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Research subject. This article is devoted to the formation features of the Ural-Timan-Paleo-Asian segment of Eurasia. Materials and methods. The research was based on the authors’ data and those obtained following a review of available publications on the geology of segmentation. The Timan region was investigated using the geological information obtained by V.G. Olovyanishnikov.Results. A geodynamic map of the Ural-Timan-Paleo-Asian segment with a scale of 1 : 2 500 000 was compiled, which allowed further research into the structure and formation of the north-western part of the Eurasian area. This part was found to be mostly composed of geodynamic associations of orogens, orogenic systems and orogenic belts of the Upper Proterozoic (Riphean) and Paleozoic time intervals, as well as by elements of the Mesozoic-Cenozoic neoplate. These processes were supplemented by the formation of tectonic systems of superimposed depressions and protoplate protrusions. The formation of orogens, orogenic systems and orogenic belts is associated with the development and subsequent transformation of paleooceanic basins under the conditions of accretion and collision. The terranes of the ancient continental crust also participated in the formation of the segment’s geodynamic elements, for which a typification scheme was proposed. The articles present new data on the formation conditions of the segment’s orogenic elements and the relationship of the orogeny with global reconstructions, including the problem of closing the surrounding oceanic space.

General positions on plate-tectonic metallogeny are presented and the grounds for singling out the metallogenic factors of orogenic systems are given. Mobilistic paradigma corresponds to the genotype of orogens and belts which being formed at the expense of oceanic basin transformations. Their alternative character for the factors of fixistic constructions is stressed. The conclusion is made that as a theoretical basis for the analysis of orogen system metallogeny - that is the metallogeny of considering in the paper segment - are the metallogenic factors connected with processes of movement and dislocation of lithospheric plates, geodynamical regimes of riftogenic extension and spreading of plates, geodynamical environments of subduction, accretion and collision. A decisive role of the factor of movement and dislocation of lithospheric plates makes it possible to introduce for this type of metallogeny the denomination of plate-tectonic metallogeny . A comparative analysis of metallogeny of modern oceanic basins and of epioceanic orogens showed that metallogenetic factors of geodynamical environments characterize their ore specialization, while the accretions and collisions define the location of ore concentrations, determining, in the long run, combination in orogenic systems of pre-accretion, accretion and post-accretion metallogenic elements. On the given basis taking into account regional particularities the metallogeny analysis of Ural-Timan-Paleoasian segment of Eurasia has been made. Diagrams of metallogeny and the segment metallogenic zoning were suggested.

A long-standing challenge in tectonics is to evaluate the role of inheritance and define the initial conditions of a geodynamic system, which are prerequisites to understand and model its evolution with some accuracy. Here we revisit the concept of “inheritance” by distinguishing “interface shape inheritance”, which includes the transient thermal state and gravitational potential energy, and “persisting inheritance”, which encompasses long-lasting structural and compositional inheritance. This new approach allows us to investigate, at each stage of a Wilson Cycle, the interplay between inheritance (innate/“genetic code”) and the physical processes at play (extension/compression, magmatism etc.). The aim of this paper is to provide a conceptual framework that integrates the role of inheritance in the study of rifts, rifted margins and collisional orogens based on the work done in the OROGEN project, which focuses on the Biscay-Pyrenean system. The Biscay-Pyrenean rift system resulted from a multistage rift evolution that developed over a complex lithosphere pre-structured by the Variscan orogenic cycle. There is a general agreement that the Pyrenean-Cantabrian orogen resulted from the reactivation of an increasingly mature rift system along-strike, ranging from mature rifted margins in the west to an immature and segmented hyperextended rift in the east. However, different models have been proposed to explain the preceding rifting and its influence on the subsequent reactivation. Results from the OROGEN project highlight the sequential reactivation of rift-inherited decoupling horizons and identify the specific role of exhumed mantle, hyperextended and necking domains during compressional reactivation. They also highlight the contrasting fate of rift segment centres versus segment boundaries during convergence, explaining the non-cylindricity of internal parts of collisional orogens. Results from the OROGEN project also suggest that the role of inheritance is more important during the initial stages of collision, which may explain the higher complexity of internal parts of orogenic systems with respect to their external parts. In contrast, when the system involved in the orogeny is more mature, the orogenic evolution is mostly controlled by first-order physical processes as described in the Coulomb Wedge theory, for instance. This may account for the simpler and more continuous architecture of external parts of collisional orogens and may also explain why most numerical models can reproduce mature orogenic architectures with a better accuracy compared to those of initial collisional stages. The new concepts developed from the OROGEN research are now ready to be tested at other orogenic systems that result from the reactivation of rifted margins, such as the Alps, the Colombian cordilleras and the Caribbean, Taiwan, Oman, Zagros or Timor.

In the Central Mediterranean the Africa-Eurasia convergence led to the development of complex orogenic systems and back-arc basins. Throughout Pliocene-Quaternary times the Southern Apennines accretionary prism migrated toward the Apulia foreland and, contemporaneously, the Tyrrhenian Sea back-arc basin opened. In this study, we investigated the offshore of the southern Apulia foreland and the Southern Apennines. Using seismic reflection profiles and well data in a dedicated GIS software, we made a detailed stratigraphic analysis, reconstructed the structural pattern, and built 2-D geological models of the main geological surfaces. The structure of the Apulia region formed during two main tectonic stages: lower Pleistocene complex extensional faulting developed in a transtensional regime and middle-upper Pleistocene transpression/shortening. The Southern Apennines accretionary prism developed through the Pliocene-early lower Pleistocene and was overprinted by late lower Pleistocene-middle Pleistocene NW-SE sinistral faults. Through linking new data from the accretionary prism and the foreland with previous information from the Tyrrhenian Sea back-arc, we provide an original interpretation for the relationships between the various provinces that make the Central Mediterranean crustal puzzle and reconstruct the main phases of the evolution of its Pliocene-Quaternary orogenic cycle. We recognized collisional stages of uncoupled plates, followed by late lower-middle Pleistocene postcollisional stages of coupled continental plates. This Pleistocene plate reorganization of Central Mediterranean was probably due to the rupture of the Apulia/Ionian slab or to NNW intraplate shortening transmitted from Africa. [ABSTRACT FROM AUTHOR]

[Display omitted] • Documents new digital plate and province models for GIS, GMT, and GoogleEarth. • Updated plate model correlates well with GPS, earthquakes, volcanoes, topography. • Global plate and province model includes crust type, province type, and last orogeny. • System-based orogen model shows good correlation with metamorphic and igneous dates. • Includes 16 major plates, 54 microplates, 73 deformation zones, and 899 provinces. Accurate spatial models of tectonic plates and geological terranes are important for analyzing and interpreting a wide variety of geoscientific data and developing compositional and physical models of the lithosphere. We present a global compilation of active plate boundaries and geological provinces in a shapefile format with interpretive attributes (e.g., crust type, plate type, province type, last orogeny). The initial plate and province boundaries are constructed from a combination of published global and regional models that we refine using a variety of geoscientific constraints including, but not limited to, relative GPS motions, earthquakes, mapped faults, potential field characteristics, and geochronology. These new plate model show improved correlation to observed earthquake and volcano occurrences within deformation zones and microplates, compared to existing models, capturing 73 and 80% of these criteria, respectively. Deformation zones and microplates only account for 16% of Earth's surface area. We estimate 57.5% of the Earth's surface is covered by oceanic crust, which is a slight increase relative to the most recent seafloor age model. The model of last orogenies agrees well with peaks in the globally summed geochronology data. There is room for improvement in future editions of our global plate and geologic provinces model where basins, ice, or lack of geological data fidelity obscure bedrock geology, particularly in the eastern Central Asian Orogenic Belt, much of Africa, East Antarctica, and eastern Australia. Additionally, some province types—orogens, shields, and cratons that are homogenized within our global scheme—can likely be partitioned into smaller terranes with more precise geodynamic attributes. Despite some of these shortcomings, the digital maps presented here form a self-consistent data standard for adding spatial metadata to geoscientific databases. The database is available on GitHub where the geoscience community can provide updates to improve the models and their contemporaneity as new knowledge is acquired. The files are also released in formats suitable for use in Generic Mapping Tools and GoogleEarth. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews the research history and progress in the study of accretionary orogenesis, and concludes that accretionary orogenesis is the fundamental process of continental evolution throughout Earth''s history. According to the authors'' point of view, the formation and evolution of orogenic belts can be explained by the evolution of composite island arc-basin systems along active continental margins. The formation of still larger orogenic systems is closely related to composite island arc-basin systems formed on one or two sides of an ocean, and controlled by the subduction of long-lived oceanic lithosphere. Accretionary orogenic systems in active continental margins are built up by a series of collisional and accretionary orogenies, including arc-arc and arc-continent collision, and the accretion of forearc and backarc subduction complexes, tectonic collages of oceanic plateaus/islands/seamounts, and exotic blocks (terranes). Convergent crustal consumption zones (sutures) are formed when the long-lived ocean lithosphere is eventually eliminated. Large orogenic complexes formed due to the amalgamation of orogenic systems transformed from composite island arc-basin systems on both sides of long-lived ocean. Subsequently such large orogenic complexes are overprinted by the effects of continent-continent collision and intracontinental compression/extension, which make the orogenic processes still more complex. The convergent crustal consumption zone, therefore, is the key to understand the formation and evolution of orogenic systems. All kinds of orogenic processes of composite island arc-basin systems in active continental margins are actually the consequences of accretionary orogenesis. The study of composite island arc-basin systems is essential to understand the components, textures and structures of orogenic systems. Postorogenic intracontinental tectonic evolution is also controlled by the evolutionary histories of composite island arc-basin systems. Composite island arc-basin systems and continental margin systems provide more comprehensive records of Wilson cycle than fossil oceanic lithosphere. According to the ideas of composite island arc-basin systems, a new model for the evolution of the Tethyan ocean is proposed, specifically that the Gangdese belt (Lhasa terrane) was initially controlled by the southward subduction of the Tethyan oceanic lithosphere in the Carboniferous, that an accretionary orogeny took place in the Triassic, and that the Tethyan ocean vanished by the end of Early Cretaceous. [Copyright &y& Elsevier]