Počet záznamů: 1  

Dynamics of Cambro–Ordovician rifting of the northern margin of Gondwana as revealed by the timing of subsidence and magmatism in rift-related basins

  1. 1.
    0576203 - GLÚ 2024 RIV GB eng J - Článek v odborném periodiku
    Žák, J. - Sláma, Jiří - Syahputra, R. - Nance, R. D.
    Dynamics of Cambro–Ordovician rifting of the northern margin of Gondwana as revealed by the timing of subsidence and magmatism in rift-related basins.
    International Geology Review. Roč. 65, č. 19 (2023), s. 3004-3027. ISSN 0020-6814. E-ISSN 1938-2839
    Institucionální podpora: RVO:67985831
    Klíčová slova: Avalonian–Cadomian belt * Bohemian Massif * hyperextension * passive margin * Rheic Ocean * laser ablation ICP-MS * U–Pb zircon geochronology * rifting
    Obor OECD: Geology
    Impakt faktor: 2.6, rok: 2022
    Způsob publikování: Omezený přístup
    https://www.tandfonline.com/doi/abs/10.1080/00206814.2023.2172619

    The Bohemian Massif of Central Europe is a Variscan collage of lithospheric fragments that formed at the northern margin of Gondwana during the late Neoproterozoic. A key geodynamic process that shaped this margin before it became involved in the Variscan orogen was the Cambro–Ordovician rifting that opened the Rheic Ocean. This rifting event has been studied extensively, yet a number of issues remain unresolved, among which are its geodynamic causes. New U–Pb zircon ages of orthogneisses from the mid-crustal Moldanubian unit, in combination with available information on magmatism and basin subsidence in the upper-crustal Teplá–Barrandian unit of the Bohemian Massif, are here used to reconstruct in detail the mechanism of the Cambro–Ordovician rifting. We argue that extension occurred in three phases defined by (1) protracted ~524–480 Ma intermediate to felsic plutonism (including the dated ~490–480 Ma orthogneisses), (2) basaltic submarine volcanism at ca. 470 Ma, and (3) rapid subsidence at ca. 458–452 Ma. This relative timing is interpreted to reflect stretching of the lower lithosphere before upper lithospheric rifting. In a broader context, these inferences are compatible with contrasting, rheologically controlled modes of northern Gondwana break-up during the early Ordovician, in which the westerly Avalonian-type terranes were rifted away from Gondwana, whereas the easterly Cadomian-type terranes formed a hyperextended Gondwanan shelf.
    Trvalý link: https://hdl.handle.net/11104/0345793

     
     
Počet záznamů: 1  

  Tyto stránky využívají soubory cookies, které usnadňují jejich prohlížení. Další informace o tom jak používáme cookies.