Podrobnosti záznamu

    Distances Between the Early/Middle Devonian Gondwana and Laurussia; Faunal and Spore Dispersals as Compared with Paleomagnetic Data on Paleolatitudes
Údaj o odpovědnosti
    Jindřich Hladil, Jiří Bek
    Bek, Jiří
    Hladil, Jindřich, 1953-
Zdrojový dokument - seriál
    Exploration, geophysics, remote sensing and environment
    Vol. 5, no. 2
    p. 29-33
    8 obr., 5 bibl.
    Zkr. název ser.: Explor. Geophys. remote Sens. Environm. (Brno)
Předmětová skupina
    Český masiv
    moravskoslezské prevariské paleozoikum
Geografické jméno
    Afrika severní
    Česká republika
Klíčové slovo
Abstrakt (anglicky)
   Reinvestigation of Early/Middle Devonian benthic faunas (namely corals) shows that the nothern and middle migration routes in the seas separating Gondwana and Laurussia were mostly oriented toward the southwest. The faunal domains involved cannot be grouped transversally. They must be regarded as finger-like canalized dispersions, which projected from their original sources in the Ural Ocean. However, the tectonically segmented relicts of Devonian sediments southwest of Prague yield a very typical Ibermaghian fauna, which documents a continuity between many peri-Gondwanan basins, e.g. in Algeria, Morocco, France (Montagne Noire, Armorican Massif), Spain (Cantabria) and Czechia (Barrandian). This "African" character of marine benthic fauna in the Barrandian strongly contrasts with abundance of plant spores connected to Ardenne/Rhenish/Moravian assemblages.
   These assemblages correspond to hot tropicals to subtropicals of southern latitudes and differ from both circumequatorial and cold temperate assemblages. It indicates a significant land barrier close to Laurussia, sharply limiting the transversal dispersal of the Ibermaghian marine organism toward the northwest and being responsible for massive overlap of the Ardenne/ Rhenish/ Moravian spores toward the south-sotheast. These faunal-floral relationships constrain any upper estimates of the Early/Middle Devonian distances between the north-Gondwanan and south-Laurussian margins where there is no place for several thousands of kilometers of oceans. The paleogeographic model with moderate transversal distances of several hundreds of kilometers corresponds to the paleomagnetically derived latitudes for the Early/Middle Devonian of the Barrandian and Moravian areas.
   These two areas differ in tectonic setting, but do not substantially differ in paleolatitudes, fluctuating within an interval of 10 to 20 degrees south
    Česká geologická služba
Kód přispěvatele
    ČGS (UNM)
Zdrojový formát
Datum vložení
    20. 8. 2007
Datum importu
    8. 8. 2012