Borojević Šoštarić 1, S., Cvetković 2, V., Neubauer 3, F., Palinkaš 4, LA., Bernroider 3, M., Genser 3, J.

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1 RUDARSKO- GEOLOŠKO NAFTNI FAKULTET FACULTY OF MINING, GEOLOGY AND PETROLEUM ENGINEERING Oligocene shoshonitic rocks of the Rogozna Mts. (Central Balkan Peninsula): evidence of petrogenetic links to the formation of Pb-Zn-Ag ore deposits Borojević Šoštarić 1, S., Cvetković 2, V., Neubauer 3, F., Palinkaš 4, LA., Bernroider 3, M., Genser 3, J. 1 Faculty of Mining, Geology and Petroleum Engineering, University of Zagreb, Pierottijeva 6, HR Zagreb, Croatia, sibila.borojevic-sostaric@rgn.hr; phone: ; fax: Faculty of Mining and Geology, University of Belgrade, SR Belgrade, Serbia 3 Department Geography and Geology, University of Salzburg, A-5020 Salzburg, Austria 4 Faculty of Science, University of Zagreb, Horvatovac 95, HR Zagreb, Croatia Rogozna Mts. panoramic view

2 Background and basic idea of the study Ore deposit study (Crnac mine, Rogozna Mts.) a link between volcanic rocks and Pb-Zn-Ag mineralization FI, IC, δ 13 C, δ 18 O, δ 34 S, Ore mineral chemistry, Geochemistry of volcanics, 40 Ar/ 39 Ar age dating Borojević Šoštarić, S., Palinkaš, A.L., Neubauer, F., Hurai, V., Cvetković, V., Roller-Lutz, Z., Mandić, M, Genser, J., Silver-base metal epithermal vein and listwaenite hosted deposit Crnac, Rogozna Mts., Kosovo, Part II: A link between magmatic rocks and epithermal mineralization. Ore Geology review (accepted). Borojević Šoštarić, S., Palinkaš, A.L., Topa, D., Spangenberg, J., Prochaska, W., Silver-base metal epithermal vein and listwaenite type of deposit Crnac, Rogozna Mts., Kosovo. Part I: Ore mineral geochemistry and sulfur isotope study. Ore Geology review 40, Oligocene quartz latite? is there an overall relationship between Oligocene quartz latite and Pb-Zn-Ag mineralization at the Rogozna Mts.? can we link it to specific shallow level magmatic process? can it be recognized/applyed throughout Vardar zone SCOPES Project - Conference and Field Trip - Štip, Macedonia

3 Study area Distribution of Upper Cretaceous and Cenozoic magmatic and metallogenetic belts of the Central Balkan Peninsula with the location of the study area (modified after Dimitrijević, 2002). Geological background 3

4 Study area Sample locations Geological sketch map of the Rogozna Mts. (modified after Urošević et al., 1966/73). Geological background 4

5 Rogozna fresh and hydrothermally altered quartz latite Hydrothermaly altered quartz latite Quartz latite Quartz latite Hydrothermaly altered quartz latite 5

6 Results - Rock classification, Petrography QAP diagram for classification of Rogozna Mts. rocks (Streckeisen, 1974). Pl, Bt, Amp, Qtz, Snd, Cpx Microphenocrysts: Phl, Tt BŠ et al., Lithos, accepted. 6

7 Results - Petrography Selected photomicrographs and BSE images of the Rogozna Mts. quartz latite a) amphibole phenocryst with narrow phlogopite overgrowths; b) phlogopite pseudomorph with a typical amphibole shape and irregular amphibole relicts in the central parts; c) phlogopite-rich microgranular aggregate containing a biotite crystal with clear phlogopite margins; note that outside the aggregate a phlogopite microphenocryst occurs with narrow biotite margins; d, e) compositional Fe and Mg EDS maps of the mica shown in c). BŠ et al., 2012 Lithos, accepted Crystallization P/T conditions Hbl-Pl T Amp core = 795 C C T Amp rim = 760 C C THomogenous Amp = 770 C C Ti in Bt T Bt = 720 C C Al in Hbl 7 P = kbar km

8 Diagrams showing chemical composition of amphibole; a) Si vs Na B, and b) Si vs. (Mg/Mg+Fe 2+ ; after Leake et al., 1997). Results Mineral chemistry TiO 2 vs Al 2 O 3 (wt %) diagram for phlogopite, phlogopitized biotite and biotite from the Rogozna Mts. quartz latite. Data fields for phlogopite and phlogopitized biotite from lamproites from Rudnik and Zabrdica (Prelević et al., 2004) and calcalkaline lamprophyres and ultrapotassic rocks from the Roman Province from Mitchell and Bergman (1991). 8 BŠ et al., 2012 Lithos, accepted

9 Results - Geochemistry a) Primitive mantle-normalized multi-variation diagram according to Sun and McDonough (1989), and b) chondrite-normalized REE pattern of the Rogozna quartz latite rocks according to Boynton (1984). The pattern of ultrapotassic Serbian Cenozoic rocks (Prelević et al., 2005) is given for comparison. 9

10 Results 40 Ar/ 39 Ar age dating 27.3± ±0.1 Ma BŠ et al 2011, Crnac mine Alterations 28.6±0.5 Quartz latite 28.9±0.3 Ma Sketch of the 40 Ar/ 39 Ar ages of the quartz latites from Rogozna Mts. and Mt. Zvečan and associated alterations. 10

11 Discussion a) SiO 2 wt% vs K 2 O wt%, and b) SiO 2 wt% vs Na 2 O/K 2 O plots for the Rogozna Mts. quartz latite. Volcanic and plutonic rocks of several other Cenozoic provinces of Serbia are also plotted (Lece: Malešević et al., 1980; Borač: Cvetković et al., 2001; Surdulica: Vasković and Jović, 1993; Kopaonik volcanic rocks: Mićić, 1980; Kopaonik granitoids: Mićić, 1980, Zelić et al., 2010; Veliki Majdan: Prelević et al., 2004, Beli Kamen: Prelević et al., 2001; Rudnik: Cvetković, unpublished). Fields on SiO 2 wt% vs K 2 O wt% according to Peccerillo and Taylor (1976). HK subgroup disequilibrium features evidence of magma mixing CA subgroup 11 CA HK

12 Discussion a) Zr vs Th/Zr; b) Zr vs Nb/Zr; c) K 2 O vs Al 2 O 3 /Zr, and d) SiO 2 vs Al 2 O 3 /Zr plots for Rogozna Mts. quartz latite and rocks of other Serbian Cenozoic igneous provinces. A solid line represents a binary mixing between a lamproite magma (sample RO/1-II, Prelević et al., 2001) and a dacite-like calc-alkaline melt (calculated as the average composition of 57 Oligocene granodiorite and monzogranite samples from the area of Surdulica; Vasković and Jović, 1993). CA Magma mixing processes HK HK CA CA HK CA CA HK HK 12

13 Conclusions Model for the formation of the Rogozna Mts. quartz latite complex. 13 BŠ et al., 2012 Lithos, accepted

14 Thank you for your attention. 14