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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In the Lesser Caucasus three main domains are distinguished from SW to NE: (1) the autochthonous South Armenian Block (SAB), a Gondwana-derived terrane; (2) the ophiolitic Sevan-Akera suture zone; and (3) the Eurasian plate. Based on our field work, new stratigraphical, petrological, geochemical and geochronological data combined with previous data we present new insights on the subduction, obduction and collision processes recorded in the Lesser Caucasus. Two subductions are clearly identified, one related to the Neotethys subduction beneath the Eurasian margin and one intra-oceanic (SSZ) responsible for the opening of a back-arc basin which corresponds to the ophiolites of the Lesser Caucasus. The obduction occurred during the Late Coniacian to Santonian and is responsible for the widespread ophiolitic nappe outcrop in front of the suture zone. Following the subduction of oceanic lithosphere remnants under Eurasia, the collision of the SAB with Eurasia started during the Paleocene, producing 1) folding of ophiolites, arc and Upper Cretaceous formations (Transcaucasus massif to Karabakh); 2) thrusting toward SW; and 3) a foreland basin in front of the belt. Upper-Middle Eocene series unconformably cover the three domains. From Eocene to Miocene as a result of the Arabian plate collision with the SAB to the South, southward propagation of shortening featured by folding and thrusting occurred all along the belt. These deformations are sealed by a thick sequence of unconformable Miocene to Quaternary clastic and volcanic rocks of debated origin.

Late Carboniferous^Early Tertiary apparent polar wander (APW) paths (300^40 Ma) for North America and Europe have been tested in various reconstructions. These paths demonstrate that the 500 fathom Bullard et al. fit is excellent from Late Carboniferous to Late Triassic times, but the continental configuration in northern Pangea changed systematically between the Late Triassic (ca. 214 Ma) and the Mid-Jurassic (ca. 170 Ma) due to pre-drift extension. Best fit North Atlantic reconstructions minimize differences in the Late Carboniferous^Early Jurassic and Late CretaceousT ertiary segments of the APW paths, but an enigmatic difference exists in the paths for most of the Jurassic, whereas for the Early Cretaceous the data from Europe are nearly non-existent. Greenland's position is problematic in a Bullard et al. fit, because of a Late Triassic^Early Jurassic regime of compression ( s 300 km) that would be inherently required for the Norwegian Shelf and the Barents Sea, but which is geologically not defensible. We suggest a radically new fit for Greenland in between Europe and North America in the Early Mesozoic. This fit keeps Greenland`locked' to Europe for the Late Paleozoic^Early Mesozoic and maintains a reconstruction that better complies with the offshore geological history of the Norwegian Shelf and the Barents Sea. Pre-drift (A24) extension amounted to approximately 450 km on the Mid-Norwegian Shelf but with peak extension in the Late Cretaceous.

On the basis of a section across the northwestern Alpine wedge and foreland basin, analogue modeling is used to investigate the impact of surface processes on the orogenic evolution. The basis model takes into account both structural and lithological heritages of the wedge. During shortening, erosion and sedimentation are performed to maintain a critical wedge. Frontal accretion leads to the development of a foreland thrust belt; underplating leads to the formation of an antiformal nappe stack in the internal zones. Important volumes of analogue materials are eroded out of the geological record, which in the case of the Alps suggests that the original lengths and volumes may be underestimated. The foreland basin evolves differently depending on the amounts of erosion/sedimentation. Its evolution and internal structuring is governed by the wedge mechanics, thought to be the main controlling mechanism in the development of the Molasse basin in a feedback interaction with surface processes.

The Greater Caucasus is Europe's highest mountain belt and results from the inversion of the Greater Caucasus back-arc-type basin due to the collision of Arabia and Eurasia. The orogenic processes that led to the present mountain chain started in the Early Cenozoic, accelerated during the Plio-Pleistocene, and are still active as shown from present GPS studies and earthquake distribution. The Greater Caucasus is a doubly verging fold-and-thrust belt, with a pro-and a retro wedge actively propagating into the foreland sedimentary basin of the Kura to the south and the Terek to the north, respectively. Based on tectonic geomorphology -active and abandoned thrust fronts -the mountain range can be subdivided into several zones with different uplift amounts and rates with very heterogeneous strain partitioning. The central part of the mountain range -defined by the Main Caucasus Thrust to the south and backthrusts to the north -forms a triangular-shape zone showing the highest uplift and fastest rates, and is due to thrusting over a steep tectonic ramp system at depth. The meridional orogenic in front of the Greater Caucasus in Azerbaijan lies at the foothills of the Lesser Caucasus, to the south of the Kura foreland basin.

The Tertiary development of the Norwegian continental margin was dominated by the opening of the Arctic-North Atlantic Ocean. The correct identification of magnetic anomalies and their ages and the analysis of spreading rates during the formation of this ocean are important in understanding the development of the region and specifically the history of its passive margins. Three ocean domains, the AEgir, Reykjanes and Mohns regions, were investigated in an effort to understand the lateral changes in structural development of the passive margin after continental break-up. Spreading rates generally slowed down from 2 cm a À1 after Early Eocene initiation of sea-floor spreading, to values around 0.5 cm a À1 in Oligocene time. An increase in spreading rates to around 1 cm a À1 coincided with the positioning of the Iceland hotspot under the North Atlantic mid-ocean ridge. At the same time, the European plate changed its absolute plate motion from a north-directed drift to a motion more towards the east. The location of inversion structures in the Vøring and Faeroes Basin rather than in the Møre Basin is related to differences in spreading rates. The Mohns and the Reykjanes Ridges produced more ocean floor than the AEgir-Kolbeinsey Ridges. Asymmetric ocean-floor formation in the AEgir Ridge led to differential stress at the base of the lithosphere, which probably explains the absence of inversion features in the Møre Basin (less mantle drag). Furthermore, upper plate margins such as the Vøring Basin and possibly the Faeroe Basin have a lower compressional strength than lower plate margins such as the Møre Basin, and therefore preferentially developed inversion structures. Along the transform boundaries separating the domains, additional stress probably built up along extension of the transform zones into the extended continental crust. This additional stress probably also assisted initiation of the inversion structures in the Vøring Basin and the Faeroes area. The amplification of the inversion structures in the Vøring Basin and the Faeroes Basin was subsequently caused by a variety of processes related to sedimentation and uplift-erosion.

The western Alps form a geodynamically active mountain belt showing the typical features of an evolving orogenic wedge with its pro-wedge geometry to the NNW and its retro-wedge structures to the SSE. Renewed tectonic underplating of European continental crust occurred after the orogenic wedge underwent major dynamic disequilibrium following the break-off of the southward subducting slab of the European passive margin. The most important of these basement imbricates are the Mont-Blanc-Aiguilles Rouges and Gastern-Aar crystalline massifs, also forming the Alps' highest mountains. The upper plate-present-day orogenic wedge of the western Alps includes the Molasse basin and the Jura fold-and-thrust belt, both decoupled from the basement over a basal de ´collement surface. The overall geometry of this wedge appears to be strongly unstable according to simple wedge models. In its attempt to regain stability, out-of-sequence thrusts form in the existing basement nappes; but also new basement nappes should develop beneath the southern portion of the Molasse basin. New out-of-sequence thrusts in the cover, trigger higher than average uplift rates concentrated around the newly forming structures and are accompanied by a concentration of earthquakes. Tectonic underplating is further corroborated by neotectonics and the tectonic structures observed in the Pre ´alpes, Molasse basin and Jura. Similarly, uplift rates, and earthquakes along the southern edge of the Jura mountains seem to witness the development of a new=incipient basement nappe at depth (partial inversion of former Permo-Carboniferous grabens in the basement). A possible spatial coincidence of areas with strong earthquake activity and zones with uplift rates above surrounding values, suggest a common mechanism for their origin in the western Swiss Alpine foreland. Combined with information from basement geometry and wedge dynamics it is proposed that the common mechanism is the development of basement imbricates by tectonic underplating. The proposed model for ongoing and possible future tectonic underplating beneath an active Alpine orogenic wedge also allows to reconcile the models of basement=wrench-faulting in the Molasse basin and Jura with the distant push theory, where the Molasse basin and Jura develop over a basal de ´collement horizon.