Podrobnosti záznamu

Název
    Epithermal tertiary Pb-Zn-Cu (Ag, Te) mineralization in the Roztoky Volcanic Centre, České středohoří Mts., Czech Republic
Údaj o odpovědnosti
    Edvín Pivec, Jaromír Ulrych, Vladimír Šrein, Jiří Bendl, Petr Dobeš, Karel Žák
Autor
    Bendl, Jiří
    Dobeš, Petr
    Pivec, Edvín
    Šrein, Vladimír
    Ulrych, Jaromír
    Žák, Karel, 1957-
Jazyk
    anglicky
Zdrojový dokument - seriál
    Geologica carpathica
Svazek/č.
    Vol. 49, no. 2
Strany
    p. 139-146
Rok
    1998
Poznámky
    4 obr., 2 tab., 2 s.bibl.
    Zkr. název ser.: Geol. carpath.
Předmětová skupina
    alkalický typ
    diorit
    geneze ložiska
    geochemie izotopická
    inkluze fluidní
    karbonáty
    lamprofyry
    ložisko epitermální
    rudy barevných kovů
    sulfidy
    vulkanity Českého středohoří
Geografické jméno
    ČR-Čechy
    Roztoky (Ústí nad Labem)
Klíčové slovo
    Ag
    Centre
    Czech
    České
    Epithermal
    Mineralization
    Mts
    Pb-Zn-Cu
    Republic
    Roztoky
    Středohoří
    Tertiary
    Volcanic
Abstrakt (anglicky)
   The abandoned Roztoky silver-base metal deposits represents ascarce example of Tertiary sulphide veintype mineralization spatially and genetically associated with intraplate volcanic rocks of the Cenozoic West and Central European Volcanic Province. The deposit is situated in the Tertiary Roztoky Volcanic Centre (RVC) of the České středohoří Mts., within the Ohře (Eger) Rift. The main ore vein parallels an older bostonite dyke intersecting the monzodiorite body, however, both are intersected by a younger trachyte dike. This suggests that the origin of the mineralization is related to the development of the RVC. The 13C values of vein carbonates indicate: the influence of deep-seated CO2 but the O isotopic composition of hydrothermal fluids (calculated 18O fluid values from -3 to -7 %. SMOW) shows the dominance of water with relatively shallow circulation.
   Sphalerite-galena sulphur isotopic geothermometry yielded temperatures between 200 and 250°C and the presence of cubic hessite indicates temperatures above 155°C. The calculated 34S fluid values vary in the range -1.0 to -2.0%.. The presence of banded "colloform" sphalerite and chalcedony suggests lower temperatures. High lead isotope ratios of galena (206 Pb/204 Pb about 19.03,207 Pb/204 Pb about 15.67, 208 Pb/204 Pb about 39.17) can be a result of mobilization of lead either from Tertiary magmatic rocks, which show similar lead isotope ratios and were probably derived from a sublithospheric HIMU mantle source, or from upper-crustal rocks, e.g. local Upper Cretaceous sediments. The 87Sr/86Sr isotope ratios of the principal hydrothermal carbonates rhodochrosite (0.70524) and calcite-dolomite (0.70510) are higher than both the local primitive magma derivatives and even the developed rocks of the RVC and indicate an admixture of Sr derived from local crustal rocks.
   The volcanic rocks of the RVC were dominant heat source during the formation of the ore deposit. The hydrothermal deposit was formed during relatively shallow hydrothermal circulation of low to medium salinity, low - 18O fluids supported by CO2 influx of deep-seated origin
Přispěvatel
    Česká geologická služba
Kód přispěvatele
    ČGS (UNM)
Zdrojový formát
    U
Datum vložení
    18. 2. 2008
Datum importu
    8. 8. 2012