PETROLOGY OF 2 GRANITE TYPES FROM THE TRIBEC MOUNTAINS, WESTERN CARPATHIANS - AN EXAMPLE OF ALLANITE (+ MAGNETITE) VERSUS MONAZITE DICHOTOMY

Two granitoid series have been distinguished in the Tribec Mountains ( Western Carpathians) on the basis of the contrasting petrological beha viour of their accessory minerals. The allanite-magnetite-bearing (AM) tonalite-granodiorite-granite series typically contains dark magmatic enclaves and is produced from oxidizing, more hydrous (about 5.2 wt.% water) melts that were emplaced at depths equivalent to 350 +/- 100 M Pa. The monazite-bearing (M) tonalite-granodiorite-granite series cont ains only metamorphic xenoliths and comes from reduced and drier (abou t 2.3 wt.% water) melts that were probably emplaced at a shallower dep th. The inferred magma properties probably reflect source rock effects . The mineralogical discrimination scheme between the AM and M series corresponds broadly to I- and S-type subdivision and may be useful not only for the granitoid bodies in the Western Carpathians but also for the whole Variscan orogenic belt.