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Behavior of trace elements in quartz from plutons of different geochemical signature: A case study from the Bohemian Massif, Czech Republic
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SYSNO ASEP 0392584 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Behavior of trace elements in quartz from plutons of different geochemical signature: A case study from the Bohemian Massif, Czech Republic Tvůrce(i) Breiter, Karel (GLU-S) RID, SAI, ORCID
Ackerman, Lukáš (GLU-S) RID, SAI, ORCID
Svojtka, Martin (GLU-S) SAI, RID, ORCID
Müller, A. (NO)Zdroj.dok. Lithos. - : Elsevier - ISSN 0024-4937
175/176, 15 August (2013), s. 54-67Poč.str. 14 s. Forma vydání Online - E Jazyk dok. eng - angličtina Země vyd. NL - Nizozemsko Klíč. slova Quartz ; trace elements ; granites ; fractionation ; Bohemian Massif Vědní obor RIV DD - Geochemie CEP GAP210/10/1105 GA ČR - Grantová agentura ČR Institucionální podpora GLU-S - RVO:67985831 UT WOS 000322430800005 EID SCOPUS 84878378159 DOI 10.1016/j.lithos.2013.04.023 Anotace The trace-element content in igneous quartz from granitoids of different geochemical types was investigated using the laser ablation ICP-MS technique. The Variscan granitoids in the Bohemian Massif provide an excellent opportunity to study the chemical composition of magmatic quartz from the following granite types: (1) geochemically primitive I-type tonalites and granodiorites, (2) peraluminous S-type two-mica granites, (3) moderately fractionated A-type volcano-plutonic complexes of the Teplice caldera, and (4) highly fractionated S- and A-type rare-metal granites. This diversity of granitoids permitted the study of the chemical composition of magmatic quartz as result of (i) different magma protoliths and (ii) variable degrees of differentiation. There were only small differences in the quartz trace-element contents, ranging from weakly to moderately differentiated plutons of all geochemical types: Al (mostly 20-250 ppm), Ti (mostly 20-110 ppm), B (<13 ppm), Be (<0.7 ppm), Ge (<1 ppm), Li (<30 ppm), and Rb (<2 ppm). Only the S-type granites from western Erzgebirge contain Al-enriched quartz (200-400 ppm Al) since the beginning of its evolution. However, quartz from the highly fractionated granites (group 4) differs significantly: it is poor in Ti (<20 ppm Ti) and enriched in Al (up to 600 ppm in A-type, and up to 1000 ppm in S-type granites), Be (up to 3.2 ppm), Ge (up to 5.7 ppm), Li (up to 132 ppm, particularly in the S-type granites), and Rb (up to 15 ppm). The input of Ti into quartz is controlled mainly by the temperature and pressure, the entry of Al into quartz increases as a function of the water and fluorine content of the residual melt. Ge and Li increase significantly with the fractionation of parental melt. Their concentrations are controlled by the order of crystallization of minerals: comb quartz crystallizing before Li-mica is strongly Li-enriched, whereas groundmass and snowball quartz crystallizing after mica is enriched in Ge. Pracoviště Geologický ústav Kontakt Jana Popelková, popelkova@gli.cas.cz, Sabina Janíčková, Tel.: 233 087 272 Rok sběru 2014
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