Podrobnosti záznamu

    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, Michel
    Dujardin, Jean Rémy
    Edel, Jean-Bernard
    Lehmann, Jeremie
    Lexa, Ondrej
    Mertelat, Jean-Emmanuel
    Pitra, Pavel
    Schulmann, Karel
    Skrzypek, Etienne
    Štípská, Pavla
Typ dokumentu
    článek v periodiku
Zdrojový dokument - seriál
    Roč. 31, č. TC1013
Výraz tezauru
    high-pressure granulites, Orlica-Snieznik Complex, large hot orogens, northeastern Bohemian Massif, syn-convergent exhumation, U-Pb ages, SW Poland, vertical extrusion, pre-Variscan, chronological constraints
Klíčové slovo
Abstrakt (anglicky)
   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.
    Česká geologická služba
Kód přispěvatele
    ČGS (RIV)
Zdrojový formát
Datum importu
    15. 10. 2014