Record details

Title
    Chemical changes in Moldanubian amphibolites caused by regional metamorphism
Statement of responsibility
    Dušan Němec
Author
    Němec, Dušan, 1927-2001
Other author; role
   Suk, Miloš
   Původce
Language
    anglicky
Source title - serial
    Krystalinikum
Vol./nr.
    Vol. 25
Pages
    p. 105-125
Year
    1999
Notes
    16 obr., 4 tab., 3 s.bibl.
    České resumé
    Zkr. název ser.: Krystalinikum
Subject group
    amfibolit
    chemismus hornin
    metagabro
    metamorfóza regionální
    metavulkanity
    migmatitizace
    migrace prvků
    moldanubikum
    vrásnění variské
Geographical name
    ČR
Keyword
    Amphibolites
    Caused
    Changes
    Chemical
    Metamorphism
    Moldanubian
    Regional
Abstract (in english)
   The regionally metamorphosed Moldanubian rocks of the Bohemian-Moravian Plateau (Českomoravská vrchovina) represent a polymetamorphic complex was mostly metamorphosed to the highest grades of the amphibolite facies. It largely consists of various types of gneisses which often contain bodies of orthoamphibolites. Conspicuous chemical changes occurred in them during regional metamorphism. It can be shown that these changes were not caused by spilitization or by another type of premetamorphic alteration. The chemical changes were studied by two approaches. The chemical composition of relict gabbros, which are exceptionally preserved in a few amphibolite complexes, was compared with the composition of concentrations of elements contained in the amphibolites, which are known to be mobile and immobile, respectively, during regional metamorphism. Regional metamorphism caused an increase in abundance of LILE, particularly of K, Rb, Ba and Th.
   Apparently, this input of LILE came from gneisses which envelope the amphibolite bodies during their Variscan migmatization
Contributor
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
    U
Entered date
    28. 3. 2008
Import date
    8. 8. 2012