Počet záznamů: 1  

Zircon and whole-rock Zr/Hf ratios as markers of the evolution of granitic magmas: Examples from the Teplice caldera (Czech Republic/Germany)

  1. 1.
    0477204 - GLU-S 2018 RIV AT eng J - Článek v odborném periodiku
    Breiter, Karel - Škoda, R.
    Zircon and whole-rock Zr/Hf ratios as markers of the evolution of granitic magmas: Examples from the Teplice caldera (Czech Republic/Germany).
    Mineralogy and Petrology. Roč. 111, č. 4 (2017), s. 435-457. ISSN 0930-0708
    Grant CEP: GA ČR GA14-13600S
    Institucionální podpora: RVO:67985831
    Klíčová slova: Zr/Hf value * zircon * Teplice caldera * rhyolite * rare-metal granite * Cínovec deposit
    Kód oboru RIV: DB - Geologie a mineralogie
    Obor OECD: Mineralogy
    Impakt faktor: 1.664, rok: 2017

    Hafnium contents and Zr/Hf ratios were studied in zircons and their parent rocks from three magmatic suites associated with the Teplice caldera, Eastern Erzgebirge: rhyolite and dacite from the peraluminous Schönfeld Unit, relatively younger A-type Teplice rhyolite, and post-caldera A-type biotite and zinnwaldite granite and greisen. New data suggest that zircon crystallizing from a geochemically less evolved volatile- and water-poor melt is, compared to the host rock, relatively Hf-depleted, while zircon crystallizing from an evolved volatile- and water-rich melt has a Zr/Hf value approximately identical to that of the parental melt. Zr/Hf values in zircon did not change substantially either during greisenization, or during low-temperature alteration after metamictization. Zr/Hf values in the whole rock may serve as a sensitive indicator of magmatic fractionation of evolved granitic melts, as they are only negligibly influenced by the following hydrothermal processes. Zr/Hf values in individual cogenetic zircon grains are scattered but their general evolution trend in the rock series is consistent with the evolution of the whole-rock Zr/Hf values.
    Trvalý link: http://hdl.handle.net/11104/0273578