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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.

Humanity is using mineral resources at an unprecedented rate, and demand will continue to grow over the coming decades, fuelled by the energy and digital transitions and the economic development of highly populated countries. But the nature and quantities of mineral resources needed are highly dependent on the types of use envisaged, which vary according to the organisation and level of development of societies. The demand for raw materials must therefore be estimated using a dynamic and regionalised approach, taking into account the different development scenarios, particularly as regards the deployment of renewable or decarbonised energy resources. This article summarises the main analyses of previously published articles by Olivier Vidal et al. [1-4]. [ABSTRACT FROM AUTHOR]

This contribution reviews the challenges of imaging collisional orogens, focusing on the example of the Pyrenean domain. Indeed, important progresses have been accomplished regarding our understanding of the architecture of this mountain range over the last decades, thanks to the development of innovative passive imaging techniques, relying on a more thorough exploitation of the information in seismic signals, as well as new seismic acquisitions. New tomographic images provide evidence for continental subduction of Iberian crust beneath the western and central Pyrénées, but not beneath the eastern Pyrénées. Relics of a Cretaceous hyper-extended and segmented rift are found within the North Pyrenean Zone, where the imaged crust is thinner (10–25 km). This zone of thinned crust coincides with a band of positive Bouguer anomalies that is absent in the Eastern Pyrénées. Overall, the new tomographic images provide further support to the idea that the Pyrénées result from the inversion of hyperextended segmented rift systems.

Author(s): Saleem H. Ali (corresponding author) [1, 2, 3]; Damien Giurco [4]; Nicholas Arndt [5]; Edmund Nickless [6]; Graham Brown [7]; Alecos Demetriades [8]; Ray Durrheim [10]; Maria Amlia Enriquez [...], Successful delivery of the United Nations sustainable development goals and implementation of the Paris Agreement requires technologies that utilize a wide range of minerals in vast quantities. Metal recycling and technological change will contribute to sustaining supply, but mining must continue and grow for the foreseeable future to ensure that such minerals remain available to industry. New links are needed between existing institutional frameworks to oversee responsible sourcing of minerals, trajectories for mineral exploration, environmental practices, and consumer awareness of the effects of consumption. Here we present, through analysis of a comprehensive set of data and demand forecasts, an interdisciplinary perspective on how best to ensure ecologically viable continuity of global mineral supply over the coming decades.

The architecture and tectono-magmatic evolution of the lithosphere of Europe are the result of a succession of subduction, rifting and inputs from plumes that have modified the lithospheric mantle since the Neoproterozoic (750–500 Ma). These events gave birth to contrasting crust-mantle and lithosphere-asthenosphere mechanical coupling between strong, viscous, thick, cold, depleted mantle of the Archean lithosphere of the West African Craton and the East European Craton, and the weak, low viscous, thin, hot and less depleted mantle of the Phanerozoic lithosphere of Central Europe. These differences were long-lived and explain the first-order present-day stresses and topography as well as the styles of orogenic deformation. The lack of thermal relaxation needed to maintain rheological contrasts over several hundreds of millions of years requires high mantle heat flux below Central Europe since at least the last 300 Ma. A combination of edge-driven convection on craton margins and asthenospheric flow triggered by rift propagation during the Atlantic and Tethys rifting is suggested to be the main source of heat. The topography of Central Europe remained in part dynamically supported during most of the Mesozoic thinning in line with the long-term stability of thermal-mechanical structure of the lithosphere. Timing and rates of exhumation recorded across Western Europe during convergence indicate that an additional control by the architecture of Mesozoic rifted margins is required. By 50 Ma the acceleration of orogenic exhumation, from the High Atlas to the Pyrenees, occurred synchronously with the onset of extension and magmatism in the West European Rift. Extension marks the onset of distinct orogenic evolution between Western Europe (Iberia) and the Alps (Adria) in the east, heralding the opening of the Western Mediterranean. A major kinematic re-organisation occurred triggering the involvement of more buoyant and thicker portions of rifted margins resulting in widespread orogenic growth. We conclude that conceptual models of collision require to better account for the thermo-magmatic evolution of the continental lithosphere, especially the original architecture and composition of its mantle, as well as the precise knowledge of the architecture of the rifted margins to explain the timing and rates of orogenic topography.

The present-day tectonic setting of the Western Mediterranean region, from the Pyrénées to the Betics and from the Alps to the Atlas, results from a complex 3-D geodynamic evolution involving the interactions between the Africa, Eurasia and Iberia plates and asthenospheric mantle dynamics underneath. In this paper, we review the main tectonic events recorded in this region since the Early Cretaceous and discuss the respective effects of far-field and near-field contributions, in order to unravel the origin of forces controlling crustal deformation. The respective contributions of mantle-scale, plate-scale and local processes in the succession of tectonic stages are discussed. Three periods can be distinguished: (1) the first period (Tethyan Tectonics), from 110 to 35 Ma, spans the main evolution of the Pyrenean orogen and the early evolution of the Betics, from rifting to maximum shortening. The rifting between Iberia and Europe and the subsequent progressive formation of new compressional plate boundaries in the Pyrénées and the Betics, as well as the compression recorded all the way to the North Sea, are placed in the large-scale framework of the African and Eurasian plates carried by large-scale mantle convection; (2) the second period (Mediterranean Tectonics), from 32 to 8 Ma, corresponds to a first-order change in subduction dynamics. It is most typically Mediterranean with a dominant contribution of slab retreat and associated mantle flow in crustal deformation. Mountain building and back-arc basin opening are controlled by retreating and tearing slabs and associated mantle flow at depth. The 3-D interactions between the different pieces of retreating slabs are complex and the crust accommodates the mantle flow underneath in various ways, including the formation of metamorphic core complexes and transfer fault zones; (3) the third period (Late-Mediterranean Tectonics) runs from 8 Ma to the Present. It corresponds to a new drastic change in the tectonic regime characterized by the resumption of N-S compression along the southern plate boundary and a propagation of compression toward the north. The respective effects of stress transmission through the lithospheric stress-guide and lithosphere-asthenosphere interactions are discussed throughout this period.