Record details

Title
    Ein metalateritisches Denudations-Niveau als lithologisch und zeitlich korrelierbarer Bezugshorizont in Phylliten, Glimerschieferen und Gneissen des ostbayerischen Grundgebirges
Statement of responsibility
    Hubert Mielka, Johann Rohrmüller, Dieter Gebauer
Other titles
    Geowissenschaftliche Untersuchungen im Umfeld der Kontinentalen Tiefbohrung (KTB), Oberpfalz (Variant.)
Author
    Gebauer, Dieter
    Mielka, Hubert
    Rohrmüller, Johann
Language
    německy
Source title - serial
    Geologica bavarica
Vol./nr.
    Jg. 101
Year
    1996
Notes
    9 obr., 5 fot., 3 tab., 4 s.bibl.
    Anglické resumé
    Zkr. název ser.: Geologica bavar.
Subject group
    alumosilikáty
    bauxit
    fylit
    lateritizace
    metamorfóza
    moldanubikum Českého lesa
    ordovik
    rula
    saxothuringikum
    svor
    zirkon
Geographical name
    ČR-Čechy
    Dyleň (Tachov)
    SRN-Bayern
Keyword
    Bezugshorizont
    Denudations-Niveau
    Glimerschieferen
    Gneissen
    Grundgebirges
    Korrelierbarer
    Lithologisch
    Metalateritisches
    Ostbayerischen
    Phylliten
    Zeitlich
Abstract (in english)
   Alumina- and manganese rich rocks within the Saxothuringian and Moldanubian zones of Eastern Bavarica can, based on their characteristic mineral parageneses, readily be traced as marker horizons. These meta-laterites are both conformably and unconformably bounded by pelitic, quartzitic and volcanic beds of low- to high metamorphic grade in the Fichtelgebirge (Saxothuringikum) and high-grade metamorphic rocks in the Oberpfälzer and the Passauer Wald (Moldanubicum). The present appearance of the meta-laterites is characterized by five different stages of metamorphic degrees. Common to all five stages is the metamorphic new growth of garnet, albite/oligoclase and alumina-silicate resulting in a significant coarsening of the grain-size. This facilitates the recognition of tectonic elements like folds and faults, that are otherwise difficult or impossible to map due to the lack of other suitable marker horizons in the country-rocks.
   Geochemically, the studied rocks are characterized, apart from their enrichment in Al and Mn, by elevated contents of Fe, Na, K and Ti (127 analyses). Ion probe (Shrimp) analyses carried out on zircons from the felsic metavolcanics that closely follow the marker horizon demonstrate Ordovician ages at ca. 470 Ma for both Saxothuringian and Moldanubian samples
Contributor
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
    U
Entered date
    14. 8. 2007
Import date
    8. 8. 2012