Low-sulfidation epithermal Au-Ag mineralization in the Sındırgı District, Balıkesir Province, Turkey

Authors : Hüseyin YILMAZ, Fatma Nuran SÖNMEZ, Erhan AKAY, Ahmet Kerim ŞENER, Seda TEZEL TUFAN

Pages : 485-522

Doi:10.3906/tar-1206-8

View : 18 | Download : 6

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The Sındırgı District insert ignore into journalissuearticles values(Balıkesir, western Turkey); lies within the Western Anatolian volcanic and extensional province, adjacent to the WNW-trending Simav graben, approximately 130 km NE of İzmir. The Sındırgı mining district is underlain mainly by Miocene volcanic rocks and hosts several low-sulfidation epithermal Au-Ag deposits and prospects located near the towns of Sındırgı and Bigadiç. The Kızıltepe low-sulfidation epithermal gold-silver deposit is located southeast of Yusufçam village insert ignore into journalissuearticles values(Sındırgı, Balıkesir);, and other prospects, including the Kepez, Kavaklıdüz, and Karadüz prospects, are located northeast of Kızıltepe. Potentially economic grades occur at Kızıltepe, which contains a measured and indicated resource of 1.754.790 Mt @3.0 g/t Au, 44 g/t Ag, hosted by quartz veins showing colloform/crustiform banding, quartz pseudomorphs after bladed calcite, and multiphase brecciations, all typical textures noted in low-sulfidation epithermal deposits. Alteration minerals include mixed-layer illite/smectite, high-crystallinity illite, and kandite group minerals insert ignore into journalissuearticles values(dickite and nacrite);. Precious metal minerals include traces of electrum, acanthite, Au-rich acanthite, and Ag-Hg-Au-Tl-Pb series, occurring mainly within quartz. Pyrite is the most common opaque mineral at Kızıltepe. 40Ar/39Ar dating of adularia from the quartz veins indicates an age of mineralization of 18.3 ± 0.2 Ma. The ore mineralization is divided into three main phases. These comprise the deposition of: coarse-grained quartz, illite, pyrite, and minor precious metals insert ignore into journalissuearticles values(Phase I);; major gold–silver-bearing medium-grained quartz, which commonly exhibits crustiform banding, carbonate replacement, and hydrothermal breccia textures insert ignore into journalissuearticles values(Phase II);; and fine-grained chalcedonic quartz with colloform/crustiform banding insert ignore into journalissuearticles values(Phase III);. Phase II is economically the most important in terms of precious metal content. Phase II quartz contains fluid inclusions, which range from predominantly vapor-rich to predominantly liquid-rich with homogenization temperatures insert ignore into journalissuearticles values(Th); varying from 157 to 330 °C, showing a cluster between 190 and 300 °C, and ice-melting temperatures insert ignore into journalissuearticles values(Tm); ranging from -0.2 to -2.9 °C insert ignore into journalissuearticles values(salinity from 0.5-4.8 wt.% NaCl equiv.);. Moderate to strong positive correlations occur between Au-Ag insert ignore into journalissuearticles values(R = 0.8); and Au-Cu insert ignore into journalissuearticles values(R = 0.5);, whereas there is no correlation between As and Au or Ag.
Keywords : Key words Gold, hydrothermal alteration, geochronology, fluid inclusions, Sındırgı