Petrogenesis and geochronology of a post-orogenic calc-alkaline magmatic association: the Žulová Pluton, Bohemian Massif

Abstract

The Žulová Composite Pluton located at the north-eastern margin of the Bohemian Massif exposes undeformed coexisting mafic-felsic association typical of post-orogenic magmatism. The bulk of the pluton is made of biotite granite and granodiorites along with subordinate quartz monzodiorite. New LA-ICP-MS U-Pb zircon dating revealed a synchronous emplacement of the biotite granite (291 ± 5 Ma), granodiorite and quartz monzodiorite (292 ± 4 Ma). The whole-rock geochemistry and the Sr-Nd isotopic data indicate that a plausible source for the biotite granite and the granodiorite could have been a lithologically inhomogeneous pile of Devonian arc-derived, immature metagreywackes interbedded with volcaniclastics. Melting of this crustal material was probably triggered by the rise of hot basic (quartz monzodioritic) magma which could have been an enriched mantle-derived melt contaminated by the underlying Cadomian basement. The Žulová Composite Pluton is a part of a Late Carboniferous-Early Permian Sudetic Granite Belt, including in addition three large plutonic complexes distributed along major terrane boundaries: the Krkonoše-Jizera, the Strzegom-Sobótka and the Strzelin massifs. The genesis of this magmatic belt was likely induced by the rise of hot mantle-derived magma in the crust while their spatially and temporally discrete emplacement at shallow levels was probably related to the (extensional) reactivation of lithospheric discontinuities at terrane boundaries. Former orogenic wedges, resulting from the inversion of youthful plate margins, represent a feasible fertile source for such post-orogenic granitoids.

Last stage of Variscan granitoid magmatism in the Strzelin Massif (SW Poland): petrology and age of the biotite-muscovite granites

“…These granitoids were dated by var i ous tech niques at 324-283 Ma (Turniak et al, 2006;Pietranik and Waight, 2008;Oberc-Dziedzic et al, 2010aOberc-Dziedzic and Kryza, 2012). South of the Strzelin Mas sif, the Variscan granitoids form the rel a tively large Žulová Pluton (c. 292 Ma, LA-ICP-MS U-Pb zir con age; Laurent et al, 2014).…”

The Late Carboniferous Schönfeld-Altenberg Depression on the NW margin of the Bohemian Massif (Germany/Czech Republic): volcanosedimentary and magmatic evolution

“…Interestingly, the isotopic fingerprint is also close to more distant PermoCarboniferous magmatic products such as Intra-Sudetic Basin volcanic rocks or the Žulová granite ( Fig. 12; Ulrych et al 2004;Laurent et al 2014).…”

“…11a), low TiO 2 , Zr and also Cr. Erzgebirge granites (Förster et al 2009;Förster and Romer 2010) Žulová granite (Laurent et al 2014) Intrasudetic basin volcanic rocks (Ulrych et al 2004) Rhyolites for four samples of -2.4 to -3.3 are significantly higher (i.e. more primitive) than Saxothuringian sediments (-7.0 to -11.6;Romer and Hahne 2010), and also unaltered rhyolites from comparable Halle Volcanic Complex of similar age (ε Nd = -6.7 to -7.0; Romer et al 2001).…”

A new computer program TecDIA for multidimensional tectonic discrimination of intermediate and acid magmas and its application to the Bohemian Massif, Czech Republic

“…1) in eastern part of the Variscan orogenic belt in Europe have been chosen to illustrate the application of TecDIA (see Žák J. et al 2014 for review). In the Bohemian Massif, the Late Devonian to Early Carboniferous Andeantype subduction-related setting led to an Early Carboniferous continental collision (Schulmann et al 2014;. The post-collisional activity included continental basin formation and late granitoid plutonism during Late Carboniferous-Early Permian (e.g.…”