Naslov
Ore-forming fluids associated with Pb-Zn-Ag-sulfide mineralisation of Rogozna and South Kopaonik mineral belt

Autori
Sabina Strmić Palinkaš, Sibila Borojević Šoštarić, Milica Veselinović Williams, Vladica Cvetković, Ladislav Palinkaš, Andy Rankin, Peter Treloar

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Advanced in Regional Geological and Metallogenic Studies in Carpathians, Balkans, Rhodope Massif and Caucauses (Romania, Serbia, Bulgaria and Georgia). / Robert Moritz and Albrecht von Quadt - Beograd, 2007

Skup
Advanced in Regional Geological and Metallogenic Studies in Carpathians, Balkans, Rhodope Massif and Caucauses (Romania, Serbia, Bulgaria and Georgia).

Mjesto i datum
Beograd, Srbija, 04.09.2007. - 07.09.2007

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Pb-Zn-Ag deposits; fluid inclusions; Kopaonik; Neogene volcanism

Sažetak
Rogozna and Kopaonik Mts. are a part of the Western Vardar zone (WVZ), situated between Drina-Ivanjica blok on the West and Kopaonik Ridge on the East. The WVZ is composed mainly of the Jurassic ophiolite complex (serpentinite, gabbro, pillow lavas and amphibolites), placed within a mélange formation. It is sporadically cross-cut by the Tertiary volcanics. Volcanic rocks in the area are represented by the Oligocene-Miocene, dominantly basalt-andesites and, latites, q-latites and associated pyroclastites. The Neogene syncollisional volcanism produced numerous Pb-Zn-Ag mineral deposits which extend northward from Kosovo and southern Serbia (Trepča, Belo Brdo, Crnac) along the Kopaonik ridge. The metallogenic district hosts skarns, hydrothermal replacements and vein type deposits. The on-going studies, on Trepča, Belo Brdo and Crnac mines, is focused on the P-T-X formation conditions and refinement of genetic models in order to improve exploration on similar deposits in the region. The Trepča mine: Mineralisation is hosted by limestones with developed paleokarst, covered by Triassic schists. Ore forming process is related to the phreatomagmatic event (maar type). Commonly skarn minerals (ilvaite, hedenbergite, garnet) precede sulfide mineralisation. Fluid inclusions (FIs) studies were carried out on skarn (hedenbergite: Th=385-410°C, 14.8-16.5 wt.% NaCl equ.), sulfide (sphalerite: Th=240-305°C, 8.0-14.6 wt.% NaCl equ.) and gangue minerals (quartz: Th=295-355°C, 4.5-12.0 wt.% NaCl equ. ; carbonates: Th>295, 4.5-11.0 wt.% NaCl equ.). The Belo Brdo mine: Mineralisation is located on and close to the tectonic contacts of the Cretaceous carbonates with volcanoclastic rocks and/or serpentinite. The additional hydrothermal veins are located within Tertiary andesites. The preliminary FIs study was applied to quartz from hydrothermal replacement ore body (Th=135º C-350º C, with mode value at 230º C and two weaker maxima at 150º C and 320º C, 1.0-14.0 wt.% NaCl equ.). A mixing of magmatic with meteoric fluids is evident from the bivariate Th vs. salinity diagram. The Crnac mine: There are two type of mineralisations: vein type, hosted by Jurrassic amphibolites, and listwaenite mineralisation developed at the contact between amphibolites and overlying serpentinites. FIs study on quartz from listwaenite mineralisation reveal presence of high-temperature – low-salinity NaCl-H2O fluid (Th=249 - 324º C, 2.9 – 6.7 wt.% NaCl equ.), while fluids in the late stage carbonates are complex and bivariate. Primary fluid in the carbonate (CaCl2-NaCl± KCl-H2O, Th=247 - 325º C, 5.1 – 7.0 wt.% NaCl equ), is overprinted by the lower temperature CaCl2-NaCl-H2O-CO2 fluid (Th=219-268º C, 4.3 – 11.7 wt.% NaCl equ.), interpreted as an influance of meteoric water. Despite the variations between ore types and host-rock characteristics, major similarities are seen in fluid inclusion data, structural controls and sulfide mineralogy. It appears that the spectrum of mineralisation styles, shown by these deposits represent different responses to the same magmatic events.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA