Record details

    Does ternary feldspar constrain the metamorphic conditions of high-grade meta-igneous rocks? Evidence from orthopyroxene granulites, Bohemian Massif
Other titles
    viz název v původním jazyce
    Powell, Roger
Publication type
    článek v periodiku
Source title - serial
    Journal of Metamorphic Geology
    Roč. 23, č. 8
Thesaurus term
    Bohemian Massif, garnet zoning, orthopyroxene granulite, ternary feldspar, UHT metamorphism
Abstract (in czech)
   viz popis výsledku v původním jazyce
Abstract (in english)
   The presence of ternary feldspar in high-grade meta-igneous rocks, and the recognition of the thermometric significance of this mineral, has led recent researchers to postulate peak metamorphic temperatures in excess of 1000 degrees C. However, it needs to be established that such ternary feldspar is not in fact a survivor of the original high-temperature crystallization of the igneous protolith. After exsolution, the host and lamellae in the ternary feldspar grains may be stable throughout subsequent history as long as recrystallization does not occur. Such a history may involve rehydration and metamorphism, including H2O-saturated conditions, with the compositions and proportions of the host and lamellae being modified to reflect the P-T conditions experienced. In the case of the high-grade meta-igneous rocks from the Moldanubian of the Bohemian Massif, some samples that contain ternary feldspar preserve a substantial measure of their igneous heritage.
    Česká geologická služba
Contributor code
    ČGS (RIV)
Source format
Import date
    15. 10. 2014