Geochemistry of Hydrothermal Alteration Associated with Cenozoic Intrusion-Hosted Cu-Pb-Zn Mineralization at Tavşanlı Area, Kütahya, NW Turkey

Abstract

Abstract:The Miocene magmatic intrusion in the Tavşanlı zone of the Kütahya-Bolkardag Belt (KBB) in the northwestern region of Turkey is represented by the Egrigöz granitoids. This paper studies the petrology and geochemistry of hydrothermal alterations associated with the vein-type Cu-Pb-Zn mineralization hosted by this pluton, focusing on the determination of the mass gains and losses of chemical components, which reflect the chemical exchanges between the host rocks and hydrothermal fluids. Vein-type Cu-Pb-Zn mineralization is closely associated with intense hydrothermal alterations within the brecciation, quartz stockwork veining, and brittle fracture zones that are controlled by NW-SE trending faults cutting through the Egrigöz granitoids. Paragenetic relationships reveal three stages of mineralization: pre-ore, ore, and supergene. The ore mineralogy typically includes hypogene chalcopyrite, sphalerite, galena, and pyrite, with locally supergene covellite, malachite, and azurite. Wall-rock hypogene hydrothermal alterations include pervasive silicification, sulfidation, sericitization, and selective carbonatization and albitization. These are distributed in three main alteration zones (zone 1: silicified/iron carbonatized alterations˘albite, zone 2: argillic-silicic alterations, and zone 3: phyllic alterations). Based on the gains and losses of mass and volume (calculated by the GEOISO-Windows™ program), zone 1 has a higher mass and volume gain than zones 2 and 3. Non-systematic zonal distributions of alterations are observed in which the silicic-carbonate alterations +/´albitization appeared in zone 1 in the center and the phyllic-argillic alterations appeared in zones 2 and 3, with an increase in base metals (Cu-Pb-Zn) in the zone from Cu, Cu-Pb, to Cu-Pb-Zn moving outwards.

Direct observation and measurement of Au and Ag in epithermal mineralizing fluids

“…In the Biga Peninsula (Okay et al 1990;Yilmaz et al 1990;Ercan et al 1995;Sanchez et al 2013;Bertrand et al 2014) this has resulted in numerous, predominantly, epithermal deposits, of low, intermediate and high sulphidation styles and porphyry deposits, making this region, perhaps, the most important for exploitation and exploration in the near east/Europe (Yigit, 2012). The deposits are relatively closely spaced, of variable size and may have gold as the sole resource, while others are base-metal resources with lesser or sub-economic amounts of gold (Bozkaya, 2001;Yilmaz, 2002;Oyman et al 2003;Orgun et al 2005;Bozkaya and Gokce, 2009;Yilmaz et al 2010;Ozen and Arik, 2013;2015;Imer et al 2013;Bozkaya et al 2014;Smith et al 2014;Kumral et al 2016).…”

Genesis and Evolution of the Yolindi Cu-Fe Skarn Deposit in the Biga Peninsula (NW Turkey): Insights from Genetic Relationships with Calc-Alkaline Magmatic Activity

“…In skarn deposits, mass balance calculations assist to quantify elemental gains, losses, and redistributions during the transformation from unaltered rock to skarn. Depending on the fluid composition, temperature, pH, Eh, and host-rock compositions, the chemical ion exchange between host/wall rocks and hydrothermal fluid results in the formation of new altered minerals and alteration zones [32,92,93]. The gain and loss of rock mass components is common during hydrothermal alteration processes [94].…”

“…The EPMA data show that the cerussite has a higher PbCO 3 amount with a range of 98.85 and 99.97 and low amounts of CaCO 3 , FeCO 3 , and SrCO 3 , with an average of 0.27, 0.17, and 0.02 (Table 11). ion exchange between host/wall rocks and hydrothermal fluid results in the formation of new altered minerals and alteration zones [32,92,93]. The gain and loss of rock mass components is common during hydrothermal alteration processes [94].…”

Petrology and Geochemical Relationship of Birimian Gabbro-Diorite-Granodiorite Dykes in Basaltic Rocks at Butre Area, SW Ghana

“…At Galore Creek of Canada, diorite/monzonite intruded into sandstone, siltstone and chert and introduced hydrothermal potassic-calcic alterations (Micko et al, 2014). In the Tavsanlı area in Turkey, the Egrigöz granitoids intrusion into various gneisses and schists caused silicification, argillic-sillicic, and phyllic alterations along fault/shear zones at the contacts of granitoids (Kumral et al, 2016). In India, Rajastan, metavolcanic rocks intruded by granitoids have undergone mineralogical changes: oligoclase to albite, and biotite to annite, while rocks unaffected by hydrothermal activities remain intact (Kaur et al, 2012).…”