Lamprophyre-derived high-K mafic enclaves in Variscan granitoids from the Mecsek Mts. (South Hungary)
Buda, György; Dobosi, Gábor
published: Jul 9, 2004
ArtNo. ESP154018002002, Price: 29.00 €
Variscan magnesio-potassic microcline megacryst-bearing quartz monzonite and monzogranite contain several chromite-bearing high potassic mafic enclaves of various sizes in Mórágy Hills (South Hungary). These enclaves are biotite amphibol melamonzonite, amphibole biotite melasyenite and rarely amphibole meladiorite according to the classification of igneous rocks of the IUGS Subcommission on the Systematics of Igneous Rocks. The mineralogical, petrological and geochemical compositions of these basic enclaves correspond with lamprophyre-derived locally named vaugnerite/durbachite, which are widespread in the Variscan collision belt. The host plutonic rocks enriched in K and Mg due to the interaction of basic and acid magmas. The basic melt originated from the upper mantle revealed by the presence of chromite. The upper mantle was enriched in compatible and incompatible elements probable as a consequence of an older subduction. Acidic melt formed by the partial melting of the continental crust. Both melts crystallized simultaneously and affected each other. Mafic enclaves became more lamprophyric and the acidic one enriched in K and Mg. They formed probably in a postcollisional uplifted tectonic regime due to extension after compression.