Podrobnosti záznamu

    Detrital zircon populations in quartzites of the Krkonoše-Jizera Massif - implications for pre-collisional history of the Saxothuringian Domain in the Bohemian Massif
    Jeřábek, Petr
    Konopásek, Jiří
    Košler, Jan
    Žáčková, Eliška
Typ dokumentu
    článek v periodiku
Zdrojový dokument - seriál
    Geological Magazine
    Roč. 149, č. 3
Výraz tezauru
    detrital zircon, laser ablation ICP-MS, Saxothuringian Domain, Bohemian Massif
Klíčové slovo
Abstrakt (anglicky)
   Age spectra of detrital zircons from metamorphosed quartzites of the Krkonoše-Jizera Massif in the northeastern part of the Saxothuringian Domain were obtained by U-Pb laser ablation inductively coupled plasma mass spectrometry dating. The zircon ages cluster in the intervals of 450-530 Ma and 550-670 Ma, and show individual data between 1.6 and 3.1 Ga. Zircons in the analysed samples are predominantly of Cambrian-Ordovician and Neoproterozoic age, and the marked peak at c. 525-500 Ma suggests a Late Cambrian maximum age of the sedimentary protolith. Detritus of the quartzites probably originated from the erosion of Cambrian-Ordovician granitoids and their Neoproterozoic (meta)sedimentary or magmatic country rocks. The lack of Neoproterozoic (meta)sedimentary rocks in the central and eastern part of the Krkonoše-Jizera Massif suggests that the country rocks to voluminous Cambrian-Ordovician magmatic bodies were largely eroded during the formation of Early Palaeozoic rift basins along t
   he south-east passive margin of the Saxothuringian Domain. The detrital zircon age spectra confirm the previous interpretation that the exposed basement, dominated by Neoproterozoic - Cambrian-Ordovician granitoids was overthrust during Devonian-Carboniferous subduction-collision process by nappes composed of metamorphosed equivalents of the uppermost Cambrian-Devonian passive margin sedimentary formations. Only a negligible number of Mesoproterozoic ages, typically from the Grenvillian event, supports the interpretation that the Saxothuringian Neoproterozoic basement has an affinity to the West African Craton of the north-western margin of Gondwana.
    Česká geologická služba
Kód přispěvatele
    ČGS (RIV)
Zdrojový formát
Datum importu
    15. 10. 2014