Record details

    Inverse ductile thinning via lower crustal flow and fold-induced doming in the West Carpathian Eo-Alpine collisional wedge
    Jeřábek, Petr
    Lexa, Ondrej
    Plašienka, Dušan
    Schulmann, Karel
Publication type
    článek v periodiku
Source title - serial
    Roč. 31, č. 5
Thesaurus term
    eastern alps
    lateral extrusion
    metamorphic core complexes
    orogen-parallel extension
    p-t conditions
    partial melting equilibria
    tectonothermal evolution
    veporic unit
Abstract (in english)
   Continental core complexes are generally interpreted to result from extensional doming due to gravity-driven upflow of lower crust. In contrast, the Vepor Dome is characterized by the lack of inverted density profile and relatively cold metamorphic field gradient which precludes an activation of Rayleigh-Taylor instability. Instead, the crustal structure of the Vepor Unit is marked by dense and weak metapelitic lower crust and light and strong granitoid upper crust inherited from Variscan nappe stacking. It is shown that the Cretaceous Eo-Alpine tectonic evolution of the Vepor Dome is controlled by the dynamics of two neighboring mechanically strong continental blocks, i.e., the overthrusting of the suprastructural Gemer Unit from the south and the underthrusting of the Fatric basement from the north. Structural, metamorphic and geochronological data from the Vepor Unit imply two main phases of the convergent process: (1) Lower Cretaceous crustal thickening due to overthrusting and int
   ernal deformation of the Gemer Unit together with upper crustal folding in the Vepor Unit led to the progressive development of the orogenic front parallel pressure gradient. The instantaneous response of the lower crustal and low-viscosity metapelites led to an along-strike lower crustal flow accompanied by prograde Barrovian-type metamorphism. (2) As the south vergent underthrusting of the Fatric basement propagated to greater depths during the Upper Cretaceous, the convergent process switched from top driven to bottom driven, and the exhumation of the lower crust occurred via polyharmonic folding. Overall doming of the Vepor Unit induced upper crustal detachment faulting and eastward unroofing of the dome.
    UK Praha, Přírodovědecká fakulta
Contributor code
    UK, PřF
Source format
Import date
    27. 4. 2014