forces at an advanced stage of extensional collapse that became overcome by ongoing compressional tectonic forces at the southern edge of the Variscan orogenic plateau.

The architecture and nature of the continental lithosphere result from billions of years of tectonic and magmatic evolution. Continental deformation over broad regions form collisional orogens which evolution is controlled by the interactions between properties inherited from hits long-lasting evolution and plate kinematics. The analysis of present-day kinematic patterns and geophysical imaging of lithosphere structure can provide clues on these interactions. However how these interactions are connected through time and space to control topographic evolution in collision zones is unknown. Here we explore the case of the Cenozoic mountain building and topographic evolution of Western Europe. We first review the tectono-magmatic evolution of the lithosphere of Europe based on the exploitation of geological, geochronological and geochemical constraints from ophiolites, mafic rocks and xenoliths data. Combined with the analyses of low-temperature thermochronological and plate kinematic constraints we discuss the key controlling parameters of the topography. We show that among the required ingredients is the primary effect of plume-, rift- and subduction-related metasomatic events on lithosphere composition. Those main events occurred during the Neoproterozoic (750-500 Ma) and the late Carboniferous-Permian (310-270 Ma). They resulted in the thinning and weakening of the sub-continental lithospheric mantle of Europe. Contrasting lithosphere strengths and plate-mantle coupling in Western Europe with respect to the cratonic lithosphere of West Africa Craton and Baltica is the first-order parameter that explain the observed strain and stress patterns. Subsequent magmatic and thinning episodes, including those evidenced by the opening of the early Jurassic Alpine Tethys and the CAMP event, followed by late Jurassic and early Cretaceous crustal thinning, prevented thermal relaxation of the lithosphere and allowed further weakening of the European lithosphere. The spatial and temporal evolution of topographic growth resolved by the episodes of increased exhumation show two main periods of mountain building. During the late Cretaceous-early Cenozoic (80-50 Ma) contractional deformation was distributed from North Africa to Europe, but the topographic response to the onset of Africa-Eurasia convergence is detected only in central Europe. The lack of rapid exhumation signal in southern Europe and north Africa reveal that the initial continental accretion in these regions was accommodated under water in domains characterized by thin continental or oceanic crust. The second phase of orogenic uplift period starts at about 50 Ma between the High Atlas and the Pyrenees. This second key period reflects the time delay required for the wider rift systems positioned between Africa and Europe to close, likely promoted by the acceleration of convergence. Tectonic regime then became extensional in northern Europe as West European Rift (WER) opened. This event heralds the opening of the Western Mediterranean between Adria and Iberia at ca. 35 Ma. While mature orogenic systems developed over Iberia at this time, the eastern domain around northern Adria (Alps) was still to be fully closed. This kinematic and mechanical conditions triggered the initiation of backarc extension, slab retreat and delamination in the absence of strong slab pull forces. From about 20 Ma, the high temperature in the shallow asthenosphere and magmatism trapped in the mantle lithosphere contributed to topographic uplift. The first period (80-20 Ma) reveals spatially variable onset of uplift in Europe that are arguably controlled by inherited crustal architecture, superimposed on the effect of large-scale lithospheric properties. The second period marks a profound dynamic change, as sub-lithospheric processes became the main drivers. The channelized mantle flow from beneath Morocco to Central Europe builds the most recent topography. In this study, we have resolved when, where and how inheritance at lithospheric and crustal levels rule mountain building processes. More studies focus on the tectonic-magmatic evolution of the continental lithosphere are needed. We argue that when they are combined with plate reconstructions and thermochronological constraints the relative impact of inheritance and plate convergence on the orogenic evolution can be resolved.