Record details

    U-Pb zircon ages and structural development of metagranitoids of the Teplá crystalline complex: evidence for pervasive Cambrian plutonism within the Bohemian massif (Czech Republic)
Statement of responsibility
    Wolfgang Dörr, Jiří Fiala, Zdeněk Vejnar, Gernold Zulauf
    Dörr, Wolfgang
    Fiala, Jiří
    Vejnar, Zdeněk
    Zulauf, Gernold
Source title - serial
    Geologische Rundschau
    Vol. 87, no. 1
    p. 135-149
    8 obr., 1 fot., 2 tab., 2 s.bibl.
    Zkr. název ser.: Geol. Rdsch.
Subject group
    chemismus hornin
    Český masiv
    datování U/Pb
    tepelské krystalinikum
    vrásnění kadomské
Geographical name
    Dobrá Voda (Karlovy Vary)
    Lestkov (Tachov)
    Michalovy Hory (Tachov)
    Teplá (Karlovy Vary)
Abstract (in english)
   U-Pb zircon dating of three metagranitoids, situated within a tilted crustal section at the northwestern border of the Teplá Barrandian unit (Teplá crystalline complex, TCC), yield similar Cambrian ages. The U-Pb data of zircon of the Teplá orthogneiss define an upper intercept age of 513 +7/-6 Ma. The 207Pb/206Pb ages of 516 10 and 511 10 Ma of nearly concordant zircons of the Hanov orthogneiss and the Leskov granites are interpreted to be close to the formation age of the granitoid protolith. Similar to the Cambrian granitoids of the southwestern part of the Teplá Barrandian unit (Domažlice crystalline complex, DCC) the Middle Cambrian emplacement of the TCC granitoids postdates Cadomian deformation and metamorphism of the Upper Proterozoic country rocks, but predates Variscan tectonometamorphic imprints.
   Structural data as well as sedimentological criteria suggest a dextral transtensional setting during the Cambrian plutonism, related to the Early Paleozoic break-up of northern Gondwana. Due to strong Variscan crustal tilting, the degree of Variscan tectonometamorphic overprint is strikingly different in the dated granitoids. It is lowest in the weakly or undeformed Lestkov granite, located in the greenschist-facies domain. The Teplá orthogneiss in the north underwent pervasive top-to-NW mylonitic shearing under amphibolite-facies conditions. There is no indication for a resetting of the U-Pb isotopic system of the Teplá orthogneiss zircons that could be attributed to this imprint. Radiation damages accumulated until recent have probably caused lead loss
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
Entered date
    3. 1. 2008
Import date
    8. 8. 2012