PT-FORMATION CONDITIONS OF POLYMETALLIC ORES FROM THE Pb-Zn-Fe AKTASH SKARN DEPOSIT (WESTERN KARAMAZAR, TAJIKISTAN)

Abstract

Fluid inclusions are studied in calcite from magnetite ores and sulfide-carbonate veins of the Aktash sulfide-magnetite deposit (Western Karanazar, Tajikistan) to identify their formation conditions. The deposit is confined to a contact zone between carbonate (Upper Devonian–Lower Carboniferous dolomite and limestones) and intrusive rocks (Middle Carboniferous–Early Triassic granodiorites and porphyry granodiorites) of the Kansai ore field. The fluid inclusion study showed that calcite of ore veins formed from moderately saline (4.4–10.8 wt. % NaCl-equiv.) aqueous Na-K ± Mg chloride fluids at a decreasing temperature from 300 to 160 °C. The homogenization temperatures of fluid inclusions are consistent with thermometric data for chlorite, which formed together with calcite (176–295 °C).

Keywords

• calcite
• chlorite
• formation conditions
• fluid inclusions
• polymetallic ores
• magnetite ores
• aktash deposit
• western karamazar