Mineralogy, Geochemistry, Fluid Inclusion and Oxygen Isotope Investigations of Epithermal Cu ± Ag Veins of the Khur Area, Lut Block, Eastern Iran

The Khur metallogenic district is located in a volcanic-plutonic belt in the central Lut Block(central eastern Iran). Mineralization occurs in Middle Eocene andesitic tuff and along four main vein systems trending northwest-southeast(Shurk, Mir-e-Khash, Shikasteh Sabz and Ghar-e-Kaftar veins).Microscopic studies reveal that the veins contain bornite, chalcocite, pyrite, tennantite together with minor sphalerite and chalcopyrite as hypogene minerals and chalcocite, digenite, covellite, valleriite,malachite, azurite, atacamite, hematite, and goethite as supergene minerals. The ore bodies are accompanied by narrow but intensely developed wall rock alterations of argillization, carbonatization and silicification. Copper content reaches 6.5, 2.4, 4.2 and 5% in Mir-e-Khash, Shikasteh Sabz, Ghar-eKaftar and Shurk, respectively. Microthermometric measurements of quartz-and calcite-hosted fluid inclusions indicate that the mineralization might be derived from a moderately saline hydrothermal fluid at temperatures between 175-316℃. Calculated δ~(18)O values of water in equilibrium with quartz and calcite for Khur veins suggest that the fluid might have had a magmatic source, but the ~(18)O-depletion was developed through mixing with meteoric water. Copper deposition in Khur veins is believed to have been largely caused by mixing, although wall rock reactions may also have occurred. The Khur veins are classified as volcanic-subvolcanic hydrothermal-related vein deposits.

Mineralogy,Geochemistry, Fluid Inclusion and Oxygen Isotope Investigations of Epithermal Cu ± Ag Veins of the Khur Area,Lut Block,Eastern Iran

The Khur metallogenic district is located in a volcanic–plutonic belt in the central Lut Block (central eastern Iran). Mineralization occurs in Middle Eocene andesitic tuff and along four main vein systems trending northwest–southeast (Shurk, Mir‐e‐Khash, Shikasteh Sabz and Ghar‐e‐Kaftar veins). Microscopic studies reveal that the veins contain bornite, chalcocite, pyrite, tennantite together with minor sphalerite and chalcopyrite as hypogene minerals and chalcocite, digenite, covellite, valleriite, malachite, azurite, atacamite, hematite, and goethite as supergene minerals. The ore bodies are accompanied by narrow but intensely developed wall rock alterations of argillization, carbonatization and silicification. Copper content reaches 6.5, 2.4, 4.2 and 5% in Mir‐e‐Khash, Shikasteh Sabz, Ghar‐e‐Kaftar and Shurk, respectively. Microthermometric measurements of quartz‐ and calcite‐hosted fluid inclusions indicate that the mineralization might be derived from a moderately saline hydrothermal fluid at temperatures between 175–316°C. Calculated δ¹⁸O values of water in equilibrium with quartz and calcite for Khur veins suggest that the fluid might have had a magmatic source, but the ¹⁸O‐depletion was developed through mixing with meteoric water. Copper deposition in Khur veins is believed to have been largely caused by mixing, although wall rock reactions may also have occurred. The Khur veins are classified as volcanic‐subvolcanic hydrothermal‐related vein deposits.