THE UPPER CRETACEOUS BANATITIC MAGMATIC AND METALLOGENETIC BELT IN THE ALPINE CARPATHIAN-BALKAN CHAIN OF EUROPE

An elongated Upper Cretaceous igneous belt with related ore deposits – the Banatitic Magmatic-Metallogenetic Belt (BMMB) – runs discontinuously in SE Europe from the Apuseni Mountains through the South Carpathians (Banat Mts and Timok Massif) to Srednogorie. This association stems from von Cotta (1864) who named intrusions in Banat and Timok as “Banatites”. BMMB includes volcanic/plutonic rocks in elongated grabens, and adjacent plutons and dykes. Geotectonic models suggest either northward subduction of the Vardar/Thetys Ocean during Jurassic-Lower Cretaceous, or north-westward subduction of the Severin Ocean (adjacent to the main Thetys trench). An alternative interpretation – post subduction/post collisional extensional setting – challenges the “classic” subduction models. Petrogeochemical data reveal four magmatic trends: tholeiitic, calc-alkaline, calc-alkaline high K to shoshonitic and peralkaline. I-type /magnetite-series granitoids prevail. The source is deep crustal or upper mantle, with upper crust contamination. Calc-alkaline hydrated magmas are related to: more primitive, monzodioritic, dioritic to granodioritic trend; more evolved, granodioritic to granitic trend;alkaline trend. The metallogenetic model of BMMB is based on correlating magma composition/level of emplacement and ore typology. It contains: non-porphyry environment, with granodioritic to granitic magmas, plutonic level, prevalence of skarn deposits; porphyry environment with monzodioritic or dioritic to granodioritic magmas, subvolcanic-hypabyssal- plutonic level and porphyry copper – skarn halo; porphyry environment with monzodioritic or dioritic to granodioritic magmas, volcano-plutonic complexes with porphyry copper and high sulfidation epithermal/massive sulfides at subvolcanic-volcanic level; non-porphyry environment with magmas of alkaline tendency, volcanic level, veins. BMMB as a part of the sub-global Tethyan-Eurasian unit exhibits similarities with the Cordilleran –Andean megaunit, especially to the Arizona-New Mexico portion. Famous ore-bearing settings and type –locality occurrences for rare minerals in Romanian skarn and vein deposits are presented.