Új FTIR mérési eredmények az Avas–Gutin mészalkáli vulkáni kőzeteiből: poszterupciós hatások nyomai a fenokristályok szerkezeti hidroxil-tartalmában
New FTIR data from the Oaş–Gutâi Mts. and post eruption effects on the water content of phenocrysts
Keywords:
Avas-Gutin, Geokémia, Klinopiroxén, FTIRAbstract
We studied calc-alkaline volcanic rocks from the Oaş-Gutâi Mts.. The major goal of our research was the determination of ‘water’ content in the phenocrysts of the nominally anhydous minerals (NAMs) and also to uncover the possible post eruptive changes in the structural hydroxyl content of NAMs. The selected volcanic rocks were studied by petrography, EMPA, LA-ICP-MS, ICP-OES, ICP-MS and FTIR. Our assumption is that by studying the FTIR spectra of clinopyroxenes, the structural hydroxyl content of the NAMs changed in comparisons to the magmatic equilibrium.
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