Podrobnosti záznamu

Název
    Ocean floor basalt, not continental gabbro: a reinterpretation of the Hoher Bogen amphibolites, Teplá-Barrandian, Bohemian massif
Údaj o odpovědnosti
    G. Propach, T. Pfeiffer
Autor
    Pfeiffer, T.
    Propach, G.
Jazyk
    anglicky
Zdrojový dokument - seriál
    Geologische Rundschau
Svazek/č.
    Vol. 87, no. 3
Strany
    p. 303-313
Rok
    1998
Poznámky
    6 obr., 1 fot., 3 tab., 2 s.bibl.
    Zkr. název ser.: Geol. Rdsch.
Předmětová skupina
    amfibolit
    Barrandien
    bazalt typu MORB
    chemismus hornin
    gabro
    kambrium
    kůra oceánská
    mariánskolázeňský bazický komplex
    metamorfóza
    moldanubikum
    proterozoikum
    vrásnění variské
Geografické jméno
    ČR-Čechy
    SRN-Bayern
Klíčové slovo
    Amphibolites
    Basalt
    Bogen
    Bohemian
    Continental
    Floor
    Gabbro
    Hoher
    Massif
    Ocean
    Reinterpretation
    Teplá-Barrandian
Abstrakt (anglicky)
   At its southern margin along the hoher Bogen mountain, the Teplá-Barrandian (Bohemian massif, Central Europe) is made up of a 1- to 4-km wide belt of amphibolites. An upper amphibolites/lower granulite facies Variscan metamorphism has brought forth coarse-grained, weakly foliated rocks with hbl+pl+cpx+opx+grt parageneses. Since the begining of this century, these rocks, together with fine-grained or mylonitized amphibolites, have been regarded as metamorphic gabbros (gabbro amphibolites) of the Neukirchen-Kdyne igneous complex. Relics of magmatic textures, however, cannot be found anywhere. The amphibolites are therefore reinterpreted as metamorphic basalt. The Hoher Bogen amphibolites (HBA) derive from N-type MORB. The most primitive samples have Mg=s between 60 and 65. Locally occurring (garnet-) hornblendites and leucodiorites mobilisates are the products of partial melting of amphibolites during the Variscan metamorphism and do not belong to the primary magmatic rock association.
   Ultramafic rocks are tectonically emplaced between the HBA belt and the metampelitic rocks of the Moldanubian. At the very least, the metapyroxenites among them seem to have a cumulus origin. Together with the ultramafic rocks, the HBA belt may be regarded as a metaophiolite, comparable to the Mariánské Lázně complex. The reinterpretation of the the former "gabbro amphibolites" as a metaophiolite has consequences for the geology of the Teplá-Barrandian: the size of the Neukirchen-Kdyne igneous complex is reduced. The HBA belt is a piece of oceanic crust which is possibly younger than the Precambrian metasedimentary/metavolcanic country rock of the Neukirchen-Kdyne igneous complex
Přispěvatel
    Česká geologická služba
Kód přispěvatele
    ČGS (UNM)
Zdrojový formát
    U
Datum vložení
    3. 1. 2008
Datum importu
    8. 8. 2012