Podrobnosti záznamu

Název
    Causes of compositional diversity in a lobe of the Half Dome granodiorite, Tuolumne Batholith, Central Sierra Nevada, California
Autor
    Economos, Rita
    Erdmann, Saskia
    Memeti, Valbone
    Miller, Jonathan
    Paterson, Scott
    Žák, Jiří
Jazyk
    anglicky
Typ dokumentu
    článek v periodiku
Zdrojový dokument - seriál
    Earth and Environmental Science Transactions of the Royal Society of Edinburgh
Svazek/č.
    Roč. 100, č. spec. issue 1-2
Strany
    11
Rok
    2009
Výraz tezauru
    fractional crystallisation, magmatic processes, plutons
Klíčové slovo
    Batholith
    California
    Causes
    Central
    Compositional
    Diversity
    Dome
    Granodiorite
    Half
    Lobe
    Nevada
    Sierra
    Tuolumne
Abstrakt (anglicky)
   The causes of compositional diversity in the Tuolumne Batholith, whether source heterogeneity, magma mixing, or fractional crystallisation, is a matter of longstanding debate. This paper presents data from detailed mapping and a microstructural and major element, trace element and isotopic study of an elongate lobe of the Half Dome granodiorite that protrudes from the southern end of the batholith. The lobe is normally zoned from quartz diorite along the outer margin to high-silica leucogranite in the core. Contacts are steep and gradational, except for the central leucogranite contact, which is locally sharp: magmatic fabrics overprint contacts. A striking feature of the lobe is the 18 wt SiO2 range comparable to that observed for the entire Tuolumne Batholith. Feldspar-compatible elements (Sr and Ba) decrease towards the centre, while Rb increases. Light and middle REEs show a smooth decrease towards the centre of the lobe. Calculated initial isotopic ratios of 87Sr/86Sr(i) and
Přispěvatel
    Česká geologická služba
Kód přispěvatele
    ČGS (RIV)
Zdrojový formát
    R
Datum importu
    15. 10. 2014