Record details

    Crustal influx, indentation, ductile thinning and gravity redistribution in a continental wedge: Building a Moldanubian mantled gneiss dome with underthrust Saxothuringian material (European Variscan belt)
    Chopin, F.
    Corsini, M.
    Dujardin, J. R.
    Edel, J. B.
    Lehmann, J.
    Lexa, Ondrej
    Martelat, J. E.
    Pitra, P.
    Schulmann, K.
    Skrzypek, E.
    Štípská, P.
Publication type
    článek v periodiku
Source title - serial
    Roč. 31, č. 1
Thesaurus term
    chronological constraints
    high-pressure granulites
    large hot orogens
    northeastern bohemian massif
    orlica-snieznik complex
    sw poland
    syn-convergent exhumation
    u-pb ages
    vertical extrusion
Abstract (in english)
   The contribution of lateral forces, vertical load, gravity redistribution and erosion to the origin of mantled gneiss domes in internal zones of orogens remains debated. In the Orlica-Snieznik dome (Moldanubian zone, European Variscan belt), the polyphase tectono-metamorphic history is initially characterized by the development of subhorizontal fabrics associated with medium-to high-grade metamorphic conditions in different levels of the crust. It reflects the eastward influx of a Saxothuringian-type passive margin sequence below a Tepla-Barrandian upper plate. The ongoing influx of continental crust creates a thick felsic orogenic root with HP rocks and migmatitic orthogneiss. The orogenic wedge is subsequently indented by the eastern Brunia microcontinent producing a multiscale folding of the orogenic infrastructure. The resulting kilometre-scale folding is associated with the variable burial of the middle crust in synforms and the exhumation of the lower crust in antiforms. These lo
   calized vertical exchanges of material and heat are coeval with a larger crustal-scale folding of the whole infrastructure generating a general uplift of the dome. It is exemplified by increasing metamorphic conditions and younging of Ar-40/Ar-39 cooling ages toward the extruded migmatitic subdomes cored by HP rocks. The vertical growth of the dome induces exhumation by pure shear-dominated ductile thinning laterally evolving to non-coaxial detachment faulting, while erosion feeds the surrounding sedimentary basins. Modeling of the Bouguer anomaly grid is compatible with crustal-scale mass transfers between a dense superstructure and a lighter infrastructure. The model implies that the Moldanubian Orlica-Snieznik mantled gneiss dome derives from polyphase recycling of Saxothuringian material.
    UK Praha, Přírodovědecká fakulta
Contributor code
    UK, PřF
Source format
Import date
    27. 4. 2014