Record details

Title
    Lower Miocene Volcanoclastics in South Moravia and Lower Austria
Statement of responsibility
    Slavomír Nehyba, Reinhard Roetzel
Other titles
    Untermiozäne Vulkanoklastika in Südmähren und Niederösterreich
Author
    Nehyba, Slavomír
    Roetzel, Reinhard
Language
    anglicky
Source title - serial
    Jahrbuch der Geologischen Bundesanstalt
Vol./nr.
    Vol. 141, no. 4
Pages
    p. 473-490
Year
    1998
Notes
    15 obr., 1 fot., 3 tab., 4 s.bibl.
    Německé resumé
    Zkr. název ser.: Jb. Geol. Bundesanst. (Wien)
Subject group
    dacit
    fission tracks
    granulometrie
    karpatská neogenní předhlubeň
    korelace stratigrafická
    miocén-spodní
    ryolit
    sklo vulkanické
    vulkanoklastika
    zirkon
Geographical name
    ČR-Morava
    Ivančice (Brno-venkov)
    Miroslav (Znojmo)
    Plaveč (Znojmo)
    Rakousko-Niederösterreich
    Strachotice (Znojmo)
    Únanov (Znojmo)
    Višňová (Znojmo)
    Znojmo
    Žerotice (Znojmo)
Keyword
    Austria
    Lower
    Miocene
    Moravia
    South
    Volcanoclastics
Abstract (in english)
   The Lower Miocene volcaniclastics from the Carpathian Foredeep in South Moravia and the Molasse Zone of Lower Austria have an acidic character (rhyodacites). The source of volcanic material was from a calc-alkaline volcanic suite of a volcanic arc. The estimated eruption temperature lies between 720°C and 780°C. Tephra was produced by the Neogene aerial type of dacite and rhyolite volcanic activity in the Carpatho-Pannonian region. The volcanic source is probably located in Northern Hungary and Eastern Slovakia. Studied volcaniclastics belong to the distal tallout tephra. Postdepositional processes partly highly influenced composition, texture and structure of the volcaniclastics. Based on zircon studies two horizons of volcaniclastics (horizon I and II) have been recognized. The existence of different horizons is explained by several eruptional phaes in the same source area and a stratified magmatic chamber. The lower horizon (horizon I) is Upper Eggenburgian in age.
   Its average absolute age (Fission-track-dating) is 20.3 2.4 Ma. The upper horizon (horizon II) can be correlated with tephra layers of the Zellerndorf Formation and Langau Formation (Molasse Zoe of Austria). These rocks are Ottnangian in age. Volcaniclasitcs from the locality Herrnbaumgarten (Vienna Basin) which were formerly assumed to correlate with the above mentioned tephra layers show different characteristics of volcanic zircons. For that reason a different source is most probable
Contributor
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
    U
Entered date
    25. 3. 2008
Import date
    8. 8. 2012