Record details

Title
    Origin of felsic granulite microstructure by heterogeneous decomposition of alkali feldspar and extreme weakening of orogenic lower crust during the Variscan orogeny
Author
    Franěk, J.
    Haloda, J.
    Lexa, O.
    Schulmann, K.
    Štípská, P.
    Týcová, P.
    Ulrich, Stanislav
Language
    anglicky
Publication type
    článek v odborném periodiku
Source title - serial
    Journal of Metamorphic Geology
Vol./nr.
    Roč. 29, č. 1
Pages
    s. 103-130
Year
    2011
Notes
    Projekt: GA205/05/2187, GA ČR, CZ
    Projekt: GA205/09/0539, GA ČR3cav_un_auth*0252831
    Rozsah: 28 s.
    Výzkumný záměr: CEZ:AV0Z30120515
Subject category
    felsic granulites
    Moldanubian domain
    quantitative microstructural analysis
    quartz and feldspar rheology
    Variscan belt
Keyword
    Alkali
    Crust
    Decomposition
    During
    Extreme
    Feldspar
    Felsic
    Granulite
    Heterogeneous
    Lower
    Microstructure
    Origin
    Orogenic
    Orogeny
    Variscan
    Weakening
Abstract (in english)
   This study answers the question of origin and evolution of a granulitic microstructure typically developed in felsic granulites of the European Variscan belt. It shows that the precursor of the Variscan felsic granulites was a high-pressure alkali feldspar-rich coarse-grained layered orthogneiss. Its S1 subhorizontal layering is defined by the alignment of alkali feldspar porphyroclasts alternating with monomineralic bands of quartz and bands rich in plagioclase and garnet. The alkali feldspar porphyroclasts contain inclusions of quartz, garnet, kyanite, biotite and rutile, reflecting peak P-T conditions of 1.6-1.8 GPa and 850 °C during S1 formation.
Contributor
    AV ČR Brno, Geofyzikální ústav
Contributor code
    AV ČR, GFÚ
Source format
    U
Import date
    9. 12. 2013