Record details

Title
    Na-sanidine megacrysts from the Shavarin Caram volcano, Mongolia
Statement of responsibility
    Jaromír Ulrych, Edvín Pivec, Pavel Povondra, G. Buda
Author
    Buda, G.
    Pivec, Edvín
    Povondra, Pavel, 1924-
    Ulrych, Jaromír
Language
    anglicky
Source title - serial
    Acta mineralogica-petrographica
Vol./nr.
    Vol. 39
Pages
    p. 5-12
Year
    1998
Notes
    2 obr., 2 tab., 24 bibl.
    Zkr. název ser.: Acta mineral. petrogr. (Szeged)
Subject group
    alkalický typ
    brekcie vulkanická
    kenozoikum
    minerály horninotvorné
    petrogeneze
    sanidin
    tefrit
    vulkanismus
Geographical name
    Mongolsko
Keyword
    Caram
    Megacrysts
    Mongolia
    Na-sanidine
    Shavarin
    Volcano
Abstract (in english)
   Na-sanidine crystals, their fragment and corroded relics occur in scoria of leucite trachyte from the Shavarin Caram volcano, NW Mongolia, Opalescent perfect crystals of gem quality (up to 40 mm size) of moderate Or contents (46-49) reveal the following unit cell parameters: a=0.8334(9)nm, b=1.2997(6), c=0.7159(6), ß=16.17(5), V=0.6949(15) nm3. Na-sanidine together with garnet (Pyr-Alm), Al-clinopyroxene, Ti-phlogopite megacrysts represent a very strange, mostly high-pressure near-liquidus phenocryst association of high-potassic magma. Na-sanidine megacrysts, however, would crystallize probably from a Fe and fluid rich melt at lower pressure in near-solidus regions
Contributor
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
    U
Entered date
    21. 3. 2008
Import date
    8. 8. 2012