Record details

Title
    Sm-Nd garnet ages and cooling history of high-temperature peridotite massifs and high-pressure granulites from lower Austria
Statement of responsibility
    Harry Becker
Author
    Becker, Harry
Language
    anglicky
Source title - serial
    Contributions to mineralogy and petrology
Vol./nr.
    Vol. 127, no. 3
Pages
    p. 224-236
Year
    1997
Notes
    9 obr., 1 tab., 2 s.bibl.
    Zkr. název ser.: Contr. Mineral. Petrology
Subject group
    datování Sm/Nd
    devon
    granáty
    granulit
    kolize desek
    metamorfóza
    moldanubikum
    moravikum
    peridotit
    podmínky P-T
    ultrabazika
    vrásnění variské
Geographical name
    ČR-Morava
    Rakousko-Niederösterreich
Keyword
    Ages
    Austria
    Cooling
    Garnet
    Granulites
    High-pressure
    High-temperature
    History
    Lower
    Massifs
    Peridotite
    Sm-Nd
Abstract (in english)
   High-temperature peridotites, garnet pyroxenites and associated granulites from Lower Austria (southern Bohemian Massif) yield Sm-Nd garnet ages (325-344 Ma), indicating Lower Carboniferous cooling and exhumation of the high-grade nappes during the Variscan orogeny. Ages of three samples are slightly older, most probably as a result of internal disequilibrium. Cooling rates estimated from thermochronology may have been between 25 and 150°C/Ma. Using the cooling rate estimates, closure temperatures for Nd tracer diffusion in garnets from peridotites and pyroxenites may have been in the range of 800-1000°C. The peridotite massifs most likely underwent near-isothermal decompression during extension in a late Devonian marginal basin. Closure of the basin in the lower Carboniferous and Crustal thickening resulted in metamorphism of high-pressure granulites and in shallow exhumation of the peridotites
Contributor
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
    U
Entered date
    21. 2. 2008
Import date
    8. 8. 2012