A gutin-hegységi Firiza bazalt olvadékának „víz”-tartalma
Magmatic „water” content of Firiza basalt from the Gutin Mts.
Keywords:
FTIR, magmás H2O-tartalom, bazalt, NAM's, Avas-GutinAbstract
In this work we, studied the structural hydroxyl content of the Nominally Anhydrous Minerals (NAM's) found in the various dykes of the Firiza basalt in the Oas-Gutai Mts. with use of Fourier Transform Infrared (FTIR) spectrometry. To complement this method and understand what the measured hydroxyl contents mean, we also relied on petrographic observations, SEM-EDS and LA-ICP-MS analyses. Based on our results, it looks like that clinopyroxenes are able to retain their original „water” contents, therefore the H2O content of the basaltic magma in equilibrium with these phenocrysts can be estimated. The obtained „water” content (5.2 wt.%) falls in the range of arc magmas, which is in accordance with the assumed subduction related origin of the Oas-Gutai Mts. (Kovacs et al. 2017)
Kivonat
A munkánk során az Avas-Gutin hegységben található Firiza bazalt különböző teléreiből származó mintákban vizsgáltuk a névlegesen vízmentes ásványok (NAM's) fenokristályait Fourier-transzformációs infravörös (FTIR) spektrometria segítségével. Célunk az egyensúlyi magmás H2O-tartalom megbecslése és a kapott eredmény értelmezése. Ezért FTIR spektrometria mellett alkalmaztunk petrográfiai mikroszkópos, SEM-EDS és LA-ICP-MS vizsgálatokat is.
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