Granodioriti Stražanice na zadadnim padinama Cera (Zapadna Srbija)

Granodiorites of Stražanica on the western slopes of Cer Mt. (Western Serbia)

Abstract

The Stražanica intrusion represents a homogeneous granodioritic mass, intruded along a large fault into Permocambrian argilophyllite and sandstones of the Jadar facies. The most important minerals are quartz, plagioclase, biotite and K feldspar with zircon, apatite, magmatic epidote, orthite and sphene. K feldspar is represented by microcline with 6.4 to 9.2 % Ab. Plagioclase is abundant constituent. Tlh cores of coarser zonal crystals are andesinic, but their rims and finer grains correspond to oligoclase. Biotite belongs to the group which does not exist with other coloured minerals displaying metaniorphic character, too. According to geochemical data, the Stražanica granodiorite belongs to I type magmatite contaminated by crustal material. The age of crustal assimilate is about 0.85 Ga. The degree of contamination, determined by Sr isotopes and ɛNd is temperate weaker than contamination of the Cer and Boranja gianodioritic massif. The Stražanica granodiorite is Miocene, 19-17 Ma.; the lowest age (about 17 m.y.) show only biotites that are the oldest, but reheated by intruding of Cer leucogranite. Geochemical composition indicates the rocks originated during precollisional condition and have a distinctive volcanic arc affinity

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