Search

2 ABSTRACT. The Romanian territory contains numerous ore deposits mined since pre-Roman times. An assessment of historical gold production of the Gold Quadri- lateral (GQ) yielded a total estimate of 55.7 Moz of gold throughout an area of 2400 km 2 . Interpreted in terms of mineralization density this is 23,208 oz of gold/ km 2 . The geological setting of the GQ is represented mainly by Tertiary (14.7 My to 7.4 My) calc-alkaline volcano-plutonic complexes of intermediate character in sedimentary basins of molasse type. These basins are tectonically controlled by NW-SE lineation across early Alpine magmatic products, i.e. subduction related Jurassic-Lower Cretaceous igneous association (island arc ophiolites and granitoids) and Upper Cretaceous igneous association (banatites). The Tertiary magmatism is associated with extensional tectonics caused by NE escape of the Pannonian region during Upper Oligocene-Lower Miocene times. As a result of tectono-magmatic and mineralization-alteration characteristics, two metallogenetical types were separated in the GQ, i.e. calc-alkaline andesitic (CAM) and sub-alkaline rhyodacitic (SRM). Both develop almost entirely low-sulfidation type of Au epithermal mineralization. However, two subtypes, -rich in sulfide (2-7%) and -poor in sulfide (7-20%) were delineated and correlated with CAM type and SRM type respectively. Furthermore, CAM is connected at deeper levels with Cu-Au+/-Mo porphyry systems in contrast with SRM, which is a non-porphyry environment. The Brad-Sacarâmb district contains mainly CAM type andesitic structures. It is a porphyry environment with epithermal low-sulfidation-rich sulfide vein halo (Barza, Troiţa-Bolcana deposits). However, a few SRM type patterns, such as Magura Ţebii, Baiţa-Craciunesti and Sacarâmb, deposits exhibit Au-Ag-Te low-sulfidation-poor sulfide epithermal vein halo. The Zlatna-Stanija district exhibits similar characteristics, with Au-Ag+/-Pb, Zn veins in Cu-Au subvolcanic-porphyry environment (CAM type). An exception is the Faţa Baii Au-Ag-Te vein system that corresponds to SRM type. Rosia Montana-Bucium district is more elaborated in terms of a porphyry- epithermal relationship. Both CAM type (Rosia Poieni, Bucium Tarniţa deposits) and SRM type (Rosia Montana deposit) exist. The Baia de Aries district is definitely the non-porphyry environment of SRM type, with Au-Ag-Te veins and breccia pipes hosted in sub-alkaline andesitic rocks.

2 ABSTRACT. The Romanian Carpathians sector of the Late Cretaceous Banatitic Magmatic and Metallogenetic belt (BMMB) contains 1) plutons and volcano-plutonic complexes, i. e. calc-alkaline, I-type granitoids, with related ores; 2) shoshonitic plutons that lack economic interest. Two provinces have been delineated: the Apuseni Mts. Province in the North and the Western South Carpathians in the South. Apuseni Mts. Province is a non-porphyry environment related to more evolved (granodioritic-granitic) magmatism. It is subdivided into three zones: Vladeasa (Pb-Zn ores of restricted metallogenetic potential); Gilau-Bihor (Fe, Bi, Mo, Cu, W, Au, Ni, Co, Pb, Zn, Ag, U, B ores / conspicuous peri-batholitic arrangement) and South Apuseni (only one minor Fe-skarn occurrence). Western South Carpathians Province occurs in Romania and extends in Eastern Serbia. It is subdivided into South Banat Mts.-Timok Zone (SBTZ) and Poiana Rusca Mts.- North Banat Mts.- Ridanj-Krepoljin Zone (PR-NB-RKZ). SBTZ is a typical porphyry environment of high metallogenetic potential (Cu, Au, Pb, Zn), while PR- NB-RKZ is a non-porphyry environment with small to medium size Pb, Zn, Fe, Cu deposits/prospects exhibiting commonly a peri-plutonic zoning. The metallogenetic model of the Romanian Carpathians segment of BMMB is conceived based on correlating magma composition/level of emplacement and ore types.