Original scientific paper

METARHYOLITES OF VRANICA MOUNTAIN IN PALEOZOIC OF CENTRAL BOSNIA

Vladimir Majer
Vesnica Garašić

Abstract

Metharyolites of Vranica mountain are roks of emphasized porphyritic texture containing phenocrysts of quartz, K.feldspar and very rarely albite. The groundmass is microcrystallinic, characterized by finegrained phengite, biotite and area consisting of granophyric intergrowths of quartz and feldspar. Accessory minerals are ilmenite, rutila, apatite, zircon and chlorite. Metarhyolites are peraulminous rocks (PI=1.-4.1) having dominantly potassium character (K2O/Na2O=1,3-13,8). Incompatible elements are enriched relative to the normalizing chondrite composition, pointing to the crustal origin of metarhyolite magma. Although phengites typically occur in high pressure rocks, it seems that phengites of metarhyolites of Vranica mountain belong to the seldom group of phengites occurring in the low to medium pressure rocks.

Keywords

Metarhyolites; Peraaluminous rocks; Granophyric texture; Phengites

Hrčak ID:

13411

URI

https://hrcak.srce.hr/13411

Publication date:

4.12.2001.

Article data in other languages: croatian

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