Record details

    Mafic K- and Mg-rich magmatic rocks from Western Mühlviertel (Austria) area and the adjacent part of the Šumava Mountains (Czech Republic)
    Breiter, Karel
    Koller, Friedrich
Publication type
    článek v periodiku
Source title - serial
    Jahrbuch der Geologischen Bundesanstalt
    Roč. 149, č. 4
Thesaurus term
    granitoid,durbachite,glimerite,Bohemian Massif,Moldanubicum,Upper Austria,Czech Republic
Abstract (in english)
   One large and several small bodies of typical durbachite (SiO2 around 60-65%) appear in the Czech territory to the north of the Vltava valley. Several smaller bodies of extreme basic and mafic varieties of durbachite were newly found on both the Czech and Austrian sides of the state border, N of the town of Schwarzenberg: pyroxene-phlogopite melasyenite (<50% SiO2) and amphibole-phlogopite melasyenite (50-55% SiO2). Both varieties contain phenocrysts of K-feldspar (Kfs, about 3x1 cm) in a matrix of oligoclase, phlogopite (xMg=0.58-0.67), and actinolite (xMg=0.67-0.80), occasionally also diopside (xMg=0.74-0.78). Several ultramafic dykes with a content of mafic minerals >90% appear in the endo- and exocontact of the Prachatice and Křišťanov granulite bodies. The dyke rocks, termed here as glimmerites, are medium- to fine-grained, composed mainly of phlogopite (xMg 0.65-0.80) and actinolite (xMg=0.75-0.85). Cummingtonite (xMg=0.70-0.75) or diopside (xMg=0.81-0.83) appears only locally
    Česká geologická služba
Contributor code
    ČGS (RIV)
Source format
Import date
    15. 10. 2014