109 / 1971-01-01 00:00:00

Volconogenic Massive Sulfide Mineraliztion In The Kashan-delijan Region, Iran

Volconogenic massive sulfide (VMS) mineralization in the Kashan-Delijan region occurred in the Urumieh-Dokhtar magmatic arc, as several deposits and occurrences such as the Varandan Ba-Pb-Cu, Dareh-Amrood Pb-Zn, and Tapeh-Sorkh and Dorreh Ba deposits. The host bimodal Middle-Late Eocene volcano-sedimentary sequence is composed of gray and green siliceous tuff, breccia tuff, andesitic-basalt lava, rhyolite, shale, limestone, marl and pyroclastic rocks. Major host rocks of the mineralization are volcaniclastics and tuffacious rocks. The orebodies are lenticular to tabular, with variable thickness. Ore minerals are mainly barite, galena, sphalerite, chalcopyrite, pyrite, bornite, tetrahedrite, magnetite and hematite, accompaning with secondary minerals such as native copper, cuprite, covellite, chalcosite, goethite, hematite and malachite. Gangue minerals consist of chlorite, sericite, quartz and calcite. Major wall rock alterations in the deposits are chloritic and quartz-sericitic. The VMS mineralization in the region are of Kuroko-type deposits, formed in an intra-arc setting due to subduction of the Neo-Tethyan ocean crust beneath the Iranian plate.