Record details

Title
    40Ar/39Ar isotopic evidence for mid-Devonian post-metamorphic pegmatite emplacement in the Mariánské Lázně Complex, Bohemian Massif, Central European Hercynides
Statement of responsibility
    Donald R. Bowes, Van Breemen, A.M. Hopgood, Emil Jelínek
Author
    Bowes, Donald R.
    Hopgood, A. M.
    Jelínek, Emil, 1943-
    Van Breemen, O.
Language
    anglicky
Source title - serial
    Neues Jahrbuch für Mineralogie. Monatshefte
Vol./nr.
    H. 10
Pages
    s. 445-457
Year
    2002
Notes
    2 obr., 1 tab., 3 s.bibl.
    il.
    Zkr. název ser.: Neu. Jb. Mineral., Mh.
Subject group
    amfibolit
    amfiboly
    dajka
    datování Ar/Ar
    devon-střední
    mariánskolázeňský bazický komplex
    pegmatit
    vmístění
    vrásnění variské
Geographical name
    ČR-Čechy
    Tisová (Karlovy Vary)
Keyword
    40Ar/39Ar
    Bohemian
    Central
    Complex
    Emplacement
    European
    Evidence
    Hercynides
    Isotopic
    Lázně
    Mariánské
    Massif
    Mid-Devonian
    Pegmatite
    Post-metamorphic
Abstract (in english)
   Large (2-3 cm) crystals of ferroan pargasite in a narrow pegmatite vein that cross-cuts amphibolite in the Mariánské Lázně Complex yield 40Ar/39Ar regression ages of 378.7+-3.5 and 379.5+-4.3 Ma: these date the time of cooling through 550-500 °C soon after emplacement and crystallization. With this and associated veins also cutting flexural-type folds and a fracture cleavage, both tectonothermal activity in, and uplift of the host metamorphic assemblage into the upper crust must have taken place by, or near, a time corresponding to the Eifelian-Givetian boundary (mid-Devonian). The age of pegmatite formation corresponds, within errors, with the time of closure of the Sm-Nd isotopic system in eclogites elsewhere in the domain (377+-7 Ma). This points to the crustal uplift having been rapis.
   Isotopic evidence also indicates a considerable time gap between the tectonothermal - igneous activity so prominently expressed in the Mariánské Lázně Complex and the superimposed effects of early Carboniferous tectonothermal activity
Contributor
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
    U
Entered date
    12. 9. 2007
Import date
    8. 8. 2012