SOME REE-BEARING ACCESSORY MINERALS IN TWO TYPES OF VARISCAN GRANITOIDS, HUNGARY

Year, pages: 1995, 67 - 78

The two main types of Hungarian Variscan granitoids are different in many respects. The older one, occurring in South Hungary (Mecsek Mts.), is syncollision S-, I-type, migmatitic with a monzonitic suite. The rocks are enriched in REE with abundant REE-bearing accessory minerals such as allanite, zircon, apatite, thorite, monazite, titanite and secondary rare earth fluorcarbonates. The REE distribution pattern of the whole rock is strongly influenced by the composition of allanite which is the most common REE-rich mineral. Later hydrothermal alteration caused depletion of Ce, Th etc., from allanite and resulted in crystallization of secondary rare earth fluorcarbonates and thorite. The different REE contents of zircon and apatite crystal cores suggest variable source rocks. The younger postcollision Variscan granitoids (along the Velence-Balaton tectonic line) are intrusive S- or A-type with a granodioritic suite. The granitoids as well as their allanites are relatively enriched in HREE+Y, due to flux of a volatile enriched solution at the end of crystallization but the SREE content is low.

Buda, G., Nagy, G. 1995. SOME REE-BEARING ACCESSORY MINERALS IN TWO TYPES OF VARISCAN GRANITOIDS, HUNGARY. In Geologica Carpathica, vol. 46, no.2, pp. 67-78. 1335-0552.

Buda, G., Nagy, G. (1995). SOME REE-BEARING ACCESSORY MINERALS IN TWO TYPES OF VARISCAN GRANITOIDS, HUNGARY. Geologica Carpathica, 46(2), 67-78. 1335-0552.