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3070136 
Journal Article 
The Agios Georgios argentiferous galena deposit on Antiparos Island, Cyclades, Hellas and its relationship to the Paros leucogranite 
Kevrekidis, E; Seymour, KSt; Tombros, S; Zhai, D; Liu, J; Zouzias, D 
2015 
1 
Neues Jahrbuch fuer Mineralogie. Abhandlungen
ISSN: 0077-7757 
192 
3 
239-261 
WOS:000358897500002 
The Agios Georgios argentiferous galena deposit on Antiparos island lies similar to 12 km from the Miocene Paros pluton and is hosted by mineralized quartz veins in marbles of the Cycladic Blueschist Unit. Argentiferous galena and clear quartz were deposited in the epithermal stage in veins armoured by higher temperature milky quartz. The Paros pluton is a mesozonal volatile-rich tourmaline and Li-bearing muscovite leucogranite emplaced at ca. 700 degrees C and 4-5 kbars. Fluid inclusion microthermometry of vein quartz yielded ore fluid temperatures from 130 degrees to 400 degrees C, salinities from 4.8 to 15.7 NaCl wt. percent equivalent and pressures of 100 to 135 bars. CO2-effervescence of the ore fluid at the high end of the temperature range is suggested by Raman data along with CO2 clathrate formation. Closure and boiling and reopening of the mineralized quartz veins occurred between 240 to 290 degrees C. Raman spectroscopy of fluid inclusions showed significant contents of Cu2+ and SO42- indicative of the mineralization and of Li+ and B3+ indicative of magmatic fluid contribution. Raman ratios, i.e., logX(O2)/X-H2O indicate mixing with meteoric water. Stable isotope analyses of vein quartz yielded delta O-18(H2O) and delta D-H2O values of the hydrothermal fluid from 1.2 to 11.6 and -73.2 to -52.4 per mil, respectively and delta Si-30 from -0.6 to 0.0 per mil. All are consistent with a dominant magmatic origin of ore fluids. The physicochemical conditions of the ore deposition were pH =3.6-5.5, logfS(2) = -9.7 to -7.3 and logfO(2) = -31.3 to -34 for 330 degrees and 210 degrees C and pressures of 135 bars. The volatile-rich nature of the Paros pluton, the presence of granitophile elements such as Li+ and B3(+) in fluid inclusions in the vein quartz, the high salinities of the fluid inclusions, the initial high T (>400 degrees C) of the mineralizing event and the magmatic signature of stable isotopes in mineralized vein quartz suggest that mineralizing fluids were derived from the leucogranite. 
Paros leucogranite; Antiparos epithermal mineralization; fluid inclusions; Raman; stable isotopes